RICAP-22 Roma International Conference on AstroParticle Physics

6 Sept 2022, 14:00 → 9 Sept 2022, 16:30 Europe/Rome

Aula Amaldi (Physics Department, University "La Sapienza", Roma, Italy)

Antonio Capone

As you know, the 8th edition of the Roma International Astroparticle Physics conference, planned during 2020 for June 30-July 3rd in Roma “La Sapienza University”, has been cancelled due to Covid-19 pandemic.  
The Local Organizing Committee went quite far with the organization of the event: following the indications of the IAB several colleagues have been invited to contribute to the Conference, several colleagues have agreed to collaborate as conveners for the parallel sessions, many positive answers have been already received. 
We plan to organise the 8th edition of the Conference in the period September 6th-9th 2022.
We hope for that time the overall world health conditions will allow to travel and to meet for a Conference "in presence"

 

The CRISS 2022 Conference in Napoli 12-16 September is just after Ricap. 
Take the opportunity to come to both conferences !

 

 

 

Previous editions:

RICAP – 2007, May 22nd–24th, INFN and University "La Sapienza", Roma

RICAP – 2009, May 20th–22nd, INFN and University "Tor Vergata", Roma

RICAP – 2011, May 25th 27th, INFN and University "Roma Tre", Roma

RICAP – 2013, May 22nd–24th, INFN and University La Sapienza, Roma

RICAP - 2014,  September 30th-October 3rd, INFN-LNS, Noto

RICAP - 2016,  September 5th-8th, Villa Tuscolana, Frascati, Roma

RICAP – 2018, September 4th-7th, INFN and University "Roma Tre", Roma

 

Bulletin_n2_RICAP_2022.pdf

First_Bulletin_RICAP_2022.pdf

web-conf.zip

Tuesday, 6 September

14:00 → 19:00 Registration

Wednesday, 7 September

08:45 → 10:25 I Plenary Session chair Antonio Capone

08:45 Introduction and welcome greetings.

09:00 Multimessenger signals from Pevatrons

The origin of Cosmic Rays (CR), more than 100 years after their discovery, remains a "century-old mystery". Therefore the identification of the astronomical sources responsible for the locally measured fluxes of CRs remains one of the highest priorities of the field. Although the discovery of TeV gamma-radiation from SNRs generally supports the SNR paradigm of Galactic CRs, the lack of the extension of gamma-ray spectra of young SNRs well beyond 10 TeV raises doubts about their ability to contribute to the highest energy galactic CRs in the so-called "knee" region around 1 PeV. Meanwhile, the ultra-high-energy (UHE; E> 100 TeV) gamma-ray observations of young clusters of massive stars demonstrate mounting evidence of these objects being prime contributors to Galactic CRs at PeV energies. I will highlight the implications of these observations in the context of "Young Stars versus Dead Stars" and discuss the perspectives linked to the studies of PeVatrons in UHE neutrinos, gamma-rays and the synchrotron emission of secondary electrons produced in hadronic interactions.

Speaker: Felix Aharonian (Dublin Institute for Advanced Studies)

RICAP-Sep6.pdf

09:30 On the hadronic origin of the TeV radiation from GRBs and the expected neutrino flux.

The recently discovered TeV emission from Gamma-Ray Bursts (GRBs) hints towards a possible hadronic origin of this radiation component. To investigate such scenario, we developed a tailored Monte Carlo (MC) simulation that reproduces the kinematics of photo-hadronic interactions occurring at internal shocks, including the electromagnetic cascade process that the resulting secondary gamma rays undergo inside the GRB jet. As a result, we find that sub-TeV observations of GRB190114C can be reproduced by a baryonic energy content comparable to that in sub-GeV photons and a bulk Lorentz factor Gamma ~100. Neutrino flux predictions are found to be consistent with experimental upper limits set by ANTARES and IceCube.

Speaker: Prof. Dafne Guetta (Physics Department, Ariel University,)

Guetta_slides.pdf

10:00 VHE Sky Monitoring with the Southern Wide-field Gamma-ray Observatory

The Southern Wide-field Gamma-ray Observatory (SWGO) is the proposal for a new ground-based gamma-ray instrument in the Southern Hemisphere, which will use an array of water-Cherenkov based particle detectors to provide continuous monitoring and regular scanning of a large portion of the sky at the very- and ultra-high-energies (VHE and UHE, respectively). At the low energy side, SWGO aims to push the observational range of wide-field ground-based gamma-ray facilities down to a few hundred GeV, thus bridging the gap between space and ground-based facilities in the monitoring of the VHE sky. In so doing, SWGO could become a unique instrument in the search for short time-scale transient phenomena, being an important addition to the global network of multi-messenger astrophysics. In the high energy domain, on the contrary, it will benefit from the optimal coverage of the Galactic Plane to map the distribution of UHE sources in the inner parts of the Galactic disk and close to the Galactic Center, leading to an extraordinary improvement of our ability to identify their most likely counterparts. In this contribution, we will describe the potential of SWGO to constrain the physics of VHE emission and particle acceleration in gamma-ray sources powered by relativistic jets and energetic shocks. We will discuss its role in our understanding of the origin of the spectrum of high energy particles and its contribution to the global network of multi-messenger facilities.

Speaker: Giovanni La Mura (Laboratório de Instrumentação e Física Experimental de Partículas)

LaMura_Science_with_SWGO.pdf

10:25 → 10:55 Coffee Break

10:55 → 13:06 II Plenary Session chair Aldo Morselli

10:55 The MAGIC project status and results

MAGIC is a system of two 17-m diameter Imaging Atmospheric Cherenkov Telescopes, located at an altitude of 2200 m in the Observatorio Roque de los Muchachos on the Canary island of La Palma. MAGIC provides a broad energy coverage, detecting gamma rays from 50 GeV and up to 100 TeV.
A careful strategy of alert follow-ups from other facilities and the fast reposition of the telescopes as well as multi-wavelength campaigns are instrumental for the MAGIC observation program. In this contribution I will present a selection of the latest scientific results obtained by the MAGIC telescopes, such as the detections of gamma-ray burst at very high energies, the evidence for proton acceleration in the nova RS Ophiuchi, and the importance of MAGIC observation during multimessenger and multiwavelenght campaigns on the extragalactic sky.

Speaker: Chiara Righi (INAF - OABrera)

20220906_v2.pdf

11:20 Recent H.E.S.S. highlights and status

The High Energy Stereoscopic System (H.E.S.S.) is an hybrid array of five imaging atmospheric Cherenkov telescopes located in the Khomas Highlands of Namibia to study gamma-ray emission in the energy range from several ten GeV up to several ten TeV. Started 20 years ago, stereoscopic observations provide an unprecedented view of a variety of astrophysical objects, from pulsars and supernova remnants in the Milky Way to active galactic nuclei and gamma-ray bursts at cosmological distances. Located in the Southern hemisphere, H.E.S.S. allows for exclusive observations of the Milky Way and the Galactic centre region. The array has been upgraded with new cameras. Hardware upgrades and changes in the operational procedures increased the amount of observing time, which is of key importance for time-domain science. I will present the status of the H.E.S.S. experiment and discuss its latest highlights including observations of Galactic novae, pulsars, supernovae, inner Galactic halo, gravitational wave follow-ups, and searches for Pevatrons and dark matter.

Speaker: Emmanuel Moulin (CEA Saclay)

Emmanuel_RICAP2022.pdf

11:45 Status and results of LST-1

The Large-Sized Telescopes (LSTs) will be one of three telescope types composing the Cherenkov Telescope Array (CTA). LSTs will dominate the CTA performance at the lowest gamma-ray energies, especially between 20 GeV and ∼150 GeV, thanks to the tessellated parabolic mirror of 23 m diameter and the ultrafast imagining camera with 4.5 degrees field of view consisting of 1855 high efficiency photomultiplier tubes.
The CTA North site in La Palma, Canary Islands, Spain will host the sub-array of four LSTs. The commissioning of the first LST, LST-1, which was inaugurated in October 2018, is ongoing.
During its commissioning period, LST-1 has observed various astrophysical sources in monoscopic mode, producing very promising early scientific results, like the detection at VHE of the nova RS Ophiuci and a flare of BL-Lac (announced in July 2021 with the first LST-1 ATel).
The presentation will focus on the status of LST-1 commissioning, the preliminary scientific results and the future prospects.

Speaker: Alice Donini (INAF - OAR)

Ricap22_ADonini_v3.pdf

12:10 The Cherenkov Telescope Array Observatory

The field of very high energy (VHE; >100GeV) gamma-ray astronomy is set to enter a new epoch with the arrival of the Cherenkov Telescope Array Observatory (CTAO). Since the birth of the field in 1989, with the discovery of emission above 1 TeV from the Crab nebula, almost 200 sources have been identified by the previous and current generations of experiments. The study of these sources has provided exciting glimpses into the physics of the most extreme known environments. To further our understanding of the very high energy gamma-ray sky, a significant enhancement in sensitivity at TeV energies is required. A wider energy coverage from tens of GeV to hundreds of TeV and improved angular and energy resolution, with respect to the currently running facilities, are also essential. The major topics that CTAO will address cover the broad themes: the role and origin of cosmic rays, studying extreme environments and probing the frontiers of physics. As an open proposal-driven observatory, with access to the full sky, new breakthroughs will be made possible by allowing the entire astronomical community to explore data in a new discovery space. Additionally, CTAO will achieve an unprecedented sensitivity to short-timescale phenomena, making it a key instrument for the future multi-messenger and multi-wavelength time domain astronomy including collaborations with gravitational wave and neutrino observatories.

Speaker: Gareth Hughes

CTAO_Hughes.pdf

12:35 Gravitational Wave and Black Holes

The detection of Gravitational Waves emitted during the merging phase of compact binary objects to stellar-mass Black Holes by the LIGO-Virgo-KAGRA collaboration constitute major achieve-ments of Modern Science. These discoveries require further investigations to answer critical questions about the population density and the formation process of the binary system. These investigations also hold the potential of paving the way for the detection of quantum-mechanical effect somehow related to the black hole thermodynamics. In this paper we will review, in a short, few preliminary results on this domain and the future perspectives of the LIGO-Virgo-KAGRA measurements.

Speaker: Fulvio Ricci (Istituto Nazionale di Fisica Nucleare)

RICAP-2022_n.pdf

13:05 atm position

Speaker: Antonio Capone (Istituto Nazionale di Fisica Nucleare)

mappa-ATM.pdf

13:06 → 14:00 Lunch break

14:00 → 16:20 Cosmic Rays - 1

Conveners: Paolo Desiati (University of Wisconsin - Madison), Philipp Mertsch (TTK, RWTH Aachen University)

14:00 Study of cosmic-ray solar modulation with the PAMELA experiment

The data collected by the satellite-borne PAMELA experiment, launched in June 2006, opened a new era of high-precision studies of cosmic rays. The PAMELA low detection energy threashold and long operativity enabled accurate measurements of the fluxes of several cosmic-ray species over a large energy range and the study of their time variation below a few tens of GeVs. In particular, these measurements covered a time that included the minimum phase of the 23rd solar cycle and the 24th solar maximum including the polarity reversal of the solar magnetic field. These measurements have allowed to significantly improve the understanding of the charged-particle propagation through the Heliosphere, the charge-sign effect due to the drift motions of these particles and to calibrate state-of-the-art models of cosmic-ray transport in the Heliosphere. In this presentation we will review PAMELA results on the time-dependent proton, helium and electron fluxes measured between a few tens of MeV/n and few tens of GeV/n from 2006 to 2014. Moreover, preliminary results of yearly energy spectra of deuterons, helium-3 and helium-4 nuclei below 1 GeV/n will be discussed.

Speaker: Alex Lenni (Istituto Nazionale di Fisica Nucleare)

RICAP 2022 Lenni.pdf

14:20 Modeling solar modulation of cosmic rays in light of new data from AMS-02 and PAMELA

When traveling inside the heliosphere, cosmic rays are influenced by magnetic turbulence and solar wind disturbances, which result in the so-called solar modulation effect. Understanding solar modulation is essential for studying the origin and the propagation processes of Galactic cosmic rays, as well as for establishing of predictive models of energetic radiation in space. In this talk, we present our efforts in the development of a comprensive model for the time- and energy-dependent solar modulation effect. In particular, we present our numerical description of the structure of the heliosphere, our simulations for the transport of charged particles and antiparticles in the interplanetary space. We discuss the role of the most recent data from space experiments such as AMS-02 or PAMELA in constraining the model parameters and revealing new important details of the solar modulation phenomenon.

Speaker: Nicola Tomassetti (University of Perugia & INFN, Italy)

NT_07Sep2022_RICAP_CRMod.pdf

14:40 Precision Measurement of the Monthly Proton, Helium, Carbon and Oxygen Fluxes in Cosmic Rays with the Alpha Magnetic Spectrometer on the International Space Station

Cosmic Rays (CR) inside the Heliosphere interact with the solar wind and with the interplanetary magnetic field, resulting in a temporal variation of the cosmic ray intensity near Earth for rigidities up to few tens of GV. This variation is known as Solar Modulation. Previous AMS results on proton and helium spectra showed how the two fluxes behave differently in time. To better understand these unexpected results, one could therefore study to the next most abundant species. In this contribution, the precision measurements of the monthly proton, helium, carbon and oxygen fluxes for the period from May 2011 to Nov 2019 with the Alpha Magnetic Spectrometer on the International Space Station are presented. The detailed temporal variations of the fluxes are shown up to rigidities of 60 GV. The time dependence of the C/O, He/(C+O), p/(C+O), and p/He are also presented and their implication on the shape of the nuclei LIS is discussed.

Speakers: Dr Alejandro Reina Conde (INFN Bologna), Dr Federico Donnini (Istituto Nazionale di Fisica Nucleare)

RICAP2022_alejandro_reina_conde.pdf

15:00 Electron and positron fluxes in primary cosmic rays measured with the AMS-02 detector on the ISS

The Alpha Magnetic Spectrometer, AMS-02, is a magnetic spectrometer detector operating on the International Space Station (ISS) since May the 19th, 2011. The latest precision results on cosmic-ray electrons up to 1.4 TeV and positrons up to 1 TeV are providing new insights into the origin of high energy cosmic-ray electrons and positrons. In the entire energy range the electron and positron spectra have distinctly different magnitudes and energy dependences. The analysis of the time dependences of low energy electron and positron fluxes exhibits common short-term features and different long-term behaviour, proving evidence of charge-dependent effects in solar modulation of low energy cosmic-ray fluxes. In this contribution we describe the latest AMS-02 experimental results on the measurements of GeV and TeV cosmic-ray electrons and positrons .

Speaker: Matteo Duranti (Istituto Nazionale di Fisica Nucleare)

Duranti-Electrons_and_Positrons_AMS_light.pdf

15:20 The High-Energy Particle Detector (HEPD-01): observations and results after 4 years in orbit

The High-Energy Particle Detector (HEPD-01) onboard the China Seismo-Electromagnetic Satellite (CSES-01) - launched in February 2018 - is a light and compact payload suitable for measuring electrons (3-100 MeV), protons (30-300 MeV), and light nuclei (up to a few hundreds of MeV) with a high energy resolution and a wide angular acceptance. The very good capabilities in particle detection and separation, together with the Sun-synchronous orbit, make HEPD-01 well suited for the observation of the wide plethora of particle populations in Low-Earth Orbit. During its first 4 years of data-taking, the detector – completely designed and built in Italy – gathered results on galactic, solar and trapped particles with energies between tens and hundreds of MeVs, contributing to better understanding some aspects of particle transport inside the heliosphere, the mechanism of acceleration during Solar Particle Events and to obtain very good insights of particle behavior during various geomagnetic storms. The mission will continue taking data throughout the current solar cycle, serving as a very reliable and accurate tool for studying low-energy particles in near-Earth space.
In this contribution, we report some of the results obtained by HEPD-01, together with some information on the data-analysis techniques employed for this kind of studies.

Speaker: Matteo Martucci (Istituto Nazionale di Fisica Nucleare)

Martucci_RICAP22_CSES_20220907.pdf

15:40 Inference of the Local Interstellar Spectra of Cosmic-Ray Nuclei Z ≤ 28 with the GALPROP–HELMOD Framework: Prediction Capability and Hints of Excesses

Since its launch, the Alpha Magnetic Spectrometer-02 (AMS-02) has delivered outstanding quality measurements of the spectra of cosmic-ray (CR) species (p¯, e±) and nuclei (H–Si, Fe), which resulted in a number of breakthroughs. Spectra of heavier low-abundance nuclei are not expected until later in the mission. Consequently, we exploited a “fraction” of HEAO-3-C2 data that match available AMS-02 measurements, together with Voyager 1 and ACE-CRIS data, to make predictions for the local interstellar spectra (LIS) of nuclei that are not yet released by AMS-02. The resulting H to Ni LIS, in the energy range from 1 MeV/n to 100÷500 TeV/n, cover 8÷9 orders of magnitude in energy. In this context, some peculiar excesses have been found, hinting at possible primary components. The observed excesses in Li, F, and Al appear to be consistent with the local Wolf-Rayet stars hypothesis, invoked to reproduce anomalous 22Ne/20Ne, 12C/16O, and 58Fe/56Fe ratios in CRs, while excess in primary Fe is likely connected with a past supernovae activity in the solar neighborhood.

Speaker: Nicolò Masi (Istituto Nazionale di Fisica Nucleare)

RICAP2022_Masi.pdf

RICAP2022_Masi.pptx

16:00 Self-confinement of low-energy cosmic rays around supernova remnants

Supernova Remnants have long been considered as promising candidate sources for cosmic rays. However, modelling the transport around these sources is difficult due to its nonlinear nature. The strong overdensity in the near source region leads to the production of plasma turbulence, upon which the particles scatter. To calculate this mechanism, called self-confinement, requires the numerical solution of two coupled differential equations describing the transport of particles and waves, most often done in the flux tube approximation. Here, this formalism is extended to energies below $10\,\mathrm{GeV}$, where energy losses become relevant. Particles around $100\,\mathrm{MeV}$ are found to be confined for in between $300\,\mathrm{kyr}$ and $1\,\mathrm{Myr}$, depending on the interstellar medium. The diffusion coefficient is initially suppressed by up to two orders of magnitude. Interestingly, the spectrum outside the supernova flattens below $1\,\mathrm{GeV}$ at later times, similar to the spectral behavior observed by Voyager. Furthermore, the grammage accumulated in the near source region is found to be non-negligible, which could be important for precision fitting cosmic ray spectra.

Speaker: Hanno Jacobs

RICAP_talk_Hanno_Jacobs.pdf

14:00 → 16:20 Direct DM searches: - 1

Conveners: Elisabetta Baracchini (Istituto Nazionale di Fisica Nucleare), Ranny Budnik (Weizmann Institute of Science)

14:00 The XENONnT experiment

XENONnT is the follow-up to the XENON1T experiment aming for the direct detection of dark matter using a liquid xenon (LXe) time projection chamber (TPC). The detector, operated at Laboratori Nazionali del Gran Sasso (LNGS) in Italy, features a total LXe mass of 8.5 tonnes of which about 6 tonnes are active. XENONnT has completed its first science run and is currently taking data for the second science run. XENONnT has achieved unprecedented purity for both electronegative contaminants, with an electron lifetime exceeding 10 ms due to a novel purification in liquid phase, and for radioactive radon, with an activity of 1.72±0.03 𝜇Bq/kg due to a novel radon distillation column.
This talk will give an overview of the XENONnT experiment, results from the commissioning of the detector and its new subsystems, as well as the status of the analysis of the first science run and its projections.

Speaker: Lutz Althüser (University of Münster)

20220907-althueser_RICAP22_XENONnT.pdf

14:20 Direct Detection of Dark Matter with DarkSide-20k

DarkSide run since mid 2015 a 50-kg-active-mass dual phase Liquid Argon Time Projection Chamber (TPC), filled with low radioactivity argon from an underground source and produced world class results for both the low mass ($𝑀<20$ 𝐺𝑒𝑉/c$^2$) and high mass ($𝑀 >100 $ 𝐺𝑒𝑉/𝑐$^2$) direct detection search for dark matter.
The next stage of the DarkSide program will be a new generation experiment involving a global collaboration from all the current Argon based experiments. DarkSide-20k, is designed as a 20-tonne fiducial mass dual phase Liquid Argon TPC with SiPM based cryogenic photosensors, and is expected to be free of any instrumental background for an exposure of >100 tonne x year. Like its predecessor, DarkSide-20k will be housed at the INFN Gran Sasso (LNGS) underground laboratory, and it is expected to attain a WIMP-nucleon cross section exclusion sensitivity of $7.4\times10^{−48}$ cm$^2$ for a WIMP mass of 1𝑇𝑒𝑉/𝑐$^2$ in a 200 t yr run. DarkSide-20k will be installed inside a membrane cryostat containing more than 700 t of liquid Argon and be surrounded by an active neutron veto based on a Gd-loaded acrylic shell. The talk will give the latest updates of the ongoing R\&D and prototype tests validating the initial design.
A subsequent objective, towards the end of the next decade, will be the construction of the ultimate detector, ARGO, with a 300 t fiducial mass to push the sensitivity to the neutrino floor region for high mass WIMPs.

Speaker: Paolo Agnes (RHUL/TRIUMF)

RICAP_pagnes.pdf

14:40 Dark matter direct search using cryogenic detectors

Unveiling the nature of dark matter is one of the main goals of modern particle physics. Dark matter direct detection experiments aim at solving the problem by measuring tiny energies deposited inside the detector by dark matter particles interacting with the target materials. Several techniques have been developed to explore the full parameter space of cross-sections and dark matter masses. In this talk, I will describe the status of the search for low-mass dark matter performed with cryogenic detectors operated at millikelvin temperature, which have reached energy thresholds down to $O(10)$~eV and sensitivity to dark matter masses down to $O(100)$~MeV/c$^2$. These experiments are all currently limited by an excess of events observed at low energies (below about 200~eV) of unknown origin. A worldwide collaborative effort has been established in the framework of the Excess Workshop to study these events, which are observed in an energy region never explored before by particle detectors. I will provide an update on the observations recently reported by the different collaborations during the latest Excess Workshop. Thanks to their versatility in the use of different target materials, cryogenic detectors have found application also in the cross-check of the annually modulating signal observed by the DAMA/LIBRA collaboration. I will conclude by presenting the status of the new cryogenic experiment using NaI targets.

Speaker: Vanessa Zema (Gran Sasso Science Institute)

RICAP_2022_VZema.pdf

15:00 Light dark matter detection: new ideas and new tools

I will discuss some possible ways of looking for sub-MeV dark matter using the emission of collective excitations in different media. In particular, I will discuss the possibility of probing spin-independent interactions using superfluid He-4, and spin-dependent ones using antiferromagnets (specifically, NiO and MnF2).
In doing that, I will employ a new theoretical tool, very familiar to high energy physicists, but just recently employed in the phenomenological study of phases of matter: effective field theories for the collective excitations of the material.

Speaker: Dr Angelo Esposito (Princeton IAS)

Ricap 2022.pdf

15:20 Direct Directional Dark Matter Search

In the last decades, the existance of Dark Matter (DM) has become well established, even though its nature is still elusive and unknown. The majority of the experiments searching for a direct signature of DM look at the energy of nuclear recoils induced by scattering with DM candidates. However, the motion of the Earth in the Galaxy produces an apparent wind of DM particles coming from the constellation Cygnus, making the direction of these nuclear recoils a very peculiar feature. The
measurement of the directional information would greatly benefit the field, for example by enabling the rejection of neutrino coherent scattering with nuclei (CEvENs) which will reduce the sensitivity of experiments that only measure energy. Moreover, the angular distribution is expected to have a clear dipole structure, key for positive identification of DM, and even DM astronomy. Directionality can also help in signal to background discrimination for faster discovery. We will review the present R&D on different experimental approaches that try to attain directional measurements and we will focus on those which have actually demonstrated directionality at the recoil energy of interest for DM, i.e. nuclear emulsion and gaseous Time Projection Chambers (TPC).
In the context of the gaseous TPC approach, we will illustrate the latest developments within the different existing projects, from gas and amplification stages optimization, to detector simulation, tracking algorithms and perferomance studies. We will also show the prospect of the realisation of CYGNUS, whose goal is to eventually establish, through a staged approach and installation in multiple underground laboratories, a Galactic Directional Recoil Observatory at the ton-scale.
CYGNUS could test the DM hypothesis beyond the Neutrino Floor and measure the coherent scattering of neutrinos from the Sun and possibly Supernovae.
During the talk, we will discuss the present state of the directional DM search, outline the status of current detectors, and review the recent results from R&D projects.

Speaker: Giorgio Dho (Istituto Nazionale di Fisica Nucleare)

Directional_Searches.pdf

15:40 Directionality for nuclear recoils in a liquid argon Time Projection Chamber

The Recoil Directionality project (ReD) within the Global Argon Dark Matter Collaboration aims to characterize the light and charge response of liquid argon (LAr) dual-phase Time Projection Chamber (TPC) to neutron-induced nuclear recoils. The main goal of the project is to probe for the possible directional dependence suggested by the SCENE experiment. Furthermore, ReD is also designed to study the response of a LAr TPC to very low-energy nuclear recoils. Sensitivity to directionality and to low-energy recoils are both key assets for future argon-based experiments looking for Dark Matter in the form of WIMPs. Furthermore, the ReD TPC uses all the innovative features of the design of the DarkSide-20k experiment: in particular the optoelectronic readout based on SiPM and the cryogenic electronics. It is thus a valuable test bench of the technology which is being developed for DarkSide-20k and for the future project Argo.

The first measurement of ReD consisted of the irradiation of a miniaturized LAr TPC with a neutron beam at the INFN, Laboratori Nazionali del Sud (LNS), Catania. The correlation of the ionisation and scintillation signals, which is a possible handle to measure the recoil direction of nuclei, was studied in detail for 70 keV nuclear recoils, using a neutron beam produced via the reaction p(7Li,7Be)n from a primary 7Li beam delivered by the TANDEM accelerator of LNS. A model based on directional modulation in charge recombination was developed to describe the correlation.

In addition, a dedicated measurement tailored to characterize the response of the TPC to very low-energy nuclear recoils (< 10 keV) is being currently performed at INFN Sezione di Catania, using neutrons produced by an intense Cf252 fission source.

In this contribution, we describe the experimental setup, the theoretical model, and the preliminary results from the data analysis.

Speaker: Noemi Pino

RICAP22_NPino.pdf

14:00 → 16:20 Multimessengers: 1

Conveners: Anna Franckowiak (Ruhr-Universität Bochum), Marica Branchesi (Istituto Nazionale di Fisica Nucleare)

14:00 Gravitational-Wave and Gamma-Ray Burst Joint Observations

I review the results of searches for gravitational-wave signals associated with gamma-ray bursts carried out in the first three observing runs of Advanced LIGO and Advanced Virgo. During this stretch of time, the spectacular GW170817-GRB 170817A event was observed, and constraints on the low-luminosity short gamma-ray burst population were placed. In the coming years, an increase in sensitivity of the gravitational-wave detector network is expected to yield more joint detections. I discuss the prospects for this scenario and show how the analysis of combined gravitational-wave and electromagnetic data from the same event can improve measurements of the inclination angle of the source, by breaking the degeneracy between the viewing and the jet opening angles.

Speaker: Prof. Francesco Pannarale (Sapienza – University of Rome & INFN Rome)

Pannarale_RICAP-22_Light.pdf

14:20 Neural networks for gravitational-wave trigger selection in single-detector periods

The search for gravitational waves transient sources with LIGO and Virgo is mainly limited by non-Gaussian transient noise artefacts coming from a wide variety of provenances, such as seismic, acoustic and electromagnetic disturbances. The contamination by these "instrumental glitches" can be partially mitigated by requesting temporal coincidence in two or more detectors as their accidental co-occurrence probability is low. When only one detector is operating this strategy cannot be used. During the past science runs, the single-detector time corresponds to a significant amount of observing time. Glitches vary widely in rate, duration, frequency range and morphology. For this reason, the statistical modelling of the non-Gaussian and non-stationary component of the noise has not been feasible, so far. We propose machine learning strategies, and in particular deep learning, to separate the glitches from the astrophysical signal. In this presentation, we show the performances of deep learning algorithms to select triggers and reduce the impact of transient noise during single-detector data taking periods.

Speaker: Agata Trovato (Istituto Nazionale di Fisica Nucleare)

Trovato_RICAP22.pdf

14:40 ELECTROMAGNETIC AND GRAVITATIONAL RADIATION DURING THE UNUSUAL FLASH IN THE ACTIVE CORE OF THE GALAXY 3C454. 3

Presents data analysis of long-term multi-frequency monitoring of the active galaxy nucleus in 3C 454.3 during unusual and prolonged flare, ongoing since the beginning of 2014 to 2020. The unique phenomenon may be due to a coincidence of the accretion disk (AD) plane of the Central supermassive black hole and the orbit of the companion at the time of precession of the Central body. Large and different scales fluctuations in the radiation flux density over the entire range of the electromagnetic spectrum during a long flare can be the result of various inhomogeneities of matter in AD. what can be used to study the distribution of matter in AD. Variants of radiation of electromagnetic and gravitational waves coming from 3C 454.3 in various States of object activity are considered.

Speaker: Alexandr Volvach

15:00 Detection prospects for multi-GeV neutrinos from collisionally heated GRBs

Neutrinos with energies ranging from GeV to sub-TeV are expected to be produced in Gamma-Ray Bursts (GRBs) as a result of the dissipation of the jet kinetic energy through nuclear collisions occurring around or below the photosphere, where the jet is still optically thick to high-energy radiation. So far, the neutrino emission from the inelastic collisional model in GRBs has been poorly investigated from the experimental point of view. In the present work, we discuss prospects for identifying neutrinos produced in such collisionally heated GRBs with the large volume neutrino telescopes KM3NeT and IceCube, including their low-energy extensions, KM3NeT/ORCA and DeepCore, respectively. To this aim, we evaluate the detection sensitivity for neutrinos from both individual and stacked GRBs, exploring bulk Lorentz factor values ranging from 100 to 600. As a result of our analysis, individual searches appear feasible only for extreme sources, characterized by gamma-ray fluence values at the level of Fγ ≥ 1e-2 erg cm−2. In turn, it is possible to detect a significant flux of neutrinos from a stacking sample of ~900 long GRBs (that could be detected by current gamma-ray satellites in about five years) already with DeepCore and KM3NeT/ORCA. The detection sensitivity increases with the inclusion of data from the high-energy telescopes, IceCube and KM3NeT/ARCA, respectively.

Speaker: Angela Zegarelli (Istituto Nazionale di Fisica Nucleare)

Zegarelli_LowENeutrinos_GRBs_RICAP2022.pdf

15:20 Searching for multi-messenger signals with the Pierre Auger Observatory

The Pierre Auger Observatory is the world’s largest experiment for the detection of ultra-high-energy (UHE) air showers, produced by particles with energies above ~$10^{18}$ eV. In addition to providing the most precise measurements of UHE cosmic rays properties, the Observatory exhibits also unprecedented sensitivities to UHE photons, neutrinos and neutrons, which makes it an excellent tool for multi-messenger observations.
Neutrinos and photons can be identified by looking at the longitudinal development and particle content of air showers. Besides, any kind of neutral particles, being undeflected by magnetic fields, can be identified by searching for a flux excess from a given direction. This technique has been successfully used e.g. to set the upper limits on the flux of Galactic neutrons.
Thanks to its discrimination capabilities, the Observatory provides some of the most stringent upper bounds at UHEs to the diffuse photon and neutrino fluxes and to the neutrino flux from point-like steady sources. In addition, upper limits to UHE neutrinos and photons coming from compact binary mergers has also been provided by the follow-up of gravitational waves detected by LIGO and Virgo. The capabilities of the Pierre Auger Observatory as a powerful multi-messenger observatory are also expected to further increase in the next future thanks to the on-going upgrade to AugerPrime.

Speaker: Eleonora Guido (Siegen Universität)

220725_RICAP_EGuido .pdf

15:40 Neutrinos from core-collapse supernovae at KM3NeT

On behalf of the KM3NeT Collaboration

The SN1987A core-collapse supernova was the first extragalactic transient source observed through neutrinos. The detection of the 25 associated neutrinos by the Super-Kamiokande, IMB and Baksan experiments marked the beginning of neutrino astronomy. Since then, neutrino telescopes have not been able to make another observation due to the remoteness of the sources. It is therefore essential to optimize the detection channel of sensitive detectors in case of an upcoming galactic core-collapse supernova. Neutrino observations would, in particular, provide first-hand information about the core-collapse mechanism as well as the behavior of particles in dense environments. In this contribution, we discuss how the unique structure of the optical modules of the KM3NeT neutrino experiment would allow to observe supernova neutrinos. We present KM3NeT’s sensitivity to galactic supernovae and describe its associated online alert system for multi-messenger studies. Finally, we discuss KM3NeT’s ability to infer the supernova evolution from the time profile of the associated neutrino emission.

Speaker: Meriem Bendahman

talk_RICAP_Bendahman.pdf

16:00 Exploiting synergies between neutrino telescopes for the next galactic core-collapse supernova

The core collapse supernova SN1987A was the first extra-galactic transient source ob- served in neutrinos, and 25 events detected by neutrino telescopes in the epoch marked the begin- ning of neutrino astronomy. Neutrino telescopes have not been able to make another supernova observation due to the remoteness of the sources. It is therefore essential to optimize the detection channel of sensitive detectors in case of an upcoming galactic core-collapse supernova. Relevant information on core-collapse supernova explosion can be extracted to study flavor evolution of neutrinos in dense environments. For certain massive supernovas, the magnetic field changes the accretion rate of matter and thus the production of neutrinos during the corresponding supernova explosion phase, but the way this accretion rate changes is not fully understood yet. In this contribution, we will present the potential of multi-detector analyses to enhance the scientific outputs from the next close-by core-collapse supernova by combining the expected light curves, neutrino detectors sensitive to different flavors such as in KM3NeT, DUNE, and DarkSide. We will study the constraints that could be set on the properties of the progenitor itself, such as its mass, as well as on the neutrino oscillation parameters. We will also present a study to better characterize the effect of magnetic field on neutrino observations by considering in particular the impact of dif- ferent magnetic field topologies on neutrino light curves for the KM3NeT, DUNE, and DarkSide experiments.

Speaker: Sonia El Hedri (APC, CNRS)

talk.key

talk.pdf

16:20 → 17:00 Coffee Break

17:00 → 18:40 Cosmic Rays: - 2

Conveners: Paolo Desiati (University of Wisconsin - Madison), Philipp Mertsch (TTK, RWTH Aachen University)

17:00 Probing Hadronic Interactions with Cosmic Rays

High-energy cosmic rays interact in the Earth's atmosphere and produce extensive air showers (EAS) which can be measured with large detector arrays at the ground. The interpretation of these measurements relies on sophisticated models of the EAS development which represents a challenge as well as an opportunity to test quantum chromodynamics (QCD) under extreme conditions. The EAS development is driven by hadron-ion collisions under low momentum transfer in the non-perturbative regime of QCD. Under these conditions, hadron production cannot be described using first principles and these interactions cannot be probed with existing collider experiments. Thus, accurate measurements of the EAS development provide a unique probe of multi-particle production in hadronic interactions. We will present an overview of current EAS measurements probing hadronic interactions and discuss various recent results. In addition, we will highlight the opportunities to test hadronic interactions with the next-generation cosmic ray experiments.

Speaker: Dennis Soldin (Karlsruhe Institute of Technology)

RICAP_dsoldin.pdf

17:20 Arrival Directions of Cosmic Rays above 32 EeV from Phase One of the Pierre Auger Observatory

The Pierre Auger Observatory has gathered an unprecedented dataset of ultrahigh-energy cosmic rays, thanks to its large aperture and more than 15 years of activity. We present here the highest energy events observed by the Observatory between 2004 and 2020, i.e., before the AugerPrime upgrade. With a cumulative exposure of ~120000 km2 sr yr, we collected more than 2600 events above 32 EeV. This energy region is the one of greatest interest for small- and intermediate-scale anisotropy searches. Firstly, because we expect the magnetic field deflection to be the smallest; secondly, the interaction of UHECRs with background photons, possible only at these energies, would limit the region where their sources lie. We present here a compendium of anisotropy studies, both blind and targeted, and show that evidence in excess of isotropy at intermediate angular scale is obtained at the 4-sigma significance level for cosmic-ray energies above ∼40 EeV.

Speaker: Lorenzo Caccianiga (Istituto Nazionale di Fisica Nucleare)

Caccianiga-RICAP2022.pdf

Caccianiga-RICAP2022.pptx

17:40 Astrophysical interpretation of Pierre Auger Observatory measurements of the UHECR energy spectrum and mass composition

We present a combined fit of a simple astrophysical model of Ultra-high-energy cosmic rays (UHECRs) sources to both the energy spectrum and mass composition data measured by the Pierre Auger Observatory. The astrophysical model we adopted consists of identical sources uniformly distributed in a comoving volume, where nuclei are accelerated with a rigidity-dependent mechanism. The fit has been performed at first for energies above 5 EeV, i.e., the region of the all-particle spectrum above the so-called “ankle” feature, and has then been extended to lower energies in order to include this feature. The fit results and their astrophysical implications in both cases are discussed.

Speaker: Mr Antonio Condorelli (Gran Sasso Science Institute)

Condorelli_RICAP.pdf

18:00 UHECR results of combined analyses of TA and Auger experiments

The origin of ultra-high-energy cosmic rays (UHECRs) is still unknown. Their sources are believed to be within the local universe (a few hundred megaparsecs), but deflections by intergalactic and Galactic magnetic fields prevent us from straightforwardly associating UHECRs to their sources based on their arrival directions, making their angular distribution mostly isotropic. At higher energies, the number of potential source candidates and the magnetic deflections are both expected to be smaller, but so is the available amount of statistics. Hence, it is interesting to perform searches for anisotropies using several different energy thresholds. With a threshold of 8 EeV a dipole modulation has been discovered, and with higher thresholds evidence is mounting for correlations with certain nearby galaxies. Neither of the two main UHECR detectors, the Pierre Auger Observatory and the Telescope Array project, has full-sky coverage. Full-sky searches require combining the datasets of both, and a working group with members of both collaborations has been tasked with this. We present an overview of the challenges encountered in such analyses, recent results from the working group, possible ways of interpreting them, and an outlook for the near future.

Speaker: Dr Armando di Matteo (INFN Torino)

slides.pdf

18:20 Magnetic Turbulence and the Origin of Cosmic-Ray Small-Scale Anisotropies

The arrival directions of cosmic rays are highly isotropic which is expected due to the interaction between these particles and magnetic turbulence in the interstellar medium. High-statistics observatories like IceCube and HAWC have however observed significant deviations from isotropy down to very small angular scales. Such small-scale anisotropies could not be predicted in the standard theory for Galactic cosmic-ray transport. In this talk, we will explore the recently developed theoretical framework to study small-scale anisotropies which takes into account correlations between fluxes of cosmic rays from different directions. The first analytical calculation of the angular power spectrum assuming a physically motivated model of the magnetic field turbulence will be presented and confronted with numerical simulations to provide more insights into the formation of cosmic-ray anisotropies due to magnetic turbulence.

Speaker: Vo Hong Minh Phan (TTK, Aachen)

Ricap.pdf

Test-Particle.mp4

17:00 → 18:40 Direct DM searches: - 2

Conveners: Elisabetta Baracchini (Istituto Nazionale di Fisica Nucleare), Ranny Budnik (Weizmann Institute of Science)

17:00 Searching for Light Dark Matter with Aligned Carbon Nanotubes: the ANDROMeDa Project

The ANDROMeDa (Aligned Nanotube Detector for Research On MeV Darkmatter) project aims to develop a novel Dark Matter (DM) detector based on carbon nanotubes: the Dark-PMT. The detector is designed to be sensitive to DM particles with mass between 1 MeV and 1 GeV. The detection scheme is based on DM-electron scattering inside a target made of vertically-aligned carbon nanotubes. Carbon nanotubes are made of wrapped sheets of graphene, which is a 2-dimensional meterial: therefore, if enough energy is transferred to overcome the carbon work function, the electrons are emitted directly in the infra-tube vacuum. Vertically-aligned carbon nanotubes have reduced density in the direction of the tube axes, therefore the scattered electrons are expected to leave the target without being reabsorbed only if their momentum has a small enough angle with that direction, which is what happens when the tubes are parallel to the DM wind. This grants directional sensitivity to the detector, a unique feature in this DM mass range. We will report on the construction of the first Dark-PMT prototype, on the establishment of a state-of-the-art carbon nanotube growing facility in Rome, and on the characterizations of the nanotubes with XPS and angular-resolved UPS spectroscopy performed in Sapienza University, Roma Tre University, and at synchrotron facilities. ANDROMeDa was recently awarded a 1M€ PRIN2020 grant with which we aim, over the course of the next three years, to construct the first large-area cathode Dark-PMT prototype with a target of 10 mg of carbon. The main focus of the R&D will be the development of a superior nanotube synthesis capable of producing optimal nanotubes for their use as DM target. In particular, the nanotubes will have to exhibit high degree of parallelism at the nanoscale, in order to minimize electron re-absorption.

Speaker: Federico Virzi

RICAP22_ANDROMeDa.pdf

17:20 Signature from Primordial Black Hole evaporation

Primordial Black Holes are hypothetical Black Holes formed in the very early universe and are potential Dark Matter Candidates. Focusing on the Primordial Black Holes mass range [$5\cdot10^{14}$−$1\cdot10^{17}$] g, we point out that their evaporation can produce detectable signals in existing experiments. First of all, we study neutrinos emitted by PBHs evaporation. They can interact through the coherent elastic neutrino-nucleus scattering producing an observable signal in multi-ton DM direct detection experiments. We show that using future experiments with higher exposure it will be possible to constraints the fraction of Dark Matter composed of Primordial Black Holes. Furthermore, we study the emission of a light Dark matter candidate endowed with large kinetic energies. Focusing on the XENON1T experiment, we show that these relativistic dark matter particles could give rise to signal orders of magnitude larger than the present upper bounds. The non-observation of such a signal can be used to constraints the combined parameter space of primordial black holes and sub-GeV dark matter.

Speaker: Roberta Calabrese (Istituto Nazionale di Fisica Nucleare)

RICAP 2022.pdf

17:00 → 18:40 Multimessenger - 2

Conveners: Anna Franckowiak (Ruhr-Universität Bochum), Marica Branchesi (Istituto Nazionale di Fisica Nucleare)

17:00 Experimental results on high-energy neutrino emissions from the Galaxy

The IceCube observatory, a cosmic neutrino detector located in the South Pole at a depth of about 3500 m, is the first and largest operating km3 neutrino telescope on the Earth. The IceCube’s discovery of neutrino events of cosmic origin in the TeV-PeV energy range stated the beginning of the age of neutrino astronomy.
The ANTARES telescope was the first operational Neutrino Telescope in the Mediterranean Sea built at a depth of 2500 m offshore of Toulon, France, searching for astrophysical neutrinos in the very high energy range. The ANTARES neutrino observatory provided a dataset which covers almost ten years of data acquisition, allowing for the study of galactic neutrino sources.
The KM3NeT collaboration started to build a multi-km3 neutrino telescope in the Mediterranean Sea. The telescope is composed of the ARCA detector, optimised for searches for high-energy neutrino sources in the Universe and it is under construction at the Capo Passero site, Italy, 80 km offshore at a depth of 3500 m; and the ORCA detector, located in the Toulon area, France, 40 km offshore at a depth of 2500 m, aimed at the determination of the mass hierarchy of neutrinos.
In this talk, an overview of the latest results and future perspectives from ANTARES, IceCube and KM3NeT Collaborations concerning the Galactic diffuse emission and astrophysical source studies will be presented.

Speaker: Giovanna Ferrara (INFN-LNS)

17:20 Search for high-energy neutrinos from the cores of Active Galactic Nuclei

IceCube is a cubic-kilometer Cherenkov telescope operating at the South Pole. In 2013, IceCube discovered high-energy astrophysical neutrinos and has more recently found compelling evidence for a flaring blazar being a source of high-energy neutrinos. However, as the gamma-ray blazars detected in the GeV energy band can only be responsible for a small fraction of the observed cosmic neutrino flux below 100 TeV, the sources responsible for the emission of the majority of the detected neutrinos are still unknown. In this contribution, we explore the possibility that the observed neutrino flux is produced in the cores of Active Galactic Nuclei (AGN), induced by accelerated cosmic rays in the accretion disk region. We present a likelihood analysis based on eight years of IceCube data, searching for a cumulative neutrino signal from three AGN samples created for this work. The neutrino emission is assumed to be proportional to the accretion disk luminosity estimated from the soft X-ray flux. We select AGN based on their radio emission, infrared color properties, and X-ray flux using the NVSS, AllWISE, ROSAT and XMM-SL2 catalogs. For the largest sample in this search, an excess of high-energy neutrino events with respect to an isotropic background of atmospheric and astrophysical neutrinos is found, corresponding to a post-trial significance of 2.60σ. If interpreted as a genuine signal with the assumptions of a proportionality of X-ray and neutrino fluxes, this observation implies that at 100 TeV, 27%-100% of the observed neutrinos arise from particle acceleration in the core of AGN.

Speaker: Federica Bradascio (IRFU, CEA Paris-Saclay, Université Paris-Saclay)

fbradascio_RICAP_2022.pdf

17:40 Searching for high-energy neutrinos from the most luminous supernovae with the IceCube Neutrino Observatory

The sources of the astrophysical neutrino flux discovered by IceCube remain for the most part unresolved. Extragalactic core-collapse supernovae (CCSNe) have been suggested as potentially able to produce high-energy neutrinos. In recent years, the Zwicky Transient Facility has discovered a population of exceptionally luminous supernovae, whose powering mechanisms have not yet been fully established. A fraction of these objects falls in the broader category of type IIn CCSNe, showing signs of interaction with a dense circumstellar medium. Theoretical models connect the supernova photometric properties to the dynamics of a shock-powered emission, predicting particle acceleration. In this contribution, we outline the plan for a search of high-energy neutrinos targeting the population of superluminous and Type IIn supernovae with the IceCube Neutrino Observatory.

Speaker: Massimiliano Lincetto (Ruhr-Universität Bochum)

202209_LINCETTO_RICAP2022.pdf

18:00 Near-future discovery of point sources of ultra-high-energy neutrinos

Upcoming neutrino telescopes may discover ultra-high-energy (UHE) cosmic neutrinos, with energies beyond 100 PeV, in the next 10--20 years. Finding their sources would expose the long-sought origin of UHE cosmic rays. We search for sources by looking for multiplets of UHE neutrinos arriving from similar directions. Our forecasts are state-of-the-art, geared at neutrino radio-detection in IceCube-Gen2. They account for detector energy and angular response, and for critical, but uncertain backgrounds. We report powerful insight. Sources at declination of −45$^\circ$ to 0$^\circ$ will be easiest to discover. Discovering even one steady-state source in 10 years would disfavor most known steady-state source classes as dominant. Discovering no transient source would disfavor most known transient source classes as dominant. Our results aim to inform the design of upcoming detectors.

Speaker: Damiano Fiorillo (Niels Bohr Institute, Copenhagen)

SlidesRICAP.pdf

18:20 The Gamma-Hadron Separation for Air Showers at the IceCube Neutrino Observatory

The IceCube Neutrino Observatory located at the geographic South Pole is composed of two detectors. One is the in-ice optical array, which measures high-energy muons from air-showers and charged particles produced by the interaction of high-energy neutrinos in the ice. The other is an array of ice-Cherenkov tanks at the surface, called IceTop, which is used both as veto for the in-ice neutrino measurements and for detecting cosmic-ray air showers. In the next decade, the IceCube-Gen2 extension will increase the surface coverage including surface radio antennas and scintillator panels on the footprint of an extended in ice optical array.
The combination of the current surface and in-ice detectors can be exploited for the study of cosmic rays and the search for PeV gamma rays. The in-ice detector measures the high-energy muonic component of air showers, whereas the signal in IceTop is dominated by the electromagnetic component.
The relative size of the muonic and electromagnetic components is different for gamma and hadron induced air showers. Thus, the gamma-hadron separation of cosmic rays is attempted using machine learning techniques including deep learning. Here, different approaches are presented. Finally, the prospects for the detection of PeV photons with IceCube-Gen2 will be discussed.

Speaker: Federico Bontempo (Karlsruher Institut für Technologie (KIT))

RICAP-2022_Bontempo.pdf

18:40 → 19:42 Poster Session

18:40 Axion and FIMP Dark Matter in a $U(1)$ extension of the Standard Model

In the Standard Model a Dark Matter candidate is missing, but it is relatively simple to enlarge the model including one or more suitable particles.
We consider in this paper one such extension, inspired by simplicity and by the goal to solve more than just the Dark Matter issue.
Indeed we consider a local $U(1) $ extension of the SM providing an axion particle to solve the strong CP problem and including RH neutrinos with appropriate mass terms. One of the latter is decoupled from the SM leptons and can constitute stable sterile neutrino DM.
In this setting, the PQ symmetry arises only as an accidental symmetry but its breaking by higher order operators is sufficiently suppressed to avoid introducing a large $ \theta $ contribution.
The axion decay constant and the RH neutrino masses are related to the same v.e.v.s and the PQ scale and both DM densities are determined by the parameters of the axion and scalar sector.
The model predicts in general a mixed Dark Matter scenario with both axion and sterile neutrino DM and is characterised by
a reduced density and observational signals from each single component.

Speaker: Sarif Khan (ITP, University of Goettingen)

18:42 Gamma-ray Interstellar Models in the inner Galaxy

Most analyses and interpretations of current high-quality data from the Fermi Large Area Telescope, especially in the Galactic center, highly rely on large-scale interstellar models of the diffuse emission, which are very uncertain. To complicate the picture, most of the current models officially used to analyze Fermi-LAT diffuse data usually do not take advantage of important constraints coming from radio and microwave available foreground data.

We present our approach and updates of our effort in coherently modeling the interstellar emission in the entire Galaxy by accounting for multifrequency observations from radio to gamma rays and for the latest accurate cosmic-ray direct measurements. This has clear implications for studies of the emission from the Galactic Center. For example, we found that models based on synchrotron observations in radio produce a more peaked inverse-Compton gamma-ray emission in the inner Galaxy with respect to the standard models used to analyze Fermi LAT data. Predictions for future missions at MeV, such as GECCO, ASTROGAM, and AMEGO are also shown.

This contribution is mainly based on our results from Orlando (2019) Physical Review D 99, 043007 and Orlando (2018) MNRAS 475, 2724.

Speaker: Elena Orlando (Istituto Nazionale di Fisica Nucleare)

Poster_CR_RICAP2022.pdf

18:44 The Gravitational Memory Effect

I n this dissertation we intend to study the background related to the memory effect that leads to "gravitational-wave memory effect" and two types of memory effect:(1) We intend to study a whole outline of what is memory effect.(2) We intend to solve the linear memory for N Gravitationally Unbound Particles where we will study different kinds of spherical harmonics,
mass quadrapole leading to linear memory effect :$${ {\Delta{h^{TT}_{jk}}}=\triangle{{\sum_{A=1}^{N}}}{\frac{4M_{A}}{r{\sqrt{1-v^{2}_{A}}}}[\frac{v^{j}_{A}v^{k}_{A}}{1-{{v_{A}.N}}}]^{TT}}}$$.Here N points from the source to the observer and ${\triangle}$ is the difference between late and early time values \cite{favata2010gravitational}.
Detailed calculation of derivation of the above equation is shown in our dissertation.

(3)Then we try to examine the memory effect for the individual radiated neutrinos[9] (4) Then we will discuss briefly about the introduction of non linear memory effect.

Speaker: Ms DEESHANI MITRA (St Xavier's College(Autonomous),Kolkata)

18:46 Overview of feebly interacting particle in indirect detection searches

Axion-like particles (ALPs) and other feebly interacting particles (FIPs) at sub-GeV scales has generated a lot of interest in the recent years.
Stars are good FIPs factories and consequently can be detected through their interaction with the interstellar matter or decay in standard particles. Many sources are taken as target, such as the sun and SNe.
I will illustrate how high-energy astrophysics observations can be exploited to set constraints in ALPs model and the proposal for future indirect detection experiments on MeV gamma ray energy range.

Speaker: Dr Federica Giacchino (INFN Roma Tor Vergata)

18:48 Short-Baseline neutrino oscillation searches with the ICARUS detector

The ICARUS collaboration employed the 760-ton T600 detector in a successful three-year physics run at the underground LNGS laboratories studying neutrino oscillations with the CNGS neutrino beam from CERN, and searching for atmospheric neutrino interactions. ICARUS performed a sensitive search for LSND-like anomalous νe appearance in the CNGS beam, which contributed to the constraints on the allowed parameters to a narrow region around 1 eV2, where all the experimental results can be coherently accommodated at 90% C.L. After a significant overhaul at CERN, the T600 detector has been installed at Fermilab. In 2020 cryogenic commissioning began with detector cool down, liquid Argon filling and recirculation. ICARUS has just started its first physics run, collecting neutrino events from the Booster Neutrino Beam and the NuMI off-axis. The main goal of the first year of ICARUS data taking will then be the definitive verification of the recent claim by NEUTRINO-4 short baseline reactor experiment both in the 𝜈μ channel with the BNB and in the 𝜈e with NuMI. After the first year of operations, ICARUS will commence its search for evidence of a sterile neutrino jointly with the SBND near detector, within the Short Baseline Neutrino (SBN) program. The ICARUS exposure to the NuMI beam will also give the possibility for other physics studies such as light dark matter searches and neutrino-Argon cross section measurements. The proposed contribution will address ICARUS achievements, its status and plans for the new run at Fermilab and the ongoing developments of the analysis tools needed to fulfil its physics program.

Speaker: Filippo Varanini (Istituto Nazionale di Fisica Nucleare)

18:50 Neutrino (new secret) Astronomy

The ICECUBE , ice cube km neutrino detector at South Pole, and its high energy starting events (HESE), either cascades (spherical shower) or longest muon tracks, well above several tens TeV or hundred TeV edges, had been claimed since 2013 to be the signature of a very possible Neutrino Astronomy. This new discover was not based on any neutrino self correlations, nor to any event clustering to relevant X,gamma or radio bright source, neither to GRBs or AGN powerfull flare connections. The 2013 new Astronomy had been based only on the sudden flavor change, from a muon track atmospheric (pion-Kaon decay) dominance (at TeVs energy), as a 0-1-0, electron-muon-tau neutrino ratio, to a cascade dominant HESE rate at hundreds TeV energy. These cascades had been suggested as being originated by a 1-1-1 "democratic" neutrino flavor component, made by cosmic astrophysical oscillations.
However the HESE tau neutrino signature, is , at present, nearly absent or negligible.
Moreover the same flavor change might be originated by a new atmospheric charmed component noise, leading to 1-1-0 flavor ratio, with almost absent tau flavor. Indeed the first ICECUBE HESE data 2013-2017, had shown such exact flavor component. Anyway, on September 2017 a possible AGN-ICECUBE track signal and connection had offered, to ICECUBE, more hopes of an astronomy discover. Last ICECUBE flavor map changed suddently and puzzling. Finally a very recent puzzling asymmetry are forcing us to stand for our different interpretation favoring the charmed atmospheric noise. In conclusion we suggest also a new (hidden and secret) Neutrino Astronomy screening, offering hope for a future filtered Neutrino Astronomy.

Speaker: Prof. Daniele Fargion

RICAP22-Fargion_85_v08.pdf

18:52 Cosmological Neutrinos, Dark Sector, and Particle Physics Synergies from the High-Redshift Cosmic Web

As Stage IV large-volume surveys are expected to reach an exquisite sub-percent level of statistical accuracy and precision in cosmological measurements, an accurate modeling of the dark sector is needed in order to obtain reliable likelihoods and unbiased cosmological parameters. This is particularly true at high-redshift and at small scales, where baryonic physics and feedback mechanisms can mimic subtle neutrino mass signatures or warm dark matter effects. We present the Sejong Suite, an extensive collection of high-resolution cosmological hydrodynamical simulations developed for the dark sector (massive neutrinos, dark radiation, warm dark matter). The resolution can be enhanced up to 110 billion particles in a [100 Mpc/h]^3 volume - optimal for the coming generation of cosmological surveys, including the Dark Energy Spectroscopic Instrument (DESI). The suite is grouped into 3 categories, addressing different science targets. In particular, we will focus on the Systematics Suite and present a number of effects that can impact parameter constraints, related to the modeling of additional species or intrinsic to the numerical nature of our simulations. We will also highlight the novelty of extended mixed scenarios for the dark sector, indicate ongoing improvements in numerical performance and resolution, and pinpoint interesting synergies with particle physics.

Speaker: Graziano Rossi (Sejong University)

18:54 AstroSAt observed broad-band Thermonuclear X-ray (Type-1) Bursts: 4U 1702-429

We present the detection of 3 thermonuclear type-1 X-ray bursts in the LMXB neutron star 4U 1702-429. The data with the AstroSat payload SXT and LAXPC instruments. It is characterized by the bursts having a sharp rise and slow decay, representing the burning of H/He mixed fuel. We perform the
time-resolved spectroscopy of bursts. We used three different techniques to analyze the bursts spectra. In the beginning, the assumptions have been followed that the presistent spectra remain constant during the bursts and reveal Planck’s feature black body temperature and flux throughout the bursts. Further, we used the scaling factor to the persistent emission (fa method) and found the fa value significantly immense at peak emission of the bursts. The elevation of fa indicates the expansion of pre-burst emission, especially near the peak. The flux ratio in both of phenomena introduce the new component in bursts emission. At last, we employed a thermal comptonization model to show the emission may be reprocessed from the star’s corona and disk.

Speaker: Yashpal Bhulla

18:56 The CYGNO experiment

The discrimination of nuclear recoils (NR) possibly induced by dark matter (DM) particles from the electronic recoils (ER) induced by the ordinary matter particles is one of the main experimental challenges of direct DM searches in the ${\rm GeV}/c^2$ mass region. Gaseous Time Projection Chambers (TPCs) with optical readout are a promising and innovative technique: the high granularity of the newest sCMOS light sensors, with the help of additional fast photosensors, allow high precision 3D position reconstruction with a good energy resolution and a sub-keV low energy threshold.
The Cygno collaboration is developing a gaseous TPC with optical readout filled with an atmospheric pressure He:CF$_4$ gas mixture, with a triple Gas Electron Multiplier (GEM) amplification stage. As a result, low energy events result in visible tracks, which are acquired by means of the sCMOS camera and the fast photosensors.

In this contribution, we present the main feature of the Cygno project, with particular focus on the current R&D activities and the future perspectives and goals. LIME, the largest 50 L prototype built so far, has been recently moved underground at the Laboratori Nazionali del Gran Sasso (LNGS) to evaluate the performances of this experimental approach in a low radioactive background environment. This campaign has the goal of proving the scalability of the Cygno detector approach to a bigger O(30 -100 ${\rm m}^3$) apparatus that could contribute to directional DM and neutrino searches.

Speaker: Stefano Piacentini (Istituto Nazionale di Fisica Nucleare)

Poster_RICAP2022.pdf

18:58 Needles in a haystack at Galactic level: Tracking millisecond pulsars responsible for the Fermi GeV excess

More than 10 years ago, an excess of $\gamma$-ray photons coming from the Galactic center was discovered in the Fermi-LAT data. First attributed to dark matter, it has since been shown that it should have at least a partial stellar origin. One intereseting explanation to the excess is the presence of a population of millisecond pulsars (MSPs) confined in the Galactic bulge. While unresolved in $\gamma$-rays, Berteaud et al. (2021) showed that some of these MSPs could already have been detected in past observations from the Chandra X-ray observatory and selected promising MSP candidates among unidentified Chandra-detected sources. In this poster, I will present our recent progresses in the selection of MSP candidates, unveiling compact objects and promising sources with X-ray and radio emission only. Our project motivated and obtained deep targeted radio observations which are essential for the identification of pulsars in the Galactic bulge.

Speaker: Joanna Berteaud (LAPTh, CNRS)

RICAP22_poster_Berteaud.pdf

19:00 The role of unresolved sources on the gamma-ray spectra of molecular clouds

Galactic diffuse emission in the MeV-GeV energy band is mostly contributed by the interaction of cosmic-ray (CR) nuclei with the dense interstellar medium (ISM). Observations of this radiation bring priceless information regarding the spatial and spectral distribution of CRs in the Galaxy far from the Solar System. Fermi-LAT observations of large-scale emission and of molecular clouds unveiled that in some locations, towards the inner Galaxy, the spectrum is harder than what was measured at Earth. In order to correctly interpret the data, however, one needs to differentiate the contribution of the "truly" diffuse emission, namely the one contributed by the bulk of CRs interacting with the ISM, from the contribution of unresolved sources. The latter constitute a non-negligible component that adds up to the large-scale gamma-ray flux. Previous studies constrained this contribution to be less than 20% at GeV energies, but they disregarded the contribution of pulsar wind nebulae (PWNe) in this band, as PWNe are mostly detected at higher energies. Newly developed theoretical models account for this source population and showed that their cumulative flux significantly shapes the spectrum of the diffusion emission, therefore challenging the conclusions about a spectral hardening of the CR flux towards the center of the Galaxy. In light of the newest theoretical results, we discuss here the contribution that this unresolved source population provides to the observed spectra of the diffuse emission with a particular focus on molecular clouds. Being this contribution subject to the observed angular size, we expect it to be less important when observing smaller regions. We discuss the influence of unresolved sources on clouds of different sizes and locations and give a prescription on how to choose the regions to target in order to have an unbiased determination of the "truly" diffuse emission.

Speaker: Vittoria Vecchiotti

19:02 Cosmic ray clouds escaping the middle-age supernova remnant W44

We present the morphological and spectral analysis of Fermi-LAT data of the middle-aged supernova remnant (SNR) W44 and the massive molecular gas complex that surrounds it. The derived spectral energy distribution of the SNR, derived over three decades is improved, with respect to previous observations, both at low (< 100 MeV) and at higher energies (> 100 GeV) allowing us to strongly
constrain the hadronic origin of the emission. We also unveil the presence of two extended γ-ray structures located at two opposite edges of the remnant along its major axis. These two sources do not coincide with any peak in the gas distribution, therefore are interpreted as “CR clouds”, namely as regions of enhanced CR density, consisting of particles that escaped collectively from the remnant along the magnetic field.

Speaker: Giada Peron (Max Planck Institute of Nuclear physics)

Cosmic_ray_clouds_escaping_from_the_middle_aged_snr_W44.pdf

19:04 Sensitivity of the KM3NeT detector to a flux of nuclearites

Over the past decades, theories have predicted the existence of heavy compact objects containing an extremely dense form of exotic matter named Strange Quark Matter (SQM). This type of hypothetical matter is composed of nearly equal quantities of up, down and strange quarks and is supposed to be the ground state of Quantum Chromodynamics. Nuclearites are the massive component of SQM particles. Some studies show that nuclearites heavier than 10¹³ GeV with velocities of approximately 250 km/s could reach the Earth and could be observed by neutrino telescopes. KM3NeT is a network of deep-sea neutrino telescopes located in the Mediterranean Sea, dedicated to the search for high-energy cosmic neutrinos and the study of neutrino properties. The KM3NeT detector consists of two large volume photomultiplier (PMT) arrays, ARCA (Astroparticle Research with Cosmics in the Abyss) and ORCA (Oscillation Research with Cosmics in the Abyss), placed at the bottom of the Mediterranean Sea in Italy (3500 m) and France (2475 m), respectively. The ARCA configuration will be composed of two building blocks with 115 Detection Units (DUs), each DU containing 18 Digital Optical Modules (DOMs), while ORCA will be composed of only one building block. ARCA is optimized for the detection of high energy neutrinos, in the range TeV-PeV. The main goals for this detector are to identify and study the high energy cosmic neutrino sources, as well as to validate the diffuse neutrino flux measured with the IceCube detector. ORCA is a more compact detector that is optimized for the study of atmospheric neutrinos, having the exciting purpose to study the neutrino oscillations in order to determine the neutrino mass hierarchy. The detectors are currently under construction and they are already taking data with the first installed lines. Nuclearites can be detected by the instrumented area through the visible blackbody radiation generated along their path inside or near the instrumented area. Neutrino telescopes represent a powerful tool for the study of nuclearites due to their large sensitive volumes and to their deep-sea locations. The detection and characterisation of this type of particles could make breakthrough discoveries in the fundamental physics and could provide information on the Dark Matter component of the Universe. In this contribution, Monte Carlo simulations are used in order to evaluate the detector response to nuclearites and preliminary results on the sensitivities of the KM3NeT neutrino telescope for a flux of down-going nuclearites are presented.

Speaker: Alice Paun (Institute of Space Science, Romania)

19:06 The GECCO Mission at MeV energies

We present an innovative mission concept that builds upon the heritage of past and current missions improving the sensitivity and, very importantly, the angular resolution. This consists in combining a Compton telescope and a coded-mask telescope. The Galactic Explorer with a Coded Aperture Mask Compton Telescope (GECCO) is a novel concept for a next-generation telescope covering hard X-ray and soft gamma-ray energies. With the unprecedented angular resolution of the coded mask telescope combined with the sensitive Compton telescope, a mission such as GECCO can disentangle the discrete sources from the truly diffuse emission.
We present the GECCO mission and its science as recently published in JCAP07(2022)036.

Speaker: Elena Orlando (Istituto Nazionale di Fisica Nucleare)

Poster_RICAP2022_GECCO.pdf

19:08 Coherent elastic neutrino-nucleus scattering in argon with a scintillating bubble chamber

The Scintillating Bubble Chamber Collaboration (SBC) is developing a liquid-noble detector ideal for GeV-mass WIMP searches and coherent elastic neutrino-nucleus scattering (CE$\nu$NS) detection. The detector is now being commissioned at Fermilab and consists of a 10-kg bubble chamber using liquid argon with the potential to reach and maintain sub-keV energy thresholds. This detector will combine the event-by-event energy resolution of a liquid noble scintillation detector with the world-leading electron-recoil discrimination capability of the bubble chamber. The physics reach of this detector using CE$\nu$NS will be presented in this poster and includes the sensitivity to the weak mixing angle, neutrino magnetic moment, and a light Z$^\prime$ gauge boson mediator, in addition to other sensitivity to New Physics scenarios like light scalar mediators, sterile neutrino oscillations, unitarity violation, and non-standard interactions.

Speaker: Ernesto Alfonso Pita (Instituto de Física, Universidad Nacional Autónoma de México)

RICAP_2022_E_Alfonso_Pita.pdf

19:10 Photon-mediated dark-matter-nucleus interactions in the PICO-60 C3F8 bubble chamber

The PICO-60 C3F8 dark matter detector was a bubble chamber consisting of a fused silica inner vessel filled with 52 kg of C$_3$F$_8$ in a superheated state operating at 2.45-keV and 3.29-keV thermodynamic thresholds, reaching exposures of 1404-kg-day and 1167-kg-day, respectively. This bubble chamber was operated two km deep underground at SNOLAB, in Sudbury, Ontario in Canada. These two searches established the most stringent direct-detection constraints to date on the WIMP-proton spin-dependent cross-section at 2.5$\times10^{−41}$ cm$^2$ for a 25 GeV/c$^2$ WIMP. In this poster, the latest results from the PICO-60 detector will be presented, establishing coupling limits for photon-mediated dark matter-nucleus interactions using non-relativistic contact operators in an effective field theory framework.

Speaker: Alejandro Santiago García Viltres (Universidad Nacional Autónoma de México)

RICAP_2022-A-S_Garcia_Viltres.pdf

19:12 Paleo-detectors to investigate the flux of cosmic rays in the past

Interactions between secondary cosmic rays and nuclei in natural minerals can cause nuclear recoils that leave tracks in the material structure. Such defects, which can also be caused by other astroparticles, can be preserved for up to some Gyr, making these useful “time machines” for the study of the history of astrophysical messengers. These so-called "Paleo-detectors" have been proposed as alternatives to standard rare-events detectors as they feature huge accumulated exposure times even for small masses of material. We here present a different approach: trying to use them as probes for past fluxes of cosmic rays. In particular, we will show the case study of the Messinian salinity crisis, a period of draining of the Mediterranean Sea which is interestingly coincident with the estimated age of the Fermi Bubbles, around 5.5 Myr ago, when our Galaxy might have been active. Greatly increased cosmic ray acceleration near the Galactic Center could have left traces in the evaporites, mainly Halite, created with the evaporation of the sea and exposed directly to secondary cosmic rays. These mineral structures were then covered during the sudden reflooding of the Mediterranean basin 5.3 Myr ago; the cosmic ray flux information then remained frozen due to the shielding of the massive body of water, possibly retaining information on the flux of particles at ground at that epoch.

Speaker: Lorenzo Caccianiga (Istituto Nazionale di Fisica Nucleare)

19:14 Neutrino predictions from choked Gamma-Ray Bursts and comparison with the observed cosmic diffuse neutrino flux

The strong constraints from the Fermi-LAT data on the isotropic gamma-ray background suggest that the neutrinos observed by IceCube might possibly come from sources that are hidden to gamma-ray observations. A possibility emerged in recent years is that neutrinos may come from jets of collapsing massive stars which fail to break out of the stellar envelope, and for this reason they are known as choked jets, or choked Gamma-Ray Bursts (GRBs). We here show our predictions of neutrino flux and spectrum expected from these sources, focusing on Type II SNe, through detailed calculations of pγ interactions and accounting for all the neutrino production channels and scattering angles. We provide predictions of expected event rates for ANTARES, IceCube, and the next generation neutrino telescope KM3NeT. We also compute the contribution of the choked GRB population to the diffuse astrophysical neutrino flux, thus providing constraints on the local rate of this source population as to reproduce the observed neutrino flux.

Speaker: Angela Zegarelli (Istituto Nazionale di Fisica Nucleare)

PosterRICAP2022_chokedGRBs_Zegarelli.pdf

Thursday, 8 September

09:00 → 11:00 III Plenary: chair Dafne Guetta

09:00 The dawn of high energy neutrino astronomy

Current knowledge of the Universe is based on information carried by electromagnetic radiation, gravitational waves, neutrinos, and cosmic rays. For over a century, scientists have observed cosmic rays, but the understanding of their place of production is limited. As a product of cosmic ray interaction, neutrinos can shed light on the extreme part of the Universe. IceCube Neutrino Observatory has been leading neutrino astronomy research over the last ten years and is the only observatory with the exposure to detect high-energy neutrinos beyond Earth's atmosphere.
This presentation will highlight the IceCube observations, including new recent results, and anticipate future opportunities.

Speaker: Prof. Elisa Resconi (Technical University of Munich)

RICAP-2022-Resconi.pdf

RICAP-2022-Resconi.pptx

09:30 The ANTARES neutrino telescope

After more than fifteen years, the ANTARES detector stopped its data taking last February and is currently being dismissed. ANTARES has marked the history of undersea neutrino telescopes, demonstrating the feasibility of this technology and paving the way to neutrino telescopes of the new generation, in particular to the KM3NeT-ARCA and ORCA detectors, at present under construction in two deep sites of the Mediterranean Sea. Thanks to its location in the Northern hemisphere and to excellent optical properties of sea water, it offered a privileged point of view towards the Galactic center and the Galactic plane. Despite its small size, it provided important contributions to constrain and limit theoretical models. ANTARES data have been used to cover a wide range of studies ranging from the search of a diffuse flux of high energy neutrinos to the identification of neutrino sources to the search for dark matter candidates. Moreover, ANTARES has been involved in a rich program of multi-messenger activities, searching for neutrinos in space/time coincidence with gravitational waves events and with transient electromagnetic emissions as well as sending alerts to a wide network of observatories all over the world.
In this talk the scientific adventure of ANTARES will be shortly reviewed and the main scientific results will be presented and discussed.

Speaker: Annarita Margiotta (Istituto Nazionale di Fisica Nucleare)

Talk_RICAP_ANTARES_Margiotta.pdf

10:00 KM3NeT: status of construction and recent physics results

KM3NeT is a multi-site detector devoted to the detection and study of cosmic neutrinos and their sources in the Universe, and to the measurement of the neutrino oscillation parameters. Two underwater detectors are under construction in the Mediterranean Sea, ARCA (Portopalo di Capo Passero, Italy) and ORCA (Toulon, France), optimized respectively for neutrinos in the energy range of 1 TeV-100 PeV and 10 GeV-10 TeV. The mass construction of the detectors has started, and a long-term plan for the completion is in place. Currently, 19 (7) Detection Unit are active in the ARCA (ORCA) site. In this talk I will report the main physics results obtained with ARCA and ORCA, in their partial configurations. The KM3NeT alert system will be discussed, in the context of a multi-messenger approach. Finally, an overview of the expected performances of the full detectors will be given.

Speaker: Simone Biagi (Istituto Nazionale di Fisica Nucleare)

KM3NeT-Biagi_low.pdf

10:30 Electromagnetic transient surveys: A key to progress in HE neutrino astronomy

The detection of high energy (HE) extra-Galactic neutrinos by IceCube demonstrates the potential held by neutrino astronomy for identifying the sources of HE cosmic rays and for providing unique constraints on models of high energy astrophysical sources. Fulfilling this potential relies on the electromagnetic identification of the neutrino sources. I will discuss what we have learned from detecting HE neutrinos and what is required to make significant progress, particularly towards enabling electromagnetic identification of the sources.

Speaker: Eli Waxman (Weizmann Institute)

2022 09 RICAP Waxman Nu-EM.pdf

11:00 → 11:30 Group photo and Coffe break

11:30 → 12:30 IV Plenary Session chair Antonio Capone

IV Plenary Session

11:30 LHAASO Status and Highlights in gamma-ray Astronomy

The Large High Altitude Air Shower Observatory (LHAASO) as the largest ground based Gamma Ray detector array is built up. The full array has been operated for one year. Many VHE gamma ray sources has been observed including well known sources such as the Crab and Mkr421. With many sources found having strong emission of gamma rays in UHE(> 0.1 PeV) band, LHAASO starts the era of the UHE gamma ray astronomy. With its unprecedented sensitivity at energies above 10 TeV and extremely high background rejection capability, super-PeV gamma-like events, including the record high energy of 1.4 PeV, are detected first time in history. With also measured SEDs of several galactic gamma sources above 0.1 PeV, LHAASO reveals that our galaxy is full of PeVatrons. The extreme features of the electron PeVatron inside the Crab pose strong challenges to models and even more fundamental theories. Those discoveries enable an exploring for hadronic PeVatrons, i.e. origins of cosmic rays. The highest energy photons provide opportunities of checking for validity of fundamental rules, such as the Lorentz Invariance.

Speaker: Zhen Cao (Institute of High Energy Physics, Beijing, China)

LHAASO-2022-RICAP.pptx

12:00 Cosmic ray acceleration in galactic sources

Massive stars blow powerful winds and eventually explode as supernovae. By doing so, they inject energy and momentum in the circumstellar medium, which is pushed away from the star and piles up to form a dense and expanding shell of gas. Particles can be accelerated at both stellar wind termination shocks and at supernova remnant shocks. I will review these acceleration processes, together with their radiative signatures.

Speaker: Stefano Gabici (APC)

gabici.pdf

12:30 → 13:30 Lunch Break

13:30 → 15:30 Extra-Galactic sources: - 1

Conveners: Dario Gasparrini (Istituto Nazionale di Fisica Nucleare), Elisa Prandini (University of Padova and INFN)

13:30 Extragalactic sources: phenomenology and open questions

Active Galactic Nuclei have been historically divided into Radio-Loud and Radio-Quiet. I will discuss the most recent results on the main physical mechanisms acting in these two classes of sources and their contribution to the high energy emission.

Speaker: Francesca Panessa (IAPS/INAF)

RICAP22_Panessa.pdf

13:50 The gamma-ray emission of Galaxy Outflows

Galaxies display a variety of outflows, which are detected from near the central super-massive black hole to the entire host. These outflows are often powerful enough to unbind, if sustained over time, the gas of these galaxies. Propagating through the galaxy, the outflows should interact with the interstellar medium creating a strong shock, similar to those observed in supernovae explosions, which is able to accelerate charged particles to high energies. Here we report the Fermi Large Area Telescope detection of gamma-ray emission from galaxies with two different types of outflows: ultrafast and molecular outflows. In this talk I will review our findings and discuss them in terms of particle acceleration at the shock front.

Speaker: Ajello Marco (Clemson University)

Outflows_RICAP.pdf

Outflows_RICAP.pptx

14:10 VHE extragalactic results and perspectives from ground based instruments

The very high energy (VHE, E>100 GeV) extragalactic sky is being slowly populated, nowadays it is composed of around 90 targets. Blazars are clearly the dominant population, while some radio galaxies and gamma-ray bursts are spicing the study of the extreme Universe. The study of the intrinsic characteristics of their relativistic jets allow us to test extreme physical process, as well as can be used as cosmic lighthouses for the study of cosmological backgrounds tightly connected to the Universe evolution as the extragalactic background light (EBL) and the intergalactic magnetic field (IGMF). Of particular interest is the study of fast variability, pointing to extreme acceleration processes and, together with the study of the multi-frequency information might point to the need to more complicated structured jets w.r.t. the classical models. The detecion of flat spectrum radio quasars (FSRQs) allow us to test the AGN structure and its influence in the gamma-ray observations. Some transitional VHE blazars are being detected, sharing some characteristics across FSRQs and BL Lac objetcs. The hunting of extreme blazars is also one of the key topics to be investigated, as their emission peaks should be located at the VHE band. In this contribution, we will briefly mention the current status of these hot topics together with some perspectives for the future ground based gamma-ray instruments.

Speaker: Josefa Becerra González (Instituto de Astrofísica de Canarias)

jbecerra_ricap.pdf

14:30 Gamma-ray and neutrino emissions from star-forming and starburst galaxies

Experimental observations have demonstrated a strong correlation between star-forming processes and gamma-ray luminosities. However, the very nature of these emissions is still under debate. Certainly, Star-forming and Starburst Galaxies (SFGs and SBGs) are well-motivated astrophysical candidates to emit gamma-rays and neutrinos, through hadronic collisions. In this talk, I will present several updates on their non-thermal radiations, revisiting both their point-like and cumulative (diffuse) emission properties. From the point-like side, I will discuss the potentialities of future gamma-ray (CTA, SWGO) and neutrino (KM3NeT/ARCA, IceCube-gen2) telescopes to quantitively scrutinize their gamma-ray and neutrino expectations from different cosmic-ray transport models. From the diffuse perspective, I will investigate a model based on a data-driven blending of spectral indexes, thereby capturing the observed changes in the properties of individual emitters. Strikingly, SFGs and SBGs can explain up to 40% of the diffuse HESE data, while remaining consistent with gamma-ray limits on non-blazar sources.

Speaker: Antonio Ambrosone (Istituto Nazionale di Fisica Nucleare)

prsentation_RICAP_Ambrosone.pdf

14:50 KM3NeT/ARCA expectations for starburst galaxies observation

On behalf of the KM3NeT Collaboration

In this contribution, we present the expectations of the full detector KM3NeT/ARCA for particular Starburst Galaxies signals, both as a diffuse signal and as point-like excess. To describe the diffuse flux, we use a recent theoretical model, also developed by some of the authors of this contribution, which implements a “blending” of spectral indexes to describe the high energy spectral energy distribution. For the point-like search approach, we considered the most promising local starburst galaxies to be observed as point-like neutrino excesses: NGC 1068, the Small Magellanic Cloud and the Circinus Galaxy. For the diffuse analysis, we provide the 5-year differential sensitivity for two ARCA building blocks, considering both track and shower events, in the range of 100 GeV - 10 PeV. For the point like analysis, we provide the 6-year differential sensitivity for two ARCA building blocks, only considering track events in the range of 1 TeV - 10 PeV. We found that ARCA has the potential to constrain the selected phenomenological scenarios, showing the minimum of the sensitivity where the theoretical spectral energy distributions are expected to peak. This could provide evidence of the link between star-forming processes and hadronic emissions.

Speaker: Walid Idrissi Ibnsalih (Istituto Nazionale di Fisica Nucleare)

RICAP_SBGs_defenitive.pdf

13:30 → 15:30 Galactic Sources: - 1

Conveners: Alison Mitchell, Silvia Celli (Istituto Nazionale di Fisica Nucleare)

13:30 Particle acceleration and radiation in stellar clusters

The search of Galactic sources able to accelerate cosmic rays (CR) up to energies of ~PeV (the so-called PeVatrons) is one of the most active research topic in the field of high energy Astrophysics. For decades supernova remnants have been considered the most promising candidates but deep gamma-ray observations and theoretical developments suggest that such sources are unable to produce PeV CRs at the required flux. Young massive stellar clusters (YSC) may represent an interesting alternative. In fact several YSC are associated with gamma-ray sources and, at least in one case (the Cygnus cocoon), photons up to 1.4 PeV have been detected by LHAASO, suggesting the presence of hadrons beyond PeV energies. I will present a theoretical model based on diffusive shock acceleration at stellar winds which can account for the gamma-ray emission from YSC.

Speaker: Giovanni Morlino (INAF/Oss. Astrofisico di Arcetri)

Morlino-Stellar clusters.pdf

13:50 Gamma-ray observations of the massive stellar cluster Westerlund I with HESS

Young massive stellar clusters are extreme environments, and potentially provide the means for efficient particle acceleration. Indeed, they are increasingly considered as being responsible for a significant fraction of cosmic rays (CRs) accelerated within the Milky Way. Westerlund 1, the most massive known young stellar cluster in our Galaxy is a prime candidate for studying this hypothesis. While the very-high-energy gamma-ray source HESS J1646–458 has been detected in the vicinity of Westerlund 1 in the past, its association could not be firmly identified.

With the aim to identify the physical processes responsible for the gamma-ray emission of HESS J1646–458, we used a significantly enlarged set of 164 hours of data recorded with the High Energy Stereoscopic System (H.E.S.S.) and carried out a deep spectromorphological study of the region. We furthermore employed H I and CO observations of the region to infer the presence of gas that could serve as target material for interactions of accelerated CRs.

In this presentation, an insight into the gamma-ray data analysis and the corresponding spectromorphological analysis results is given. Different acceleration sites within the region, including Westerlund 1, and mechanisms are addressed and their potential to contribute to the observed gamma-ray emission is evaluated.

Speaker: Andreas Specovius (FAU Erlangen-Nürnberg (ECAP))

ricap22_specovius.pdf

14:10 Unveiling the cosmic-ray density with gamma-ray observations of molecular clouds

High-energy $\gamma$ rays, originating from interactions of cosmic rays (CRs) with the interstellar medium (ISM), carry direct information about the spatial and spectral distribution of these relativistic particles. Observations of Fermi-LAT of the diffuse gas unveiled a higher emissivity and a harder spectral index in the inner part of the Galaxy. Analyses of the diffuse emission however are performed on a large spatial scale, usually of several kpc$^2$ and therefore are subject to contamination both of mis-modeled sources and of unresolved sources. Giant Molecular clouds instead are a unique tool, which can be used as ‘barometer’ to infer the cosmic-ray density point by point, in distant and small regions of the Galaxy. Their enhanced density (n$_H$ > 100 cm$^{-3}$), compared to the diffuse gas, allows us to derive the CR energy density on scales comparable to the size of the clouds (10--100 pc). We report here the results of the analyses of Fermi-LAT Pass8 data, obtained in the direction of molecular clouds located in the entire galactic disk from 0.1 kpc to 12 kpc from the Galactic Center (GC). The CR densities measured at the locations of these clouds have a high degree of fluctuation and are not always compatible with the values derived from the diffuse gas. I will discuss the observational results and their implications as well as the prospects for future observations.

Speaker: Giada Peron (Max Planck Institute of Nuclear physics)

RICAP2022.pdf

14:30 Ultra-high energy inverse Compton emission from Galactic electron accelerators

It is generally held that >100 TeV emission from astrophysical objects unambiguously demonstrates the presence of PeV protons or nuclei, due to the unavoidable Klein–Nishina suppression of inverse Compton emission from electrons. However, in the presence of inverse Compton dominated cooling, hard high-energy electron spectra are possible. We show that the environmental requirements for such spectra can naturally be met in spiral arms, and in particular in regions of enhanced star formation activity, the natural locations for the most promising electron accelerators: powerful young pulsars. Leptonic scenarios are applied to gamma-ray sources recently detected by HAWC and LHAASO. We show, that these sources can indeed be explained by inverse Compton emission.

Speaker: Mischa Breuhaus

RICAP_2022_Mischa_Breuhaus.pdf

14:50 Gamma-gamma absorption in the Galactic Center

The Galactic Center (GC) is an intriguing lab for non-thermal astrophysics due to its proximity and its transparency in radio, X-ray and γ bands. In addition to hosting a supermassive black hole, a compact luminous young star cluster, and the circumnuclear ring, the central few parsecs of the Milky Way are also notable for hosting a source of cosmic rays extending up to PeV in energy $-$ the first known Galactic Pevatron. However, the spectrum of the brightest γ source, possibly associated with SgrA*, shows a clear cut-off at 1-10 TeV in the H.E.S.S. data. Since the H.E.S.S. PSF FWHM is several arcminutes wide, a possible explanation would be the γ-photon interaction with the IR radiation field in the central 2-3 arcminutes. To investigate the absorption by pair creation, I computed the mid-IR 3d emissivity and thus the mid-IR radiation field with an arcsecond resolution in the central few parsecs, deriving the total opacity given a modeled γ source. I will present the latest results, showing how this method could potentially determine the accelerator position with unprecedented precision in γ astronomy. Lastly, I will quickly go through a few possible applications of my 3d-model for future investigations of the Galactic Center at very-high energies.

Speaker: Francesco Conte (Max Planck Institut for Nuclear Physics, Heidelberg)

Conte_RICAP_Sept22.pdf

15:10 The Galactic diffuse gamma-ray emission meets the PeV frontier

The Tibet ASγ and LHAASO collaborations recently provided the first evidence of a diffuse γ-ray emission in the Galaxy up to the PeV from the Galactic plane. Due to the challenges this imposes to current theoretical models it is crucial to carefully study different scenarios of diffuse γ-ray production, specially towards the centre of the Galaxy. In particular, the current models of diffuse emissions struggle to reproduce ASγ and LHAASO data.
In this contribution, we show that these measurements seem to favour an inhomogeneous transport of cosmic rays throughout the Galaxy, specially motivated by the measurements of the Fermi-LAT detector. Moreover, we discuss the relevance of non-uniform cosmic-ray transport scenarios and the implications of these results for cosmic-ray physics and show that the energy spectra measured by Tibet ASγ, LHAASO, ARGO-YBJ and Fermi-LAT in several regions of the sky can be consistently described in terms of the emission arising by the Galactic cosmic-ray ``sea''. We also comment on the impact of other possible contributions, as the γ-ray emission from TeV halos or unresolved sources.

Speaker: Prof. Dario Grasso (University of Pisa)

13:30 → 15:30 Indirect Dark Matter searches

Conveners: Carlos Perez de los Heros (Uppsala University), Manuela Vecchi

13:30 Pierre Auger Observatory and Super Heavy Dark Matter

We will review the theoretical basis and models of Super Heavy Dark Matter and the search for signatures of their decay in the Auger Observatory data. From the lack of signal, it is possible to derive very stringent limits on the model parameters that connect the Auger Observatory data with cosmological models of the early universe and physics beyond the standard model.

Speaker: Roberto Aloisio (INFN)

13:50 The GAPS experiment: low-energy antinuclei measurements for dark matter searches.

GAPS (General Anti-Particle Spectrometer) is a balloon-borne experiment designed to measure low-energy (< 0.25 GeV/n) cosmic antinuclei (i.e., antiprotons, antideuterons, and antihelium nuclei) as a signature of dark matter annihilation or decay. The experiment will conduct a series of long-duration balloon flights at high altitudes from Antarctica. According to viable beyond-the-Standard Model theories, the predicted dark matter signal in the low-energy antideuterons and antihelium nuclei channels is several orders of magnitude higher than the astrophysical background. The instrument is composed of a Si(Li) tracker surrounded by a Time-of-Flight system made of plastic scintillators. GAPS uses the novel exotic-atom detection technique in which an antinucleus is captured by the tracker material and forms an exotic atom. This excited exotic atom decays emitting X-rays at specific energies defined by the atomic transitions and annihilates emitting secondary particles (mainly pions and protons). The measured quantities (e.g., dE/dx, time of flight, annihilation vertex position, X-rays energies, etc.) allow for identifying antinuclei with high precision. This talk will briefly review the theoretical implications behind the experiment and report on the construction and performance status of the GAPS instrument.

Speaker: Nadir Marcelli (Istituto Nazionale di Fisica Nucleare)

GAPS_RICAP2022.pdf

14:10 Shedding light on low-mass subhalo survival with numerical simulations

In this work, we carry out a suite of specially-designed numerical simulations to shed further light on dark matter (DM) subhalo survival at mass scales relevant for gamma-ray DM searches, a topic subject to intense debate nowadays. Specifically, we have developed and employed an improved version of DASH, a GPU $N$-body code, to study the evolution of low-mass subhaloes inside a Milky Way-like halo with unprecedented accuracy. We have simulated subhaloes with varying mass, concentration, and orbital properties, and considered the effect of the gravitational potential of the Milky Way galaxy itself. In addition to shedding light on the survival of low-mass galactic subhaloes, our results will provide detailed predictions that will aid current and future quests for the nature of DM.

Speaker: Alejandra Aguirre-Santaella (Instituto de Física Teórica UAM-CSIC)

AAS-survival-ricapsep.ppsx

14:30 Primordial Black Holes as Dark Matter candidates: constraints from the diffuse MeV emission

For more than 20 years, the Compton telescope (COMPTEL) had provided the best measurments of the Galactic diffuse MeV spectrum. Recently, our analysis of 16 years of data from the SPectrometer on INTEGRAL (SPI) [Siegert et. al (2022)] measured this emission with a higher signal-to-noise ratio. At MeV energies, the dominant contribution to the diffuse emission comes from inverse Compton scattering of low energy photons by cosmic-ray electrons. Nonetheless, sub-dominant emission from Primordial Black Hole (PBH) Dark Matter (DM) can be searched for in these data. Hypothetically formed from the collapse of overdensities before Big Bang nucleosynthesis, PBHs are interesting candidates for DM in the $\Lambda$CDM model of cosmology. PBHs of masses between $10^{16}$ and $10^{16}$ g, in the so-called asteroid mass range, are currently unconstrained and can saturate the DM cosmological abundance. MeV emission from PBH in this mass range is expected to come from PBH evaporation, a mechanism predicted by Stephen Hawking. In this talk, I will present our search for the PBH signal with 16 years of SPI data, and demonstrate that PBHs cannot account for all the DM if their mass is smaller than $4\times10^{17}$ g.

Speaker: Joanna Berteaud (LAPTh, CNRS)

RICAP22_slides_Berteaud.pdf

14:50 Revisiting the Gamma-Ray Galactic Center Excess with Multi-Messenger Observations

The Galactic center excess (GCE) remains one of the most intriguing discoveries from the Fermi Large Area Telescope (LAT) observations. I will revisit characteristics of the GCE tested under an updated set of high-resolution galactic diffuse gamma-ray emission templates. This diffuse emission, which accounts for the bulk of the observed gamma rays, is ultimately due to cosmic-ray interactions with the interstellar medium. Using recent high-precision cosmic-ray observations, in addition to the continuing Fermi-LAT observations and observations from lower energy photons, we constrain the properties of the galactic diffuse emission. A large set of diffuse gamma-ray emission templates has been used which account for a very wide range of initial assumptions on the physical conditions in the inner galaxy. I will give an update on the spectral and morphological properties of the GCE and their physical implications. In particular, a high-energy tail is found at a higher significance than previously reported. This tail is very prominent in the northern hemisphere, and less so in the southern hemisphere. This strongly affects one prominent interpretation of the excess: known millisecond pulsars are incapable of producing this high-energy emission, even in the relatively softer southern hemisphere, and are therefore disfavored as the sole explanation of the GCE. The annihilation of dark matter particles of mass $40^{+10}_{-7}$ GeV (95$\%$ CL) to $b$ quarks with a cross-section of $\sigma v = 1.4^{+0.6}_{-0.3} \times 10^{-26}$ cm$^{3}$s$^{-1}$ provides a good fit to the excess especially in the relatively cleaner southern sky. Dark matter of the same mass range annihilating to $b$ quarks or heavier dark matter particles annihilating to heavier Standard Model bosons can combine with millisecond pulsars to provide a good fit to the southern hemisphere emission as well, as can a broken power-law spectrum which would be related to recent cosmic-ray burst activity.

Speaker: Dr Ilias Cholis (Oakland University)

RICAP_2022_Cholis.pdf

15:10 Dark matter indirect detection limits from complete annihilation pattern

Cosmological and astrophysical probes suggest that dark matter (DM) would make up for 85% of the total matter content of the Universe. However, the determination of its nature remains one of the greatest challenges of fundamental physics. Assuming the $\Lambda$CDM model, Weakly Interacting Massive Particles (WIMPs) would annihilate into Standard Model particles, such as $\gamma$ rays, which could be detected by ground-based telescopes. Dwarf spheroidal galaxies represent promising targets for such indirect searches as they are assumed to be highly dark matter dominated with the absence of astrophysical sources nearby. So far, previous studies have presented upper limits on the annihilation cross section $\langle \sigma v \rangle$ assuming single exclusive annihilation channels. In this work, we consider more realistic situation and take into account the complete annihilation pattern of the dark matter particle in order to study their impact on the derivation of the upper limits on the dark matter annihilation cross section.
We use mock data for the Cherenkov Telescope Array (CTA) simulating the observations of the promising dwarf spheroidal galaxy Sculptor. We show the impact of considering the full decay pattern within a phenomenologically viable particle physics model.

Speaker: Celine Armand (University of Geneva)

Impact_DM_model_Armand_Herrmann_RICAP.pdf

15:30 → 16:00 Coffe break

16:00 → 17:30 Extra-Galactic sources: - 2

Conveners: Dario Gasparrini (Istituto Nazionale di Fisica Nucleare), Elisa Prandini (University of Padova and INFN)

16:00 IXPE results for the extragalactic sky

X-ray polarization is a crucial probe of the magnetic field structure and emission processes in astrophysical systems. This is particularly true for active galactic nuclei (AGN). In radio-loud AGN, X-ray polarimetry allows us to investigate particle acceleration and composition in jets, while in radio-quiet AGN it allows us to look at matter under extreme conditions at the heart of the supermassive black hole. Until now, polarization observations have been limited to the radio-to-optical range, thereby leaving a gap in our knowledge of the processes and physical conditions in the most energetic objects. The recently launched Imaging X-ray Polarimetry Explorer -- IXPE, the first X-ray polarization mission to target AGN, thus offers a radically new way of studying high-energy processes. I will discuss results from the first year of IXPE observations of the extragalactic sky that clearly demonstrate the importance of X-ray polarization in our understanding of the Universe.

Speaker: Ioannis Liodakis (KIPAC, Stanford University)

16:20 Unravelling the complex behaviour of our closest very-high-energy gamma-ray blazars, Mrk421 and Mrk501, through decades-long multi-instrument observations

Owing to their proximity and their intense broadband emission from radio to very-high-energy gamma rays, Mrk421 and Mrk501 are among the blazars that can be studied with the greatest level of detail; and hence one can use them as a sort of astrophysical laboratories to study the blazar's phenomena. Because of that, these two objects have been the focus of multiple extensive multi-instrument campaigns during decades. In the conference I will show that, despite some differences in the variability patterns of these two sources, there are also a number of similarities that support a broadband emission dominated by leptonic scenarios, as well as indications for in situ electron acceleration in multiple compact regions. I will discuss the complexity in the temporal evolution of their broadband emission, the presence of different flavours of flaring activity, and highlight a few recent results. These multi-instrument observations on Mrk421 and Mrk501 have yielded thought-provoking results, and demonstrate the importance of performing a continuous monitoring over multi-year timescales to fully characterise the dynamics of blazars.

Speaker: David Paneque (Max Planck Institute for Physics)

Paneque_RICAP-2022_v3.pdf

16:40 ET and the perspectives of GW detection

After the groundbreaking first detection of Gravitational Waves by the LIGO/Virgo Collaborations, the design of the third generation of gravitation wave interferometric antennas has gained a substantial interest and momentum. The Cosmic Explorer in the US and the European Einstein Telescope are the instruments which will take the legacy of the current generation and further advance the reach of the GW antennas, both in terms of explored Universe and of type of accessible sources.
The talk will focus on the present status of the design of the Einstein Telescope, its technical challenges and the expected implications to the Gravitational Wave Astronomy progress.

Speaker: Antonino Chiummo (European Gravitational Observatory)

RICAP22-ET_status-chiummo_v1r0.pdf

16:00 → 17:30 Galactic Sources: - 2

Conveners: Alison Mitchell, Silvia Celli (Istituto Nazionale di Fisica Nucleare)

16:00 Unresolved sources naturally contribute to PeV $\gamma$-ray diffuse emission observed by Tibet AS$\gamma$

The Tibet AS$\gamma$ experiment provided the first measurement of the total diffuse gamma-ray emission from the Galactic disk in the sub-PeV energy range.
Based on analysis of the TeV sources included in the HGPS catalogue, we predict the expected contribution of unresolved pulsar-powered sources in the two angular windows of the Galactic plane observed by Tibet AS$\gamma$.
We show that the sum of this additional diffuse component due to unresolved sources and the truly diffuse emission, produced by the interaction of Cosmic Rays (CRs) with the interstellar medium, well saturates the Tibet data, without the need to introduce a progressive hardening of the cosmic-ray spectrum toward the Galactic centre.
We also investigate the typical age of these sources and we show that a relevant contribution is provided by relatively young PWNe with age ranging between $t\sim (7-33)$ kyr, depending on the sky region considered.
Finally, we estimate that CTA will be able to detect about $280$ ($140$) pulsar-powered sources in the whole Galaxy for a typical source size is $10$~pc ($40$~pc).

Speaker: Vittoria Vecchiotti

Vecchiotti_RICAP.pdf

16:18 Anisotropic diffusion cannot explain TeV halos

TeV halos have become a new class of astrophysical objects which were not predicted before their recent observation. They offer evidence that diffusion around sources (concretely, pulsars) is not compatible with the effective average diffusion that our models predict for the Galaxy. This directly impacts Galaxy formation, our knowledge of the propagation process throughout the Galaxy and our models of acceleration of charged particles by astrophysical sources like supernova remnants (SNRs) or Pulsar Wind Nebulae (PWN).
In this talk we show that, while anisotropic models may explain a unique source such as Geminga, the phase space of such solutions is very small and they are unable to simultaneously explain the size and approximate radial symmetry of the TeV halo population. Furthermore, we note that this conclusion holds for any CR-powered source (hadronic or leptonic), implying more generally that anisotropic diffusion does not dominate the propagation of particles near energetic sources (at least, below hundreds of TeV) because of the self-generated turbulence.

Speaker: Pedro De la Torre Luque (Oskar Klein Centre, Stockholm University)

16:36 X-ray detection of a nova in the fireball phase

Novae are caused by runaway thermonuclear burning in the hydrogen-rich envelopes of accreting white dwarfs, which leads to a rapid expansion of the envelope and the ejection of most of its mass. Theory has predicted the existence of a ‘fireball’ phase following directly on from the runaway fusion, which should be observable as a short, bright and soft X-ray flash before the nova becomes visible in the optical. I report of the discovery of this X-ray flash in the classical Galactic nova YZ Reticuli. The fireball phase happened 11 hours before the source's 9mag optical brightening. No X-ray source was detected 4h before and after the event, constraining the duration of the flash to shorter than 8h. In agreement with theoretical predictions, the source’s spectral shape is consistent with a black-body of 3.27×10^5 K (28.2 eV), or a white dwarf atmosphere, radiating at the Eddington luminosity, with a photosphere that is only slightly larger than a typical white dwarf. I discuss connections of novae to gamma and cosmic rays.

Speaker: Ole König

2022-09-06_YZRet_Flash_RICAP22_Rome.pdf

16:54 Revealing time-resolved hadronic particle acceleration in the recurrent nova RS Ophuichi with H.E.S.S.

Recurrent Novae (RNe) are known to experience multiple eruptions in the form of thermonuclear explosions, due to the accumulation of material accreted by a white dwarf from a binary companion star.
The well known RN RS Ophiuchi (RS Oph) underwent its latest eruption in 2021 and triggered numerous follow-up observations world wide, including with the High Energy Stereoscopic System (H.E.S.S.), an array of Imaging Atmospheric Cherenkov Telescopes.
Non-thermal emission up to TeV energies is observed coincident with the Nova eruption within the first days and up to a month after the optical peak, establishing novae as Galactic transients reaching TeV energies.
Analysis and interpretation of the data identifies time-resolved acceleration of cosmic-rays, constraining models of particle energisation.
Combining the data taken by H.E.S.S. with concurrent observations taken by the Fermi-LAT, a similar temporal profile is observed, favouring a common origin to the emission.
In this talk, the detection of the non-thermal VHE emission from the RN RS Oph by H.E.S.S. will be presented and plausible models for the VHE emission discussed.

Speaker: Alison Mitchell

RSOph_RICAP22_HESS.pdf

RSOph_RICAP22_HESS.pptx

17:12 Evidence of hadronic origin of the gamma-ray emission from the nova RS Oph by the MAGIC telescopes

RS Ophiuchi (RS Oph) is a symbiotic recurrent nova that shows eruptive events roughly every 15 years. On August 8th August 2021, RS Oph erupted with its latest outburst. This event was detected with a wide range of multi-wavelength (MWL) instruments from radio up to very-high-energy (VHE) gamma rays. The MAGIC telescopes followed up on optical and high-energy triggers and initiated an observation campaign from August 9th till September 1st. RS Oph is the first nova detected in the VHE gamma-ray energy range. Together with optical, high energy, and VHE emission detected by MAGIC, it is evident that RS Oph conclusively accelerates hadrons during its eruption. We report on the detection of VHE gamma rays at a significant level of 13.2σ during the first 4 days of RS Oph with the MAGIC telescope. More importantly, we will present the MWL modeling which reveals a hadronic origin of the gamma-ray emission in this 2021 eruption, and its further implications for Galactic cosmic-rays.

Speaker: David Green (Max Planck Institut für Physik)

RICAP_RS_Oph_DGreen_v3.pdf

16:00 → 17:30 Hardware and Software developments

Convener: Tommaso Chiarusi (Istituto Nazionale di Fisica Nucleare)

16:00 VIRGO and the gravitational interferometry

The Advanced Virgo detector is a long scale enhanced Michelson interferometer placed in Italy, close to Pisa, with the aim of detecting gravitational waves from astronomical sources.
The Advanced Virgo interferometer has detected, together with the LIGO interferometers located in USA, an impressive collection of gravitational waves emissions in the last observation runs O2 and O3. During the last observation run (O3), which lasted about one year of data taking from April 2019 to March 2020, were detected about 80 events of gravitational wave emissions.
After that the detector has been upgraded toward the Advanced Virgo + configuration, in order to enhance the sensitivity, and it is currently in the commissioning phase.
In this work, after an introduction on gravitational wave detection, will focus on the status of the Advanced Virgo + detector and the future upgrades which will further enhance the sensitivity toward unprecedented limits.

Speaker: Maddalena Mantovani (EGO)

RICAPP_v1.pptx

16:18 New measurements on an improved 3" Hamamatsu photomultiplier for the KM3NeT Neutrino Telescope

The KM3NeT experiment is a neutrino telescope which makes use of photomultiplier tubes to detect the Cherenkov radiation emitted by charged particles.
The first interaction of this light with the detector occurs at the photocathodes of the photomultiplier tubes, is then of primary importance to have the most complete characterization of these elements.
An improved version of the former R12199-02 model by Hamamatsu, named R14374-02, will be used until de completion of the experiment.
In this study we characterize one thousand of PMTs for the timing properties, dark rate and pulse response by using a dedicated apparatus.
We report the quantum efficiency response spectrum for two hundred elements and we compare it with the one provided at two wavelengths by the producer. This study will provide a statistically solid measurement of a quantity that is important and required for the numerical simulations of the detector response.

Speaker: Andreino Simonelli (INFN Napoli)

RICAP_simonelli.pdf

16:36 The multi-PMT optical module of KM3NeT

Presenter: Immacolata Carmen Rea (INFN) on behalf of KM3NeT Collaboration

Abtract:
For the first time in neutrino telescopes, the optical module of KM3NeT has 31 small photomultipliers instead of the traditional one large-dimension photomultiplier, as in other neutrino telescopes. Also, the size of the photocathode area in the module is unprecedented.
It is about the same as three 10-inch photomultipliers. The multi-PMT approach allows for a high resolution, good positioning and timing calibration. The integration of the optical
modules follows a strict protocol and a standardised procedure. It takes place in parallel at eight different integration sites in the labs of the collaboration. In this way, it is possible to reach a significant production rate of more than 100 well-qualified modules per month.
In this talk, we present details of the technology of the KM3NeT optical module and the integration process.

Speaker: Dr Immacolata Carmen Rea (Istituto Nazionale di Fisica Nucleare)

RICAP2022_ICRea_v4.pdf

16:54 The KM3NeT data acquisition system - Status and evolution

In this contribution, we present the DAQ system of the KM3NeT neutrino telescopes, ARCA, and ORCA, already operating while under construction, at the bottom of the Mediterranean Sea.
The system has to deal with a hardware-triggerless streaming readout of the optical modules in the telescopes. The throughput ranges from 20 Gbps up to hundreds of Gbps, scaling with the size of the detectors. The modularity of the DAQ architecture allowed for data taking since the first deployed sectors of the telescopes, which are currently under expansion. We will present the network infrastructure that connects the optical modules in the deep sea with the control station on-shore. It exploits frontier technologies like the Software Defined Networking and White Rabbit fabrics for handling complex connection topologies and distribution of the sub-nanosecond synchronisation. We will review the organisation of the control station with a focus on the exploitation of the Ansible and Docker technologies used to deploy and run the DAQ software. The implemented technology eases the integration of the online alert system, serving for instance the multi-messenger astronomy program of KM3NeT.

Speaker: Tommaso Chiarusi (Istituto Nazionale di Fisica Nucleare)

RICAP_2022_KM3NeT_DAQ_20220908_vfinal.pdf

17:12 Scalable solutions for the Control Unit of the KM3NeT DAQ system

The neutrino telescopes of KM3NeT are experiencing an exciting phase of quick growth, and will scale up the number of detection units of the current configuration by a factor between 10 and 25 in the coming years. In addition, the telescopes are becoming less homogeneous with new versions of optical modules running new versions of firmware and new instrumentation for calibration introduced in the originally repetitive lattice. The inner architecture and information flow of the Control Unit of the KM3NeT telescopes is described, along with qualitative and quantitative information and estimates concerning present and future computational and architectural complexity. The CPU, memory and network load will be shown to scale smoothly and slowly, not faster than O(N log N) where N is the number of detection units. The behaviour of the Control Unit will be shown in the case of temporary downgraded operation, as would happen in the case of failure of one or more computing machines. The flexible design and the roles of the Control Unit as an automatic load balancing system and hardware abstraction layer will show up naturally. The current goal is to control two full blocks of ARCA, i.e. 4370 CLBs and 128340 photomultipliers for 230 detection units, with a single mid-range commercial server machine. The option of a superscalar approach, with the control of the detector split among several dedicated servers, is also described along with its implementation details.

Speaker: Cristiano Bozza (Istituto Nazionale di Fisica Nucleare)

KM3NeT_CONF_2022_Talk_RICAP_ScalableSolutionsCU_Bozza_v4.pdf

17:30 → 18:15 Poster Session

17:30 Coffee Break

18:15 → 21:00 Visit to Museum

Info_dinner.pdf

21:00 → 23:30 Conference Dinner

Friday, 9 September

09:00 → 11:00 V Plenary Session chair Silvia Celli

09:00 Ultra-high energy cosmic rays with the Pierre Auger Observatory

In the era of the multi-messenger astronomy, ultra-high energy cosmic rays offer the unique opportunity to investigate the nature of astrophysical sources and of particle interactions in an energy range far beyond that covered by current particle accelerators.
The Pierre Auger Observatory, the world's largest cosmic ray detector, combines in a hybrid design the information from fluorescence telescopes, observing the longitudinal profile of extensive air showers, with a surface array, measuring the lateral distributions of secondary particles at the ground.
A review of selected results will be presented, focusing on the energy spectrum, nuclear mass composition measurements and search for neutral particles.
The future prospects will also be discussed in light of the extensive upgrade program being now implemented to further improve the potential of the Observatory.

Speaker: Lorenzo Perrone (Università del Salento and INFN Sezione di Lecce)

RICAP22_LPerrone.pdf

09:30 Last results from the AMS-02 experiment

The Alpha Magnetic Spectrometer (AMS-02) is a large acceptance magnetic spectrometer operating onboard the International Space Station since May 19th 2011 and is expected to operate in space until the end of the lifetime of the space station. AMS-02 so far detected more than 200 billion cosmic-ray events.
The detector's main goals are to search for antimatter and dark matter in space and the measurement of cosmic-ray composition and flux in the GeV to TeV range.
In this talk, I will present the latest results on cosmic-ray nuclei and antimatter particles.

Speaker: Manuela Vecchi

MVecchi_RICAP2022online.pdf

10:00 Latest results from the DAMPE space mission

The space-based DAMPE (DArk Matter Particle Explorer) particle detector has been taking data for more than 6 years since its successful launch in December 2015. Its main scientific goals include the indirect search of Dark Matter signatures in the cosmic lepton spectra, the study of Galactic Cosmic Rays up to energies of hundreds of TeV and studies on high-energy gamma ray astronomy. This talk will focus on Galactic Cosmic Rays and the measurement of their spectra, those being fundamental tools to investigate the mechanisms of acceleration at their sources and propagation through the interstellar medium. Results on proton and helium, which revealed new spectral features, will be reviewed. Ongoing analyses on the cosmic ray light component, medium and heavy mass mass nuclei will be discussed, together with studies of the so-called secondary cosmic rays.

Speaker: Ivan De Mitri (GSSI & INFN)

DeMitri-DAMPE-RICAP2022.pdf

10:30 Attaining the PeV frontier of the cosmic ray spectrum in space with HERD

The High Energy cosmic-Radiation Detection facility (HERD) is a calorimetric experiment planned to be launched in 2027. It will be operational for at least 10 years onboard the China’s Space Station. With HERD we will measure the energy spectrum of cosmic protons and heavier nuclei from 30 GeV to, for the first time in space, a few PeV. We will search for annihilation and decay products of dark matter both in the energy spectrum and anisotropy of electrons and positrons from 10 GeV to 100 TeV and in the energy spectrum of gamma rays, and we will survey the gamma-ray sky from 100 MeV. The five HERD subdetectors, the calorimeter (CALO), the scintillating fiber tracker (FIT), the plastic scintillator detector (PSD), the silicon charge detector (SCD) and the transition radiation detector (TRD), are currently under development. In this talk, I will present the science perspectives of HERD and its contribution to the multimessenger astronomy, as well as the performance of the subdetector prototypes assessed in several laboratory and beam tests.

Speaker: Chiara Perrina (EPFL)

ricap22_herd_cperrina.pdf

11:00 → 11:25 Coffee Break

11:25 → 13:30 VI Plenary Session chair Paolo Desiati

11:25 The Sun: an overview of its steady-state emission

The observed electromagnetic spectrum of the quiet Sun extends up to hundreds of GeVs. Indeed, the Sun is a recently-known gamma-ray source also in its quiescent state. The high-energy quiescent emission is supposed to originate from interactions of Galactic cosmic rays with the solar surface and its surroundings.

We provide an overview of our current knowledge on theoretical expectations and present observations of the steady-state emission from the Sun.

Speaker: Elena Orlando (Istituto Nazionale di Fisica Nucleare)

RICAP2022_Sun_Orlando.pdf

11:50 The AGILE experiment status and results

I will present the main recent AGILE results related to gravitational waves, neutrinos and the hunt for their electromagnetic counterparts, including some recent updates on the science of Fast Radio Burst (FRBs).
AGILE is an Italian Space Agency (ASI) space mission devoted to gamma-ray observations in the 30 MeV - 50 GeV energy range, with simultaneous X-ray imaging in the 18-60 keV band. Launched in April 2007, the AGILE satellite is operating nominally in its 16th year in orbit, and it is substantially contributing to improve our knowledge of the high-energy gamma-ray sky.
Gamma-ray emission from cosmic sources at energies above 100 MeV is intrinsically non-thermal, and the study of the wide variety of observed Galactic and Extragalactic gamma-ray sources provides a unique opportunity to test theories of particle acceleration and radiation processes in extreme conditions, and it may help to shed light on the foundations of physics itself.

Speaker: Carlotta Pittori (Istituto Nazionale di Fisica Nucleare)

AGILE_RICAP22_Pittori.pdf

12:15 The Fermi experiment status and results

The Fermi Gamma-ray Space Telescope was launched into Earth orbit in June, 2008. The Large Area Telescope is the principal instrument on board of Fermi satellite, it has revealed the high energy cosmos over more than 5 decades in energy (~30 MeV - 300 GeV), across more than ten decades in time scales (100 μs to years). With more than three billions photons from the whole sky and beyond 6,000 detected sources, Fermi-LAT observations have been crucial to improving our understanding of particle acceleration and gamma-ray production in astrophysical sources.

In this talk we highlight some of the scientific achievements of the last years and we look towards what the next years could reveal. In particular we will focused in the time-domain astrophysics in the multi-wavelength and multi-messenger context.

Speaker: Dr Sara Cutini (Istituto Nazionale di Fisica Nucleare)

Cutini_FermiHighlight_RICAP2022_v1.pdf

12:40 The Limadou project: status and results

The contribution aims at providing full comprehension of the impact that low-energy cosmic ray measurements performed by the Limadou collaboration have on our understanding and modelling of interstellar and interplanetary media, solar physics, space weather phenomena and ionosphere-magnetosphere coupling.
The Limadou project dates back to the early 2000s, when Italian and Chinese scientists started a collaboration to analyze the correlation of the seismic activity with phenomena observable with instruments placed in low-Earth orbit. They reached the first milestone of the project in February 2018, when the first CSES satellite was launched and put into operation, in the framework of a joint cooperation program between the Chinese and Italian Space Agencies. After commissioning, all payloads provided the scientific community with high-quality data concerning the electric and magnetic field, ionospheric plasma, x-rays, electrons, protons and nuclei. Finely binned time series are made publicly available for all these observational channels, allowing for a multi-messenger approach in the study of ionospheric perturbations.

Electrons and protons up to a few hundreds of MeV are measured with the High-Energy Particle Detector (HEPD), designed, constructed and operated by an Italian collaboration led by INFN. At the time of writing, the same group is assembling an upgraded version of the HEPD, to be hosted on the second satellite of the CSES constellation and placed in orbit by mid-2023.
I will briefly show figures for operational stability and in-flight performance of the HEPD onboard CSES-01. I will discuss the most important scientific results obtained so far, concerning time-dependent measurements of sub-GeV galactic cosmic rays, the estimation of trapped proton fluxes inside the South Atlantic Anomaly and the observation of geomagnetic storms.
Finally, I will describe the upgrade of HEPD for the CSES-02 satellite. I will show what makes it one of the most innovative space detectors for charged radiation, much more sensitive than its predecessor. I will discuss the scientific potential of multi-site measurements of high-energy particles trapped in both the inner and the outer Van Allen belts, reentrant electrons and protons, and cosmic rays as energetic as a few tens of MeV/nucleon.

Speaker: Roberto Iuppa (Istituto Nazionale di Fisica Nucleare)

iuppa_RICAP2022_CSESLimadou_20220909_v1.pdf

13:05 An Overview of Dark Matter Direct Detection

The search for dark matter is a leading mystery in astroparticle physics. With new detectors taking data and new technologies opening searches for a wider parameter space and theoretical models, the field is ever more sensitive to the potential of discovery. I'll provide an overview of the current state of the field, and point to anticipated advances in the next few years.

Speaker: Kimberly Palladino (University of Oxford)

Palladino WIMPs RICAP.pdf

13:30 → 14:30 Lunch Break

14:30 → 16:00 VII Plenary Session and Conference Summary

14:30 Remembering Tom Gaisser

Speakers: Elisa Resconi (Technical University of Munich), Paolo Lipari (Istituto Nazionale di Fisica Nucleare)

for-Tom.pdf

ricordo_tom.pdf

14:45 Remembering Benedetto D'Ettorre Piazzoli

Speakers: Rinaldo Santonico (ROMA2), Zhen Cao (to be confirmed) (Institute of High Energy Physics)

Remembering Benedetto.pptx

15:00 Best Posters prizes

Speaker: Antonio Capone (Istituto Nazionale di Fisica Nucleare)

Conference&posterprizes.pptx

15:15 Summary & Conclusions

Speaker: Aldo Morselli (Istituto Nazionale di Fisica Nucleare)

Morselli_Ricap22 r.pdf