Over the past four years, since April 2019, LHAASO has been in operation, either partially or as a whole. Utilizing the data collected, detection on Gamma-ray emissions from the Northern sky have been made, and observation results on various targets such as pulsar wind nebulae, pulsar halos, supernova remnants, Gamma-ray bursts, active galactic nuclei, and galactic diffused gamma rays, have...
Recent experimental results probe that UHECRs have extragalactic origin, and that their nature evolves towards heavier nuclear species with increasing energy. Several uncertainties however affect the understanding of the characteristics of UHECRs at Earth, as well as the association of UHECRs with possible source classes. In this talk I will report about the most recent experimental...
Over the past decade, AMS02 data have ushered us into a precision era for cosmic-ray physics. By unveiling features in the primary and secondary cosmic-ray spectra, these highly precise data challenge the current paradigms of galactic cosmic rays. In this talk, I will revisit the main results that have sparked interest within the cosmic-ray community, both about particles and antiparticles. I...
The intense star-forming activity typical of star-forming galaxies results in unique conditions for the acceleration of high-energy particles.
The enhanced supernova rate associated with such star formation can in fact transfer a large amount of power to non-thermal particles which,
in turn, can lose most of their energy in the dense and perturbed star-forming environment before being able...
IceCube collaboration has previously reported an evidence for neutrino signal from a Seyfert galaxy NGC 1068. This may suggest that all Seyfert galaxies emit neutrinos. To test this hypothesis, we identify the best candidate neutrino sources among nearby Seyfert galaxies, based on their hard X-ray properties. Only two other sources, NGC 4151 and NGC 3079 are expected to be detectable in 10...
The High Altitude Water Cherenkov (HAWC) observatory is highly suitable for large-scale survey work. The high duty time (95+%), large instantaneous FoV (2 sr), and sensitivity over the 300 GeV to more than 100 TeV energy range make it ideal for creating a catalog of very high energy (VHE) sources. Over the lifetime of the HAWC observatory, 4 catalogs have been produced 3 of which were...
Detection of gamma rays and cosmic rays from the annihilation or decay of dark matter particles is a promising method for identifying dark matter, understanding its intrinsic properties, and mapping its distribution in the universe. I will review rthe current status and discuss the prospects for indirect searches to robustly identify or exclude a dark matter signal using upcoming experiments...
IceCube's discovery of the astrophysical neutrino flux in the TeV-PeV range marked a crucial milestone in the development of high-energy neutrino astronomy. Recent searches identified the blazar TXS 0506+056 and the Seyfert Galaxy NGC 1068 as the first candidates for extragalactic neutrino emitters, standing out above the largely isotropic neutrino flux. While both objects are classified as...
In this contribution, we report the latest results of primary cosmic ray proton, helium, carbon, oxygen, neon, magnesium, silicon, sulfur, and iron fluxes based on the data collected by the Alpha Magnetic Spectrometer experiment on the International Space Station during 11 years of operation. We discuss the properties and composition of their spectra and present a novel model-independent...
We present high statistics measurements of the secondary cosmic rays Lithium, Beryllium, Boron, and Fluorine based on 11.5 years of AMS data. The properties of the secondary cosmic ray fluxes and their ratios to the primary cosmic rays Li/C, Be/C, B/C, Li/O, Be/O, B/O, and F/Si are discussed. The systematic comparison with the latest GALPROP cosmic ray model is presented.
IceCube has discovered a flux of astrophysical neutrinos and presented evidence for the first neutrino sources, a flaring blazar known as TXS 0506+056 and the active galaxy NGC 1068. However, the sources responsible for the majority of the astrophysical neutrino flux remain elusive. High-energy neutrinos can be produced when cosmic rays interact at their acceleration sites and during...
The Milky Way (MW) dwarf spheroidal satellite galaxies (dSphs) are particularly intriguing targets to search for gamma rays from dark matter (DM) annihilation or decay. They are nearby, DM-dominated, and lack significant emission from standard astrophysical processes. Previous studies using the Fermi Large Area Telescope (LAT) of DM-induced emission from dSphs provide some of the most...
The fourth release of the Fourth Catalog of Fermi-LAT Sources (4FGL-DR4), based on 14 years of data between 50 MeV and 1 TeV, is presented. Improvements in the analysis method relative to the original 4FGL catalog and new features are reviewed. The 4FGL-DR4 includes about 500 more sources than the previous release (4FGL-DR3, obtained with 12 years of data) and about 2100 more sources than...
We will report the latest results on the properties of nitrogen (N), sodium (Na), and aluminum (Al) cosmic rays in the rigidity range 2.15 GV to 3.0 TV based on 5 million N, 0.58 million Na and 0.64 million Al nuclei collected by the AMS. We observe all three fluxes are well described by the sums of a primary cosmic ray component and a secondary cosmic ray component. With our measurements, the...
The nature and characteristics of dark matter (DM) have long been a mystery in cosmology and astrophysics. Various DM theories propose that weakly interacting massive particles (WIMPs; mass ~ 1 TeV) can decay or annihilate into standard model particles, producing electromagnetic radiation, specifically very-high-energy (VHE) gamma rays exceeding 100 GeV. Additionally, ultra-heavy DM (mass >...
Lithium and Beryllium nuclei in cosmic rays are expected to be secondaries produced by the fragmentation of primary cosmic rays during their propagation in the Galaxy. Therefore, their fluxes contain essential information on cosmic ray propagation and sources. Secondary-to-primary flux ratios provide measurements of the material traversed by cosmic rays in their journey through the Galaxy. The...
The accretion flows around supermassive black holes would be a part of emission sources of the IceCube neutrinos. The effects of the global structure of the magnetized accretion flows on the neutrino SEDs are, however, still uncertain. We, therefore, carry out the calculation of SEDs of high energy neutrinos by using three dimensional general relativistic magnetohydrodynamic (GRMHD)...
The Crab pulsar (PSR J0534+2200), whilst being among the best studied objects in the sky, still challenges our understanding of the very-high-energy (VHE) emission processes in pulsars. Pulsed gamma rays are detected beyond 1 TeV, with a phase-folded lightcurve that presents two characteristic peaks joint by a "bridge". The trailing peak progressively becomes more dominant as energy increases...
We present the precision measurements of eleven years of the cosmic-ray positrons flux in the energy range from 0.5 GeV to 1.4 TeV based on 3.9 million positrons collected by the Alpha Magnetic Spectrometer on the International Space Station. The positron flux measured by the AMS exhibits complex and unexpected energy dependence. Its distinctive properties are: a significant excess starting...
Over the past decade, a significant number of supernovae exhibiting luminosities that exceed $10^{43}\,\mathrm{erg\, s^{-1}}$ and characterized by narrow hydrogen lines in their spectra have been discovered. These supernovae are believed to be powered by the collision of ejected material with a dense circumstellar medium (CSM). The interaction of the SNe ejecta with the CSM results in a shock...
The next generation ground-based instrument for very-high-energy gamma-ray observations will be the Cherenkov Telescope Array Observatory (CTAO). At one of the two planned sites, La Palma (Canary Islands, Spain), the first prototype of a Large-Sized Telescope, LST-1, is already operational and is currently under commissioning. The two MAGIC Cherenkov telescopes have been operating in...
Dwarf spheroidal galaxies (dSphs) are among the most dark matter (DM) dominated objects, with negligible expected astrophysical gamma-ray emission. This makes nearby dSphs ideal targets for indirect searches of a DM particle signal. The accurate knowledge of their DM content makes it possible to derive robust constraints on the velocity-weighted cross section of DM annihilation. We report on a...
Deuterons are the most abundant secondary nuclei in cosmic rays and precise measurement of their properties will allow to test and constrain various cosmic ray propagation models.
The precision measurement of deuteron flux with kinetic energy per nucleon from 0.2 GeV/n to 9 GeV/n based on 15 million deuterons collected by Alpha Magnetic Spectrometer during the first 10 years of operation on...
The Crab pulsar wind nebula is one of the best-studied objects in the gamma-ray sky. Recently, its angular extension in the gamma-ray domain could be resolved in separate analyses of Fermi-LAT and H.E.S.S. data, which provides crucial information about the spatial distribution of relativistic particles in the nebula. In this contribution we provide, for the first time, a measurement of the...
Observations of very high-energy (>1 TeV) cosmic gamma rays are a powerful, unique tool to explore new physics beyond the Standard Model. The Southern Wide-field Gamma-Ray Observatory (SWGO), a next-generation experiment looking for cosmic gamma rays, will be situated in the Southern hemisphere with gamma-ray sensitivity up to the PeV range. This observatory will have an order of magnitude...
The ultra-high energy cosmic neutrinos, which usually perambulate gargantuan scales in the extragalactic universe, are expected to play a crucial role in determining the origin of cosmic rays as well as probing new physics extending even up to the Planck scale. This epitomizes the selling point of several currently running or planned neutrino telescopes. If neutrinos have magnetic moment owing...
We present the latest precision measurements of the electron flux based on 57 million electron events collected by the Alpha Magnetic Spectrometer on the International Space Station during first eleven years of operations. These results on cosmic-ray electrons in the energy range from 0.5 GeV to 2 TeV reveal new features that are crucial for providing insights into their origins. Comparing the...
Latest results by AMS on the fluxes and flux ratios of charged elementary particles in the absolute rigidity range from 1 up to 2000 GV reveal unique properties of cosmic charged elementary particles. In the absolute rigidity range ~60 to ~500 GV, the antiproton flux and proton flux have nearly identical rigidity dependence. This behavior indicates an excess of high energy antiprotons compared...
Absorption and emission lines in the optical spectrum are typically used to investigate the presence of large-scale environments in active galactic nuclei (AGNs). BL Lac objects - which are a category of AGNs with the relativistic jet pointing directly to the observer - are supposed to represent a late evolution stage of AGNs. Their large-scale structures are probably poorer of material, which...
One of the most elusive unknowns in particle physics and astrophysics today is the fundamental nature of dark matter. It is theoretically well-motivated that dark matter is a weakly interacting massive particle (WIMP) -- a particle lying within the GeV to TeV energy ranges that interacts very weakly with Standard Model particles. Such behavior makes dark matter extremely difficult to detect...
Reverberation starts when the PWN is reached by the reverse shock of the supernova remnant. Depending on the internal to the outer pressure balance, it might induce a compression of the PWN. This period has a large (even huge) effect on the subsequent dynamical and spectral evolution.
In this talk, we shall present numerical evidence for that the shell accumulated at the PWN boundary is far...
Cosmic-ray electrons and positrons (CREs) of TeV energies suffer severe energy losses during their propagation limiting their traveling distances to just a few kpc and, therefore, their measurement provides a unique channel to constrain local Galactic cosmic-ray sources. However, at high energies their detection is intrinsically difficult due to their low abundances and steep spectrum. In this...
Resolving the origin of diffuse TeV-PeV neutrino emission measured by the IceCube Observatory is a key part of multi-messenger astronomy. We study the neutrino emission of Galactic and extragalactic source populations by investigating the relation between IceCube's point-source discovery potential and diffuse flux observations. For Galactic sources, we show that the flux of unresolved neutrino...
The luminous pulsar wind nebula (PWN) HESS J1825-137 was the first object in gamma-ray astronomy that was discovered to have energy-dependent morphology. In addition to its detection and this discovery by H.E.S.S., J1825-137 and the region around it have been explored and characterized also using the VERITAS, Fermi-LAT, HAWC, and LHAASO instruments. Its exceptional TeV luminosity has been...
The X-ray and $\gamma$-ray emission of globular clusters (GCs) is attributed to their large fraction of compact binary systems, especially those with millisecond pulsars (MSPs). We analyze a population of 124 Galactic GCs to investigate how their dynamical properties affect the formation and evolution of compact binary systems and how this can be translated into the clusters' observed X-ray...
The DArk Matter Particle Explorer (DAMPE) is a satellite-borne experiment, in operation since 2015, aimed at studying high-energy gamma rays and cosmic rays. Proton and helium are the first- and second-most abundant components in cosmic rays. Given their smaller interaction cross-sections with the interstellar medium, compared to heavier nuclei, they can travel larger distances, thereby...
It is well known that our Universe is opaque to high-energy gamma-rays due to electromagnetic cascades over cosmological distances, resulting in a spectrum of secondary gamma-rays at lower energies. In this talk, we will summarize the physics and features of such cascades and discuss their importance in the context of multimessenger astrophysics up to ultra-high energies. In particular, we...
W44 is a middle-aged Supernova Remnant (SNR) largely investigated to probe acceleration of Cosmic Rays (CRs). Previous studies already showed the presence of gamma-ray emission not only from the remnant, but also from its surroundings, thought to be due to high-energy CRs escaping from the forward shock of the remnant.
We present a detailed morphological and spectral analysis of Fermi-LAT...
Dark Matter (DM) existence is a milestone of the cosmological standard model and, yet, its discovery still remains a complete conundrum. In this contribution, we investigate a unique and original way to probe properties of light-particle dark matter candidates, exploiting the nature of the cosmic-ray (CR) transport inside starburst nuclei (SBNs). Indeed, SBNs are considered CR reservoirs,...
The quiet Sun, i.e., in its nonflaring state or nonflaring regions, emits thermal radiation from radio to ultraviolet. The quiet Sun also produces nonthermal radiation observed in gamma rays due to interactions of Galactic cosmic rays (GCRs) with the solar atmosphere and photons. We report on a new component: the synchrotron emission by GCR electrons in the solar magnetic field. To the best of...
Primordial Black Holes (PBHs) may exist and constitute a portion of the Dark Matter. Their discovery would have profound consequences on fundamental physics and possibly solve some outstanding puzzles in cosmology, such as the existence of high-redshift supermassive black holes.
Baryonic matter would be inevitably attracted towards these objects and form structures such as accretion disks,...
The Pacific Ocean Neutrino Experiment is a new neutrino telescope in the Pacific Ocean that is planned to consist of at least 70 instrumented mooring lines and span more than one cubic kilometre. Using the existing underwater infrastructure of Ocean Networks Canada, P-ONE aims to detect neutrinos with energies ranging from TeV to PeV, and will complement the sky coverage of both IceCube and...
Galactic pulsars, such as Geminga, are surrounded by a bright and extended TeV emission. This radiation is compatible with multi-TeV electrons scattering off low-energy photons via the inverse-Compton scattering process. To date, about 10 TeV halos have been observed around known pulsars. Next-generation gamma-ray detectors, such the Cherenkov Telescope Array (CTA), will have unprecedented...
The STRings for Absorption length in Water (STRAW) and its successor STRAW-b are the pathfinders for the future Pacific Ocean Neutrino Experiment (P-ONE). Both experiments are mooring lines instrumented with several light emitter and receiver modules. The goals of the pathfinders are to measure the water's attenuation length of water, characterize the background light spectrum and perform...
The China Seismo-Electromagnetic Satellite (CSES) project is composed of a series of Italian-Chinese space missions, dedicated to monitoring the near-Earth environment. The High-Energy Particle Detectors (HEPD-02) is one of the scientific instruments aboard the second satellite of the CSES mission, CSES-02, which is expected to be put into sun-synchronous orbit in early 2024.
The HEPD-02...
This contribution presents our approach to identify potential exotic objects in the gamma-ray sky using the Fermi-LAT 4FGL-DR3 catalog. We employ both supervised and unsupervised classification techniques to analyze the gamma-ray spectra of sources in the catalog.
For the supervised approach, we simulate realistic gamma-ray spectra and utilize them to train a classifier specifically designed...
Observations by the HAWC and HESS telescopes have found extended TeV emission consistent with a handful of young and middle-aged pulsars. In this talk, I will show that these detections have significant implications for our understanding of both pulsar emission and TeV astrophysics. Most importantly, the high-luminosity and spatial extension of TeV halos indicate that cosmic-ray diffusion on...
The 𝛾-ray emission from stars is induced by the interaction of cosmic rays with stellar atmospheres and photon fields. This emission is expected to come in two main components: a stellar disk emission, where 𝛾-rays are mainly produced in atmospheric showers generated by hadronic cosmic rays, and an extended halo emission, where the high density of soft photons in the surroundings of stars...
A key strategy for constraining the properties of particle dark matter is the search for the gamma-rays produced by its annihilation or decay in dwarf spheroidal galaxies. The Model-Agnostic Dark Halo Analysis Tool (MADHAT) is a publicly-available computational tool that uses data from the Fermi-LAT to constrain gamma ray emission from dwarf satellite galaxies and dwarf galaxy candidates due...
The High Energy Particle Detector 01 (HEPD-01) is hosted on board of the China Seismo-Electromagnetic Satellite (CSES-01). It was launched on the 2nd of February 2018 and it is on a Sun-Synchronous orbit at an altitude of 500 km. HEPD-01 is completely developed by the Italian part of the CSES-Limadou collaboration. It is dedicated to the detection of charged particles: electrons (about 3-100...
On behalf of the KM3NeT Collaboration.
Strong star-forming activity in astrophysical environments leads to an enhancement of hadronic gamma-ray and neutrino emissions. In this contribution, we explore the capability of the full KM3NeT/ARCA detector to trace TeVs neutrinos from star-forming environments, encompassing both diffuse and point-like signals. For the diffuse analysis,
we compute...
Although supernova remnants are thought to be responsible for the bulk of the flux of cosmic rays in our Galaxy, their ability to produce the highest-energy Galactic cosmic rays is challenged by observations. Measurements of TeV gamma rays from several supernova remnants suggest cut-offs in the underlying particle spectra significantly below PeV energies. On theoretical grounds, young massive...
The detection of MeV-GeV neutrinos from astronomical sources is a long-lasting challenge for neutrino experiments. The low flux predicted for transient sources, such as solar flares, would require a detector with both a large instrumented volume as well as a high density of photomultipliers (PMTs) to resolve the low-energy signature. We discuss how KM3NeT can play a key role in the search for...
The General Antiparticle Spectrometer (GAPS) is an upcoming Antarctic balloon mission to search for dark matter by measuring low-energy cosmic-ray antinuclei using a novel detection technique. GAPS is the first experiment optimized to detect cosmic-ray antideuterons below 0.25 GeV/n. Antideuteron production in this energy range is kinematically suppressed in standard astrophysical processes...
In this talk, I will present updated constraints on 'light' dark matter (DM) particles with masses between 1 MeV and 5 GeV. In this range, we can expect DM-produced $e^\pm$ pairs to upscatter ambient photons in the Milky Way via Inverse Compton, and produce a flux of X-rays that can be probed by a range of space observatories. Using diffuse X-ray data from XMM-Newton, INTEGRAL, NuSTAR and...
I present the results of cosmic ray interaction models applied to an unprecedentedly large sample of blazar AGN. The modeling was performed using an efficient, self-consistent and time-dependent numerical framework newly published as open-source software. I show that for a large number of sources, the X-ray and very-high-energy gamma-ray fluxes can be explained by cascades triggered by cosmic...
Dark matter is one of the ingredients of the standard cosmological model although we do not know its fundamental nature. Huge effort has been made in order to perform a direct detection of this dark matter component but up to now we have only seen it interacting gravitationally. In this regard the indirect detection is a promising method to search for dark matter, where we try to look at...
In the last decades, several young massive star clusters (YMSC) have been associated with extended $\gamma$-ray sources, suggesting that some acceleration process, able to produce particles at least up to hundreds of TeV, is at work. The number of YMSCs exhibiting $\gamma$-ray emission is around ten, while the possible sources amount to a significantly higher number, potentially reaching...
Upcoming neutrino telescopes will have an unprecedented sensitivity to ultra-high-energy (UHE) neutrinos, above 10 PeV. This achievement will allow to test physics beyond the Standard Model at a very high energy scale, including the decay of heavy dark matter particles. Previous works acknowledged this possibility, showing that the total number of detected events will allow to set competitive...
Novae have been recently established as prompt gamma-ray sources in the GeV energies, and also in one case in the TeV energies (RS Oph), lasting for a few days up to a month after the nova optical outburst. We consider a scenario in which electrons, accelerated continuously in the expending nova shell, escape into the surrounding medium forming an extended nebula around recurrent nova....
The detection of cosmic gamma rays, high-energy neutrinos and cosmic rays (CRs) signal the existence of environments in the Universe that allow particle acceleration to extremely high energies. These observable signatures from putative CR sources are the result of in-source acceleration of particles, their energy and time-dependent transport including interactions in an evolving environment...
Monopoles are inevitable predictions of GUT theories. They are produced during phase transitions in the early universe, but also mechanisms like Schwinger effect in strong magnetic fields could give relevant contributions to the monopole number density. I will show that from the detection of intergalactic magnetic fields we can infer additional bounds on the magnetic monopole flux. I will also...
Gamma-ray observation in the sub-PeV range provides a method of investigating accelerators of the Galactic PeV cosmic rays, so-called PeVatrons. However, the detection of PeVatrons has not been established yet, and a large fraction of sub-PeV gamma-ray sources still has an unknown origin, which requires detailed studies for individual gamma-ray sources. A TeV gamma-ray source HESS J1843-033 is...
The detection of high-energy astrophysical neutrinos by IceCube has opened a new window on our Universe. While IceCube has measured the flux of these neutrinos at energies up to several PeV, much remains to be discovered regarding their origin and nature. Currently, measurements are limited by the small sample size of astrophysical neutrinos and by the difficulty of discriminating between...
The Galactic Center is one of the most studied regions of the sky. Of particular interest is the supermassive black hole Sagittarius A*, whose proximity provides an opportunity for morphological investigations into the acceleration of cosmic rays in an extreme environment. Previous observations with very-high-energy gamma rays, in particular the detection of a diffuse emission component on a...
Hot white dwarfs lose energy mainly in the form of neutrinos through plasmon decay from the inner part of the star. Dark sectors, which are being studied to explain a broad collection of anomalies and unknown physics, do have an impact in the energy lost by this mechanism. I will focus on a Three Portal model that connects dark sectors to the Standard Model through a dark scalar (Higgs), a...
I will discuss the current status of various dark matter indirect probes, some recent new developments, and possible new directions in the future.
I will review the Primordial Black Hole (PBH) hypothesis for explaining the dark matter in the universe. I will focus on the peculiar ‘asteroid mass range’ where this possibility remains viable, discussing a number of signatures that have been proposed to search for them, and present current constraints. I will conclude highlighting some perspectives for the foreseeable future.
Strong lensing provides a direct, purely gravitational method to infer the abundance and internal structure of dark matter halos, which in turn depend on the particle nature of dark matter. Follow up of quadruple image strong lens systems with JWST will deliver more precise and constraining measurements than currently possible with HST, leading to unprecedented constraints on the nature of...
In this talk I will focus on a promising novel line of research for dark matter indirect detection, called the cross-correlation technique. This novel technique aims to correlate two distinctive features of DM: on one side, an electromagnetic signal, which is a manifestation of the particle nature of DM and, on the other side, a gravitational tracer of the DM distribution in the Universe. A...
Multimessenger observations leverage the unique roles of each messenger to provide new insight into our universe. With successive upgrades to current facilities and the launch of new instruments, and hence a growing number of detections, we are prepared to address a number of fundamental questions in cosmology. In this talk, I will give an overview of the exciting opportunities that...
Dwarf galaxies are the lowest mass galaxies in the Universe but they are key laboratories for understanding galaxy formation processes, since their properties are sensitive to how these processes are in play. Moreover they are strong probes for cosmology and dark matter properties. There are long standing debates in the literature on whether the observed properties of dwarf galaxies are...
The Fuzzy Dark Matter (FDM) model predicts that dark matter is composed of ultralight scalar field particles which possess macroscopic de Broglie wavelengths in the kpc scale. The wave behaviour of FDM erases structure formation on small scales and leads to the formation of galactic cores or solitons. This has been a subject of great interest in addressing challenges of the ΛCDM model, where...
The question of whether there is new physics beyond our current standard model, Lambda Cold Dark Matter (LCDM), is a crucial unresolved issue in cosmology today. Recent measurements of the Hubble constant (Ho) using Cepheids and Type Ia supernovae (SNe) appear to differ significantly (5-sigma) from values inferred from the cosmic microwave background (CMB) fluctuations. This discrepancy, if...
The creation of anti-nuclei in the Galaxy has been has been discussed as a possible signal of exotic production mechanisms such as primordial black hole evaporation or dark matter decay/annihilation, in addition to the conventional production from cosmic-ray (CR) interactions. Tentative observations of CR antihelium by the AMS-02 collaboration have re-energized the quest to use antinuclei to...
Supernova Remnants (SNRs) are the primary suspect among Galactic sources to accelerate particles via diffusive shock acceleration up to the necessary PeV energies.The gamma-ray emission of SNRs can provide direct evidence of leptonic (inverse Compton and bremsstrahlung) and hadronic (pion-decay from proton-proton interactions) processes.
Puppis A is a middle-aged SNR interacting with...
IceCube has reported evidence for neutrino emission from the nearby active galaxy NGC 1068 and the gamma-ray blazar TXS 0506+056. A search for electromagnetic radiation temporally and spatially-correlated with high-energy IceCube neutrino events is an important strategy for exploring the connection between neutrinos and high-energy blazars. Here we report on the very-high-energy gamma-ray and...
Cosmic-ray antiprotons from AMS-02 offer valuable information about the nature of dark matter, but their interpretation is complicated by large uncertainties in the modeling of cosmic ray propagation. In this talk, I intend to present a novel framework to efficiently marginalize over various uncertainties in order to obtain robust AMS-02 likelihoods for arbitrary dark matter models. The three...
A new supernova remnant (SNR) was recently detected at radio frequencies with ASKAP at (l, b) = (288.8, -6.3) by Filipovic et al. 2023 (submitted), partly coincident with a Fermi-LAT extended source that was provisionally associated with a molecular cloud. We reanalysed the region around the SNR using Fermipy, taking 14.5 years of data in a ROI of 12°.
Extended emission from the region was...
The search for gamma ray counterparts of IceCube neutrino events is crucial for understanding the role of blazars as possible sources of cosmic neutrinos. We have searched the counterparts for IceCube neutrinos events in the AGILE gamma-ray satellite public archive in the interval 2018-2020.
We present the candidate sources in the regions centered on the detected neutrinos and their light...
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...
The cosmic-ray experiment AMS-02 has reported the possible detection of $\sim 10$ anti-helium events. Conventional production mechanisms struggle to explain the similar fluxes observed for both isotopes ${}^4\overline{\text{He}}$ and ${}^3\overline{\text{He}}$. In this talk, I discuss how these species could be created through "anti-nucleosynthesis" occurring in fireballs of standard model...
A remarkable detection was recently made when a high-energy neutrino event detected by IceCube was linked to the Fermi-LAT detected blazar TXS 0506+056. However, our knowledge of observable neutrino-emitting blazars is limited, hindering future investigations. To address this issue, we combine a physically motivated model with three key free parameters capable of producing both...
The region corresponding to the Centaurus Galactic spiral arm tangent of our galaxy, within 1 deg radius around Galactic longitude 312º, harbours a rich environment with candidate sources for gamma-ray astronomy. In particular, it contains five pulsars, with spin-down powers ranging between 10^35 and 10^37 erg.s−1, and characteristic ages between 13.6 and 62.8 kyr. The possible presence of...
Primordial magnetic fields (PMFs) can enhance baryon perturbations on scales below the photon mean free path. However, a magnetically driven baryon fluid becomes turbulent near recombination, thereby damping out baryon perturbations below the turbulence scale. In this letter, we show that the growth of baryon perturbations is gravitationally imprinted in the dark matter perturbations, which...
Neutron stars (NSs) are promising cosmic laboratories to test the nature of dark matter (DM). DM captured by the strong gravitational field of these stellar remnants transfers kinetic energy to the star during the collision. This can produce anomalous heating of old neutron stars. Further thermalization and DM annihilation can add an extra source of heating. We improve former calculations of...
In the last decade, the IceCube South Pole Neutrino Observatory has observed an astrophysical neutrino flux with unexpected implications for the environments of extragalactic accelerators. The discovery of the high-energy, transient neutrino source TXS 0506+056 has drawn further attention to blazars, and the traditional correlation of their activity with gamma-ray emission. However, gamma-ray...
Among mechanisms for generating the baryon asymmetry of the universe, leptogenesis is attractive since it simultaneously explains the small neutrino masses via the seesaw mechanism. Experiments offer some valuable constraints, but the parameter space of even minimal leptogenesis models are high-dimensional and difficult to probe directly. However considering a simple and well studied...
Heavy inelastic dark matter can substantially annihilate outside neutron stars for inelastic inter-state mass splittings $\sim$MeV and produce standard model particles. Such inelastic dark matter annihilations can happen during the long timescale of the dark matter thermalization, i.e. losing enough kinetic energy to enter an orbit fully contained inside the neutron star. In this talk, I will...
The SNR G106.3+2.7, with its associated molecular cloud complex, is one of the candidate TeV counterparts of LHAASO J2226+6057, one of the 12 LHAASO Galactic Pevatrons. The other candidate is the Boomerang PWN, associated with the PSR J2229+6114. Different gamma-ray facilities have detected this VHE region with an elongated morphology: the SNR is located in the "tail" of the VHE emission and...
Recent observations are shedding light on the important role that active galactic nuclei (AGNs) play in the production of high-energy neutrinos. Despite the growing evidence that blazars are good candidates to be neutrino emitters, our understanding of the physical processes and locations of production remains limited.
In this contribution we present the study of one promising object, 5BZB...
Neutron stars can host strong electromagnetic fields deep in their magnetospheres capable of sourcing axions. Low mass axions are produced relativistically and can resonantly convert into radio photons as they escape the magnetosphere. For heavier axions an increasing fraction will instead end up populating a cloud of bound states around the parent neutron star. In this talk I will discuss the...
The recent detection of 12 gamma-ray Galactic sources well above $E>100$ TeV by the LHAASO observatory has been a breakthrough in the context of Cosmic Ray (CR) origin search.
Although most of these sources are unidentified, they are often spatially correlated with leptonic accelerators, like pulsar and pulsar wind nebulae (PWNe). This dramatically affects the paradigm for which a gamma-ray...
We study the imprints of high-scale non-thermal leptogenesis on cosmic microwave background (CMB) from the measurements of the inflationary spectral index ($n_s$) and tensor-to-scalar ratio ($r$), which otherwise is inaccessible to the conventional laboratory experiments. We argue that non-thermal production of baryon (lepton) asymmetry from subsequent decays of inflaton to heavy right-handed...
The IceCube telescope found an excess of 79 neutrinos
at Tera-electron-volt energies correlated with the galaxy NCG1068 (the corresponding significance is 4.2 sigmas), making this Seyfert galaxy spatially coincident with the
hottest spot in the northern high-energy neutrino sky.
Considering that NGC1068 presents a core with a high star-formation rate and hosts an active galactic nucleus,...
Axion-like particles (ALPs) are a well-motivated candidate for constituting a significant fraction of dark matter in the Universe. They are produced in high-energy environments of core-collapse supernovae (CCSNe) or binary neutron star (BNS) mergers via Primakoff process. As they enter the Milky Way's magnetic field, ALPs could undergo conversion into gamma rays, resulting in a characteristic...
The detection of 14 ultra-high-energy (UHE, photon energy above 100 TeV) gamma-ray sources by LHAASO has opened up new avenues for investigating Galactic PeVatrons. We present the status of a VERITAS study of three intriguing LHAASO sources: J2108+5157, J0341+5158, and J0621+3755. J2108+5157 and J0341+5158 are "dark PeVatrons" without any source association. J0621+3755 is a TeV halo candidate...
We propose a novel mechanism to generate sterile neutrinos $\nu_s$ in the early Universe, by converting ordinary neutrinos $\nu_\alpha$ in scattering processes $\nu_s \nu_\alpha \to \nu_s \nu_s$. After initial production by oscillations, this leads to an exponential growth in the sterile neutrino abundance. We show that such a production regime naturally occurs for self-interacting sterile...
Axion-like particles (ALPs) are a class of pseudo-Nambu-Goldstone bosons that have been proposed as potential candidates for dark matter. When propagating through astronomical environments embedded with magnetic fields, very high-energy gamma rays can convert to ALPs, modifying the spectral energy distribution of the observed target. Our study employs around 40 hours of data from the MAGIC...
Gamma-Ray Bursts (GRBs) are among the brightest and most energetic events in the Universe, in the form of violent extragalactic explosions of gamma rays, which are detected at the top of the Earth’s atmosphere by high-energy photon detectors. Although not specifically designed for gamma-ray detection, the High-Energy Particle Detector (HEPD-01), operational since 2018 on a low-Earth orbit,...
According to the observations up to date, there is more flux in cosmic neutrinos at lower energies (<100 TeV) than that could be expected from gamma rays, if they have the same sources. The diffuse gamma-ray sky observed by the Fermi Gamma-ray Space Telescope is dominated by blazars (~80%), while recent studies suggest blazars might be only subdominant sources of the diffuse high-energy...
The detection of GRBs at very high energy (> 100 GeV) was a long-awaited result, and many observations by multiple instruments were needed before achieving this goal. The study presented here for the first time is based on a complete re-analysis of 15 years of H.E.S.S. GRBs observations, aiming to understand the reasons behind the previous lack of detections.
Through the utilisation of...
In this talk, I will discuss the freeze-in production of Feebly Interacting Massive Particle (FIMP) dark matter candidates through a neutrino portal, in the case where an early matter-dominated era took place for some period between inflation and Big Bang Nucleosynthesis. In this model, we consider a hidden sector comprised of a fermion and a complex scalar, with the lightest one regarded as a...
In the hunt for new physics phenomena, such as dark matter, it is
crucial to compare experimental data to theoretical models. During this
step, the most likely values of the model’s parameters — such as particle
masses and cross sections — are inferred. However, a rigorous statistical
treatment of such an inference is oftentimes not practically feasible with-
out making significant...
In this talk, I will analyse the effect on the supernova neutrino flux duration of the resonant production of low-mass vector mediators from neutrino-antineutrino coalescence in the core of proto-neutron stars. First, I will argue that, in the regime where neutrino-antineutrino interactions via the new vector mediator dominate over the Standard Model neutrino-nucleon scattering, a...
High-energy gamma rays are extremely important for the interpretation of explosive cosmic events related to the formation of neutron stars and black holes. The long-duration gamma-ray burst GRB 221009A was a recent powerful event that - with its remarkable intensity, spectral features, and duration - was clearly detected also by the AGILE satellite in the MeV-GeV energy range. Through its...
Ever since the discovery of neutrinos, we have wondered if neutrinos are their own antiparticles, and whether lepton number is violated or not. One remarkable possibility is that lepton-number violation in the Standard Model is soft. In such scenarios, neutrinos have a pseudo-Dirac nature, with a tiny mass difference between active and sterile states, having oscillations driven by this tiny...
TeV blazars dominate the extragalactic gamma-ray sky and highly energetic pair beams arising from such blazar jets underproduce gamma rays in the GeV band while inverse-Compton scattering off the cosmic microwave background. Isotropic gamma ray background measurements strongly suggest that when the intergalactic magnetic field is feeble, space plasma instabilities can play a crucial role in...
We study single-field slow-roll inflation embedded in a Palatini quadratic $F(R)$ gravity, where the Einstein--Hilbert term has the wrong sign, apparently leading to repulsive gravity. This can be avoided as long as $F'(R)$ and $F''(R)$ stay positive. Surprisingly, consistency of the theory requires the Jordan frame inflaton potential to be unbounded from below. Even more surprisingly, this...
Neutrino flavor oscillation is a widely studied physical phenomena with far reaching consequences in understanding the standard model of particle physics and to search for physics beyond it. Oscillation arises because of mixing of the mass states in flavor states, and their evolution over time. It is an inherent quantum system for which flavor transitions are traditionally studied with...
Coherently oscillating axion clumps can in an external magnetic field emit electromagnetic radiation which causes them to decay. In the presence of plasma, such radiation can become resonant if the clump frequency matches the plasma frequency. In this talk, I discuss how backreaction affects the clump frequency over time enabling clumps with a range of different initial frequencies to become...
Starting from the first unequivocal detection of very high energy (VHE) emission from the luminous gamma-ray burst (GRB) GRB 190114C by the MAGIC telescopes, five detections of VHE emission from GRBs by ground-based instruments were reported as of today. Such new energetic components have become a new probe to explore GRB physics. GRB 201015A was a long GRB detected by the Swift/BAT and we...
We investigate the impact of stochastic quantum noise due to trans--Planckian effects on the primordial power spectrum for gravity waves during inflation. Given an energy scale Lambda, expected to be close to the Planck scale m_Pl and larger than the Hubble scale H, this noise is described in terms of a source term in the evolution equation for comoving modes k which changes its amplitude...
Photon-ALP oscillation results in the survival of gamma-rays from distant sources above TeV energies. Studies of CAST, Fermi-LAT, and IACT observed events that constrain the ALP parameters. We investigate the effect of photon-ALP oscillations on the gamma-ray spectra of the first extragalactic neutrino source, TXS 0506+056, for the observations of Fermi-LAT and MAGIC around the IC170922-A...
The Cryogenic Underground Observatory for Rare Events (CUORE) is the first bolometric experiment searching for $0\nu\beta\beta$ decay that has successfully reached the one-tonne mass scale. The detector, located at the Laboratori Nazionali del Gran Sasso (LNGS) in Italy, consists of an array of 988 TeO$_2$ crystals arranged in a compact cylindrical structure of 19 towers. CUORE began its first...
In gamma-ray bursts, X-ray afterglows frequently show a shallow decaying emission in their first few thousand seconds. Possible models for the shallow decay phase are continuous energy injection, late catch-up of lately launched ejecta, the evolution of microscopic parameters, thin wind profile of the circumstellar medium, and so on. Depending on the models, the TeV emission of the early...
If dark matter is composed of axions, then axion stars form in the cores of dark matter halos. These stars are unstable above a critical mass, decaying to radio photons that heat the intergalactic medium, offering a new channel for axion indirect detection. Axion star decays lead to efficient reionization of the intergalactic medium during the dark ages. By comparing this non-standard...
Gamma-ray bursts (GRBs) are the most luminous explosions in the Universe. Thanks to the recent observations by ground-based gamma-ray telescopes, we now know that at least a class of GRBs are able to emit very-high-energy (VHE) gamma-ray emission. Starting from GRB 190114C detected by the MAGIC telescopes, in total there are five reports of VHE detection so far from MAGIC, H.E.S.S. and LHAASO....
In this paper, we present an analysis of the generalised Chaplygin gas (GCG) in the presence of bulk viscosity. Reconstruction techniques have been shown in the context of interacting scenarios and viscous cosmological settings using the Einstein and modified $f(T)$ gravity paradigm (where $T$ is the torsion scalar). Additionally considered are instances that are not viscous. Under different...
Dark matter energy injection in the early universe modifies both the ionization history and the temperature of the intergalactic medium. In this work, we improve the CMB bounds on sub-keV dark matter and extend previous bounds from Lyman-$\alpha$ observations to the same mass range, resulting in new and competitive constraints on axion-like particles (ALPs) decaying into two photons. The...
The search for multi-wavelength counterparts to fast radio bursts (FRBs) remains critical for understanding the underlying emission mechanisms of these interesting cosmological probes. The deepest limits come from telescopes with the fastest sampling rates in every band, meaning Imaging Atmospheric Cherenkov Telescopes (IACTs) are some of the most effective instruments to investigate these...
Elucidating the Majorana-Dirac nature of the neutrino remains a long-standing question, a discovery of which would provide unique and powerful insight into the building blocks of our Universe. The LEGEND (Large Enriched Germanium Experiment for Neutrinoless double beta Decay) experiment is designed to answer this very question. Using a large array of high-purity germanium (HPGe) detectors...
Palatini $F(R)$ gravity proved to be powerful tool in order to realize asymptotically flat inflaton potentials. Unfortunately it also inevitably implies higher-order inflaton kinetic terms in the Einstein frame that might jeopardize the evolution of the system out of the slow-roll regime. We prove that a $F(R-X)$ gravity, where $X$ is the inflaton kinetic term, solves the issue. Moreover, when...
The observation of coherent elastic neutrino nucleus scattering (CEvNS) has opened the window to many physics opportunities. In this talk I will discuss the implication of the observation of CEvNS by the COHERENT Collaboration using two different targets, CsI and argon, on new physics scenarios. These include, for instance, new light mediators and the possible production of a dark fermion.
Gamma-ray flares from Active Galactic Nuclei (AGN) show substantial variability on ultrafast timescales (i.e. shorter than the light crossing time of the AGN's supermassive black hole). I will show that ultrafast variability is a byproduct of the turbulent dissipation of the jet Poynting flux. Due to the intermittency of the turbulent cascade, the dissipation is concentrated in a set of...
SST-1M is a single-mirror Small Size Telescope prototype developed by a consortium of institutes from Poland, Switzerland and the Czech Republic. The design of the SST-1M follows the Davies-Cotton design, with a 9.42m$^2$ multi-segment mirror. With a wide field of view of 9 degrees, SST-1M is designed to detect gamma rays in the energy range between 1 and 300 TeV. The two SST-1Ms that have...
This talk will give an overview of the field of Dark
Matter Direct Detection, present recent highlights, and give a perspective
on the exciting prospects for the future.
The XENONnT experiment, located deep-underground in Laboratori Nazionali del Gran Sasso (Italy), is operating since 2020 with the aim of detecting dark matter direct interaction signals.
By exploiting a 5.9 t liquid Xenon target equipped with a Time Projection Chamber, as well as a combination of active veto systems and advanced purification techniques, the XENONnT experiment has reached an...
The LUX-ZEPLIN (LZ) experiment utilises a dual-phase xenon technology to search for dark matter in a wide range of WIMP masses. The setup includes xenon time projection chamber, xenon skin region and the outer detector made of Gd-loaded liquid scintillator. The detector is operating at the Sanford Underground Research Facility in Lead, South Dakota, USA. The detector has been calibrated with a...
The Recoil Directionality Experiment (ReD) aims at understanding if liquid Argon (LAr) experiments can determine the directionality of Dark Matter, as well as improving the measurement of very low energy nuclear recoils. For the latter, we study interactions of neutrons in our dual-phase LAr Time ProjectionChamber, in the 2 - 10 keV recoil energy region, determining its charge yield. This is a...
Light Dark Matter has recently gained a lot of attention. Generally, direct detection of sub-GeV Dark Matter is challenging since it induces low recoil energies. The problem is solved by considering light Dark Matter with considerable kinetic energies. In this talk, we point out that Primordial Black Hole evaporation is a source of boosted light dark Matter with energies of tens to hundreds of...
On Aug. 17, 2017, the merger of a binary neutron-star system observed through gravitational waves and multi-wavelength emissions, from gamma rays, X-rays, ultraviolet-optical-near-infrared, and radio, marked the history of multi-messenger astronomy, showing its enormous potential in probing the physics of the most energetic events in the Universe. Multi-messenger observations are a unique tool...
Gamma-ray bursts have been hypothesized as the sources of ultrahigh-energy cosmic rays. The direct evidence, however, is still missing. Recent detection of gamma-rays exceeding 10 TeV from the record-breaking “brightest of all time” or the B.O.A.T. burst GRB 221009A provides clues to whether UHECRs are accelerated and responsible for producing very high energy gamma rays. In this talk I will...
In October 2022, an extremly powerful and rare Gamma-Ray Burst, GRB 221009A, was observed by tens of space- and ground-based observatories, including both instruments onboard the Fermi Mission, the Large Area Telescope (LAT) and the Gamma-Ray Burst Monitor (GBM). The triggering pulse, detected by Fermi-GBM, was followed by a prompt phase lasting a few hundred seconds, and by an extended...
The production of the early emission of gamma‑ray bursts (GRBs) is still highly debated. We mostly rely on the wide field of view gamma‑ray instruments in the range of 10 keV-10 MeV. However, at higher energies (above 100 GeV), apparently, it is a critical job to catch it in flagrante. I will discuss the multi-messenger observational strategies to detect the early emission of short GRBs at...
Jetted AGNs, also called blazars when the jet is oriented toward the observer, are the brightest persistent γ-ray sources in the extragalactic sky.
The next generation Cherenkov Telescope Array Observatory (CTAO) will include telescopes with three different size to cover the full range of energy (from 20 GeV up to 300 TeV) in order to reach unpreceded capabilities in the observation of the...
The DarkSide-50 experiment uses a two-phase argon time projection chamber to directly search for dark matter interactions. The energy threshold of the detector can be lowered by including ionization-only events. While background rejection is lost, DarkSide-50's sensitivity is expanded to sub-GeV dark matter candidates. The DarkSide-50’s expanded search for several dark matter candidates with...
GW170817-GRB170817A provided the first direct evidence that at least a fraction of binary neutron star mergers (BNSs) are progenitors of short Gamma-Ray Bursts (sGRBs). More BNS signals are expected from the upcoming observation runs of the gravitational wave (GW) interferometers. In these systems, each messenger carries unique information about the astrophysical processes at the source. The...
Cosmic-ray (CR) antiparticles have the potential to reveal signatures of unexpected astrophysical processes and new physics. Recent CR detectors have provided accurate measurements of the positron flux, revealing the so-called positron excess at high energies. However, the uncertainties related to the modelling of the positron flux are still too high, significantly affecting our models of...
High-energy cosmic-ray electrons and positrons cool rapidly as they propagate through the Galaxy, due to synchrotron interactions with magnetic fields and inverse-Compton scattering interactions with photons of the interstellar radiation field. Typically, these energy losses have been modelled as a continuous process. However, inverse-Compton scattering is a stochastic process, characterised...
The next generation facility for gamma-ray ground-based observations is the Cherenkov Telescope Array (CTA) observatory, which encompasses three distinct sizes of imaging atmospheric Cherenkov telescopes (IACTs). Among these, the Large-Sized Telescopes (LSTs) of CTA, featuring a mirror dish with a diameter of 23 meters, are engineered to detect the faint atmospheric showers from the lowest...
DEAP-3600 is a single phase direct dark matter detector located at SNOLAB in Ontario, Canada. 255 photomultiplier tubes surround a spherical acrylic vessel to detect scintillation light from ~3300 kg of liquid argon. DEAP-3600 was designed to search for spin independent weakly interacting massive particles (WIMPs) and holds the leading WIMP exclusion using liquid argon.
Identifying...
Multimessenger astronomy is a new way of exploring the Universe by combining data from different cosmic messengers such as gravitational waves and electromagnetic radiation. One of the best astrophysical targets for performing multimessenger analysis is Binary Neutron Star (BNS) coalescences, which produce both gravitational waves and detectable multiwavelength electromagnetic emissions. The...
Supernova remnants shocks are considered the best sites for the production of Galactic cosmic rays. The interactions of cosmic rays produced at supernova shocks with photon fields and the interstellar medium generate a multi-wavelength spectrum from radio to gamma rays. In particular, TeV gamma-ray emission may originate from both hadronic and leptonic interactions. Recent results from kinetic...
The most recent catalog of extragalactic gamma-ray sources, based on data collected over a period of 10 years by the Fermi satellite, double its cataloge the number of blazars with respect to the previous catalog.
In this contribution, we study the updated blazar sequence built with this extended dataset and investigate the properties of the TeV-detected subsample of sources.
This study...
The COSINUS experiment (Cryogenic Observatory for SIgnatures seen in Next generation Underground Searches) is a low-threshold, cryogenic experiment being set up at Laboratori Nazionali Del Gran Sasso, Italy. It aims to provide a model independent cross-check of the DAMA/LIBRA findings of a potential dark matter-like modulation signal.
COSINUS utilizes a two-channel readout system based on...
The Pierre Auger Observatory, the largest ultra-high energy cosmic ray detector ever constructed, has an unprecedented sensitivity to neutral primaries above 10^17 eV.
After almost 20 years of data taking, stringent limits to the diffuse flux of photons and neutrinos have been derived, excluding many exotic models for the origin of UHE cosmic particles. Furthermore, targeted searches and...
The Spectral Energy Distribution (SED) of blazars consists of two components. The low-energy emission, extending from radio to X-rays, is interpreted as synchrotron radiation from accelerated electrons, while the high-energy radiation, which can reach TeV energies, is produced via inverse Compton scattering of the electrons by lower-frequency photons. The latter can come either from the...
The origin and acceleration mechanisms of Galactic cosmic rays (CRs) are still unknown. Gamma-ray observations have been crucial in identifying potential sites of CR acceleration. However, understanding these observations is challenging because both hadronic and leptonic processes can produce gamma rays, and different mechanisms may be responsible for accelerating various CR species. A...
The joint detection of a short GRB and gravitational waves had long been a goal by astronomers that was finally realized with GRB/GW 170817A. The GRB emission was much less luminous than expected though, with a peak luminosity more than two orders of magnitude lower than any other short GRB known. This implies that there is a population of low-luminosity short GRBs and greatly motivates more...
Observational studies have revealed correlations between the fluxes of X-rays and TeV gamma-rays in blazars, particularly in the context of the leptonic Synchrotron Self-Compton (SSC) model. The HBL blazar Mrk 421 exhibits a linear correlation between these two energy ranges, although it breaks down at the highest gamma-ray fluxes, suggesting the involvement of additional mechanisms like...
The central region of the Milky Way is a peculiar target even for observations at the highest energies in the gamma-ray regime. For that reason the Galactic Centre (GC) represents an ideal laboratory where studying physical processes and testing theories and models. A definitive and conclusive explanation of the measured flux at GeV and TeV bands is still unknown. Among the most plausible...
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/c2) and high mass (𝑀>100 𝐺𝑒𝑉/𝑐2) direct detection search for dark matter.
The next stage of the DarkSide program will be a new generation experiment involving a...
Core collapse supernovae are among the most energetic explosions in the modern Universe and one of the long-standing riddles of stellar astrophysics. The detection of a gravitational wave signal coming from a core collapse supernovae would be extremely interesting, due to the fact that it would give us the chance to probe the core dynamics of a dying massive star and, eventually, enlighten the...
Blazars are among the most intensively studied sources in high-energy astrophysics. Nevertheless, the exact acceleration processes of high-energy particles and emission mechanisms remain unclear. The recently launched IXPE satellite allows for the first time the measurement of polarisation in the X-ray band, hence opening a new window to the cosmos. The two TeV archetypical blazars Mrk421 and...
The SuperCDMS Collaboration is currently building a direct dark matter detection experiment at SNOLAB (Canada) consisting of an array of germanium and silicon crystals, with a total payload of 25 kg and 3.6 kg, respectively. Each crystal is instrumented to measure either a combination of phonon and ionization signals (iZIP detectors) or the phonon signal caused by charge carriers via the...
Cosmic rays (CRs) are trapped within the Milky Way and diffuse through the interstellar medium (ISM) for millions of years. This confinement and propagation process creates a pervasive ``sea'' of relativistic particles that interact with the diffuse gas, radiation, and magnetic fields in the ISM to produce secondary emissions over a broad energy range from all directions on the sky.
The...
Some of the most important open questions in particle physics are: What is dark matter? What is the origin of the domination of matter over antimatter in the Universe? How are neutrino masses generated? I will discuss how gravitational wave experiments can help us probe theories proposing solutions to the above puzzles. I will concentrate on a class of models in which baryon and lepton number...
Relativistic outflows or jets with more than 99% of the light speed emerge in pulsar wind nebulae, gamma-ray bursts, and active galactic nuclei. Such relativistic jets are thought to be launched through magnetic processes, which implies magnetically dominated outflows. However, a multi-wavelength spectrum suggests that jets must be kinetically dominated at the gamma-ray emission region. This...
The Telescope Array (TA) experiment is the largest observatory for ultra-high energy cosmic rays (UHECRs) in the northern hemisphere. The TA experiment, along with its low-energy extension (TALE), employs plastic scintillator detectors and fluorescence detectors to observe cosmic-ray-induced air showers ranging from 2 PeV and 100 EeV. In this presentation, we provide an overview of the current...
A range of haloscope searches are currently probing axions in the mass range ~2-40 μeV. However, simulations of the axion field in the early Universe are increasingly pointing towards heavier masses if we want the axion to comprise all of the Dark Matter in the Universe. I will briefly review these developments and then I will present The Canfranc Axion Detection Experiment (CADEx), a proposed...
I will show that a new gravitational wave signature is expected in extensions of the Standard Model with extra gauge symmetries broken at vastly different energy scales. The spectrum contains a characteristic double-peak structure consisting of a sharp peak from domain walls and a smooth bump from a first order phase transition in the early Universe. I will provide an example of such a model,...
M87 was discovered as a very-high-energy gamma-ray emitter (VHE, E > 100 GeV) with HEGRA in 2003, even before its high-energy gamma-ray emission (HE, E > 100 MeV) was detected. These observations established M87 as the first extragalactic source with a tilted jet detected up to the TeV energies. After the major VHE flares in 2005, 2008, and 2010, M87 has been mainly observed in a quiescent low...
The CYGNUS proto-collaboration aims to establish a Galactic Directional Recoil Observatory at the ton-scale that could test the DM hypothesis beyond the Neutrino Floor and measure the coherent and elastic scattering of neutrinos from the Sun and possibly Supernovae. A unique capability of CYGNUS will be the detailed measurement of topology and direction of low-energy nuclear and electron...
In this contribution, we present the energy spectrum using data acquired from the Pierre Auger Observatory. By integrating six distinct methodologies, we measured the spectrum from 6×10$^{15}$ eV up to beyond 10$^{20}$ eV. With an accumulated exposure of over 80,000 km$^2$ sr yr above the ankle region, it represents the most accurate spectrum estimation ever achieved within this energy range....
I will discuss new types of gravitational wave signatures which arise in extensions of the Standard Model with two U(1) gauge symmetries broken at high energy scales, focusing on the case when those symmetries are gauged baryon and lepton number. Such theories accommodate dark matter, leptogenesis, and the seesaw mechanism for neutrinos. The gravitational wave spectrum consists of...
The emission mechanisms and regions of multi-wavelength photons from radio galaxies are unknown. The emission from Magnetically Arrested Disks (MADs) with strong magnetic fields at the center of radio galaxies can explain the high-energy gamma-ray data, but the MAD model cannot explain the observational X-ray data. One possible scenario to explain radio to X-ray data is the emission from jets....
Understanding the gravitational wave signals from cosmological sources, such as first order phase transitions and cosmic strings, is currently a popular and active area of research. Such sources can also produce energetic particles, such as gamma rays, neutrinos, and dark matter, thereby producing distinct particle astrophysics signals. This talk will provide a broad discussion of the...
The origin of cosmic rays has been one of the motivating questions of the astrophysics field for over a century, an open and exciting topic since then. To help answer this question, the Pierre Auger Observatory investigates the anisotropies of the ultra-high-energy cosmic rays (UHECRs) — with energies above ${\sim}32$${\,}$PeV — at small, intermediate, and large angular scales. The Observatory...
The SABRE (Sodium iodide with Active Background REjection) experiment aims to detect an annual rate modulation from dark matter interactions in ultra-high purity NaI(Tl) crystals in order to provide a model independent test of the signal observed by DAMA/LIBRA. It is made up of two separate detectors; SABRE South located at the Stawell Underground Physics Laboratory (SUPL), in regional...
This talk presents a novel approach to dark matter direct detection using anomaly aware machine learning techniques in the DARWIN next-generation dark matter direct detection experiment. I will introduce a semi-unsupervised deep learning pipeline that falls under the umbrella of generalized Simulation Based Inference (SBI), an approach that allows one to effectively learn likelihoods straight...
The Pierre Auger Observatory is the largest facility for the study of ultra-high energy cosmic rays (UHECRs). After nearly 20 years of successful operation, the observatory has provided many new insights about the spectrum, anisotropies and composition of UHECRs. However, more precise measurements are needed to obtain a complete picture about the nature and origin of these particles, to...
NGC1068 is a Seyfert II starburst galaxy emitting in a very broad range of frequencies, from radio up until gamma-ray energies. Since the observed high-energy neutrinos and gamma-rays fluxes are different by at least 2 orders of magnitude, it becomes necessary to account for a multi-component model to describe the multimessenger emission by NGC1068. The neutrinos signal can be explained...
Recent associations of high-energy neutrinos with active galactic nuclei (AGN) have revived the interest in leptohadronic models of radiation from astrophysical sources. The rapid increase in multi-messenger observations requires fast numerical models that may be applied to large source samples. In this contribution, we introduce LeHaMoC, a newly developed code for solving (using an implicit...
We explore two generic hypotheses for tracing the sources of ultra-high energy cosmic rays (UHECRs) in the Universe: star formation rate density or stellar mass density. For each scenario, we infer a set of constraints for the emission mechanisms in the accelerators, for their energetics and for the abundances of elements at escape from their environments. From these constraints, we generate...
In this talk, I will explore the potential for uncovering new neutrino physics through the use of dark matter direct detection experiments and its complementarity with spallation source experiments. In particular, I will analyse the Sterile Baryonic Neutrino Model, an extension of the SM in which we add a sterile massive neutrino. I will show how the sterile neutrino can be generated through...
PKS 1510-089 is the only known flat spectrum radio quasar with persistent very-high-energy (E>100GeV) gamma-ray emission. It also showed varying and complex variability and correlation patterns, which were hard to explain within a single-zone emission model. Here, we present recent observations with H.E.S.S., Fermi, Swift, ATOM and SALT. These suggest that PKS 1510-089 used to have at least...
In 2013, the IceCube collaboration announced the detection of diffuse high-energy astrophysical neutrino flux. The origin of these particles is still unknown as there is still no identification of a source at the 5-sigma level. To answer this question, IceCube releases realtime alerts triggering follow-up observations in multiple wavelengths looking for electromagnetic counterparts to...
In this study, we systematically studied the X-ray to GeV gamma-ray spectra of 61 Fermi/LAT-detected radio galaxies. We found an anticorrelation between peak frequency and peak luminosity in the high-energy spectral component of radio galaxies, similar to blazars. With this sample, we also constructed a gamma-ray luminosity function (GLF) of gamma-ray-loud radio galaxies. We found it is a...
LHAASO-KM2A is composed of 5915 scintillation detectors and 1188 muon detectors. The muon detectors cover 4% of the total array area, with an inter-detector spacing of 30 meters. This report is based on the data samples recorded by LHAASO-KM2A from August 2021 to July 2022 with zenith angle $θ<40°$, which energy is estimated around $10^{14}-10^{16.7}$eV. The Monte Carlo samples are produced...
Dark matter particles with sub-GeV masses can be notoriously difficult to probe, because their typical momenta are insufficient to induce nuclear recoils above the thresholds of conventional direct detection experiments. In fact, it has repeatedly been claimed that even very strongly interacting dark matter could hide in this mass range, supposedly evading all observational bounds. In this...
Multimessenger observation of neutrino sources is a key for identifying the origin of astrophysical neutrinos, and it led to the identification of the blazar TXS 0506+056 as the first candidate in 2017. When the IceCube observatory detects likey astrophysical neutrino events, alerts are sent to the other telescopes to trigger follow up observations. A newly proposed algorithm is optimized to...
The evidence for the existence of non-baryonic dark matter is overwhelming, coming from many different scales. However, there are still no positive signals. Indeed, the upper limits from direct detection have improved by several orders of magnitude in the last decades. In this talk, we will discuss several novel directions in WIMP model-building. We will analyse different scenarios (complex...
The catalog of TeV-emitting sources (TeVCat) comprises six Fanaroff-Riley type I (FR I) radio galaxies. Unlike blazars, the jets of radio galaxies point away from the observer’s line of sight. Therefore, despite their small number, these sources, not entirely dominated by the jet component, offer a unique opportunity to investigate high-energy processes from a different perspective.
Among...
To detect the cosmic neutrino flux at the highest energies, Askaryan radio detectors are being deployed in the polar regions. These detectors use the radio detection technique to cover multi-gigaton detection volumes to probe neutrino interactions in the polar ice. Cosmic ray showers can serve as essential calibration sources for in-ice Askrayan radio detectors. However, if not well...
In addition to its implications for astrophysics, the hunt for neutrinos from Gamma-Ray Bursts (GRBs) could also be significant in quantum-gravity research, since they are excellent probes of the microscopic fabric of spacetime. Over the last few years one of the most studied candidate effects of quantum gravity has been in-vacuo dispersion, a phenomenon suggesting an energy-dependent speed...
FIMP dark matter is produced via the freeze-in mechanism that generally implies tiny couplings between the Dark Matter (DM) and the Standard Model particles, making DM direct detection hopeless. When the interaction is non-renormalizable the coupling is automatically suppressed by the scale of new physics and the production depends strongly on the reheating temperature. A natural candidate, in...
The PeV-EeV range of the cosmic ray energy spectrum is a complex region that probably harbours the transition from Galactic to extragalactic origins. It is unclear where this transition occurs and whether a secondary Galactic component is required to explain the observations. Measuring the mass composition of cosmic rays is essential to disentangle the fluxes and gain better understanding of...
Standard models of the large-scale interstellar emission officially adopted so far for studies of the Fermi-LAT data are very uncertain and show some discrepancies with respect to the data especially in the inner Galaxy where the degeneracy with the various components is large, underlining the necessity of more realistic models.
We focus here on the large-scale Inverse Compton (IC) component...
The challenges inherent to time-domain multi-messenger astronomy require strategic actions to perform suited, optimized follow-up observations efficiently. Poorly localized events require dedicated tiling and/or targeted follow-up campaigns so that the source location can be efficiently covered, increasing the chances to detect the multi-wavelength counterpart. We have developed the python...
The High Energy cosmic-Radiation Detection (HERD) facility is a calorimetric space-borne experiment for the direct detection of cosmic rays. It will be launched and installed onboard the China Space Station in 2027. The ambitious aim of HERD is the direct detection of cosmic rays in the "knee" region (~ 1 PeV), with a detector able to measure electrons, photons and nuclei with an excellent...
KM3NeT is a multi-site and multi-purpose neutrino telescope under construction in the depth of the Mediterranean Sea. It consists of two Cherenkov telescopes, ARCA (in Italy) and ORCA (in France), both of which are currently taking data with partial detector configurations. Among the primary scientific goals of KM3NeT is the observation of cosmic neutrinos and the identification of their...
Various short-baseline neutrino oscillation experiments have yielded unexpected results, which hint at the existence of light sterile neutrinos. IceCube has performed a unique search for sterile neutrinos by exploiting matter-enhanced resonant oscillations, which can be probed using atmospheric and astrophysical neutrinos in the TeV energy regime. The analysis uses the world’s largest sample...
The constituents of dark matter (DM) are still unknown, and the viable possibilities span a very large mass range. Specific scenarios for the origin of dark matter sharpen the focus on a narrower range of masses: the natural scenario where dark matter originates from thermal contact with familiar matter in the early Universe requires the DM mass to lie within about an MeV to 100 TeV....
CMS searches for dark matter including those with dark portal interactions are presented.
Various topologies and kinematic variables are explored. In this talk, we focus on the
recent results obtained using the full Run-II dataset collected at the LHC.
Many theories beyond the Standard Model (BSM) have been proposed to address several
of the Standard Model shortcomings, such as the origin of dark matter and neutrino
masses, the fine-tuning of the Higgs Boson mass, or the observed pattern of masses
and mixing angles in the quark and lepton sectors. Many of these BSM extensions
predict new particles or interactions directly accessible at...
The discovery of the Higgs boson with a mass of 125 GeV completed the particle
content predicted by the Standard Model (SM). Even though this model is well
established and consistent with many measurements, it is not capable to solely
explain some observations. Many extensions of the SM addressing such shortcomings
have additional (neutral or charged) Higgs bosons. In some models, the...
In this talk I will give a theorist point of view of the status of our quest for physics beyond the standard model of particle physics. One decade after the discovery of the Higgs boson many of the theoretical questions remain the same. I will review how our view of these questions
has been impacted by experimental data. I will give some examples of what I consider to be interesting ideas to...
The QCD axion -- which emerges as a solution to the strong CP problem -- would unavoidably contribute both the dark matter and dark radiation in the early and present Universe. The rich phenomenology brought in by the theory of the QCD axion depends on various components such as the axion energy scale, the details of the production mechanism, and the thermal history of the early Universe. We...
The indirect detection program looks for annihilation and decay products of dark matter from astrophysical sources. In its high-mass regime, it offers the only way to get ‘right here, right now’ constraints on many motivated scenarios. I will describe two possible stories for dark matter at or beyond the weak scale, and current & projected limits on them. The first is the case of vanilla...
An intriguing possibility is that multiple dark matter (DM) candidates can coexist and contribute significantly to its measured relic abundance. In R-parity conserving supersymmetric models, the MSSM and the next-to-MSSM extended with RH neutrino superfields, we study a two-component scenario with right-handed sneutrino NLSP and gravitino LSP as DM candidates. Interestingly, the right-handed...
The microphysics of Dark Matter (DM) remains an open question in high energy physics and cosmology. Given the diversity of particles in the Standard Model (SM), it is plausible that DM is also composed of more than one type of particle organized in a “dark sector”. In case of inelastic or pseudo-Dirac DM, the dark sector consists of two nearly mass-degenerate states. These can participate in...
Sterile neutrinos are a well-motivated and simple dark matter (DM) candidate. However, sterile neutrino DM produced through oscillations by the Dodelson-Widrow mechanism are in tension with current $X$-ray observations. To preserve the attractive features of this scenario, self-interactions among sterile neutrinos have been proposed as a minimal extension of the production mechanism. In this...
More than a decade ago, the Large Area Telescope aboard the Fermi Gamma-ray Space Telescope unveiled the existence of two gigantic gamma-ray lobes known as the Fermi Bubbles. While their origin is still unknown, various studies identified intricate structures within the bubbles. One prominent region, the cocoon, has recently been associated with gamma-ray emissions from the Sagittarius dwarf...
Despite the wealth of gravitational evidence, little is known about the nature of dark matter. Searches for dark matter with liquid xenon (LXe) Time Projection Chamber (TPC) experiments have focused on the traditional mass range of weakly interacting massive particle (WIMP) dark matter candidates from a few GeV/$c^2$ to hundreds of TeV/$c^2$. The lack of WIMP signal thus far motivates a...
HEX-P is a probe-class mission concept that will combine high spatial resolution X-ray imaging (<10 arcsec FWHM) and broad spectral coverage (0.1-150 keV) with an effective area far superior to current facilities (including XMM-Newton and NuSTAR) to enable revolutionary new insights into a variety of important astrophysical problems. HEX-P is ideally suited to address important problems in the...
We estimated the contribution from clusters of galaxies to the diffuse neutrino and $\gamma-$ray background. Due to their unique magnetic-field configuration, CRs with energy $\leq10^{17}$ eV can be confined within these structures over cosmological time scales, and generate secondary particles, including neutrinos and gamma-rays, through interactions with the background gas and photons. We...
TXS 0506+056, source of the extreme energy neutrino event, IceCube-170922A, has an interesting environment to study the lepto-hadronic emissions. The Fermi-LAT detector reported high energy (HE) γ-ray flare between 100 MeV and 100 GeV starting from 15 September 2017 from this source. Several follow-ups to trace the very high energy (VHE) gamma-ray counterparts around the IceCube-170922A...
We propose a new search strategy for higgsinos. Assuming associated production of higgsino-like pairs with a W or Z boson, we search in the missing energy plus hadronically-tagged vector boson channel. We place sensitivity limits for (HL-)LHC searches assuming (1–3.5 GeV) mass differences between the lightest neutral and charged states. We point out that using the $E_T^{\mathrm{miss}}$...
We are going to present the CYGNO/INITIUM project for the development of an high precision optical readout gaseous Time Projection Chamber (TPC) for directional Dark Matter search and solar neutrino spectroscopy, to be hosted at Laboratori Nazionali del Gran Sasso (LNGS). CYGNO peculiar features are the use of sCMOS cameras and PMTs coupled to GEMs amplification of an helium-fluorine based gas...
Recently IceCube observed TeV neutrino emission from the nearby Seyfert type-II Galaxy, NGC 1068, which suggests that AGN could potentially be one type of source of the diffuse high-energy astrophysical neutrino flux. Disk-corona models, which predict neutrino emission using the observed keV X-rays luminosity from the Seyfert galaxies, are employed to search for similar sources. In this...
Particle physics is at a crossroads: new physics is there, but we do not know where to search for it. Astrophysics and cosmology offer many opportunities to reduce the parameter space for new physics. In this talk, I will focus on a potential relic that could bring us invaluable information about processes in the early universe and, thus, about new physics. Strong hints from gamma-ray...
We investigate different classes of models, in which the dark matter candidate arises
as a hadronic state of dark constituent quarks, which are charged under both the new
confining dark gauge group and the standard model. Specifically, we focus on the case
of quarks in the fundamental representation of SU(N), which are heavier than the dark
QCD confinement scale. Recent literature has...
The presence of dark matter can explain several observations in the universe. However, its nature is still unknown. Therefore, the study of dark matter is a rapidly evolving field. New techniques and methods are being applied all the time. The measurement of the direction of WIMP-induced nuclear recoils is a challenging strategy to extend dark matter searches beyond the neutrino floor...
Recent observations have revealed that Tidal Disruption Events (TDEs), caused by the gravitational disruption of a massive star close to a supermassive black hole (SMBH), can produce intense flares of radiation with the duration of months to years. Notably, three TDE candidates (AT2019dsg, AT2019fdr, and AT2019aalc) are likely associated with IceCube astrophysical neutrinos. In this talk, I...
The observed dark matter relic abundance may be explained by different mechanisms,
such as thermal freeze-out/freeze-in, with one or more symmetric/asymmetric components.
In this work we investigate the role played by asymmetries in determining the
yield and nature of dark matter in non-minimal scenarios with more than one dark matter
particle. In particular, we show that the energy...
We employ a non-relativistic effective theory to model dark matter (DM) induced electron ejections from graphene and carbon nanotubes (CNTs), materials currently in the R&D phase for direct detection experiments. The material properties of graphene are modelled using Density Functional Theory, and we obtain observable ejection rates for arbitrary forms of scalar and spin-1/2 DM. We show how...
A robust spectrum of gamma-ray emissions from solar disk reaches up to 200 GeV with no cutoff has been reported with Fermi-LAT. Recent results from HAWC also extended the energy up to 1 TeV. Many startling mysteries and open questions have shown up along with the unknown mechanism to understand its spectrum, time variability, and morphology. Any significant observation signals or a strong...
Recent radio observations of tidal disruption events (TDEs) show that some TDEs exhibit late time emission, which may be due to delayed jet launch from the central engine. The multi-messenger observations of several TDEs (AT2019dsg, AT2019fdr, and AT2019aalc) by IceCube and optical telescopes also provide evidence for the possibility of late time engine activity. In this work, we address this...
To date, the majority of experimental dark matter searches have been focused on the on the Weakly Interacting Massive Particle (WIMP) in the 100-1000 GeV/c^2 mass range, which would be a natural extension to the Standard Model. However, there are well-motivated theoretical models which postulate that the properties and interactions of dark matter in the early universe generated the abundance...
Despite its very close proximity to Earth, there are still many unsolved puzzles about the Sun. One such example of significant recent interest relates to the gamma-ray emission (in the GeV-TeV range) from the solar disk. A major contribution to the solar emission in this energy range is believed to be caused by the interaction of galactic cosmic rays (GCRs) with the solar atmosphere: the...
Since their discovery, cosmic rays (CRs) remain among the most mysterious phenomena of modern Physics. The dominant sources, as well as the exact acceleration mechanisms, remain unknown. The CRs up to the ``knee’’ have traditionally been considered to originate entirely in the shock waves of supernova remnants (SNRs), however, due to the lack of a “smoking-gun” TeV counterpart in many cases,...
The NA62 experiment at CERN took data in 2016–2018 with the main goal of measuring the $K^+ \rightarrow \pi^+ \nu \bar\nu$ decay. The NA62 dataset is also exploited to search for light feebly interacting particles produced in kaon decays. Searches for $K^+\rightarrow e^+ N$, $K^+ \rightarrow \mu^+ N$ and $K^+ \rightarrow \mu^+ \nu X$ decays, where N and X are massive invisible particles, are...
The well-studied graviton-to-photon conversion process provides an intriguing method to observe early universe gravitational wave sources. However, these effects are suppressed when considering magnetic fields present in the early universe, due to the presence of the Standard Model plasma. In contrast, a dark magnetic field would induce a graviton-to-dark photon conversion process, but not be...
Minerals are solid state nuclear track detectors - nuclear recoils in a mineral leave latent damage to the crystal structure. Depending on the mineral and its temperature, the damage features are retained in the material from minutes to timescales much larger than the age of the Solar System. The damage features from the fission fragments left by spontaneous fission of heavy unstable isotopes...
The Sun emits gamma rays ranging from several hundred MeV to 1 TeV through hadronic cosmic ray interactions with the solar atmosphere. A critical factor influencing this phenomenon is the reflection of cosmic rays by solar magnetic fields in the photosphere and the upper convection zone. In this talk, I will present a simplified solar magnetic flux tube structure that combines network elements...
SND@LHC is a compact experiment proposed to exploit the high flux of energetic neutrinos of all flavours from the LHC in a hitherto unexplored pseudo-rapidity region of 7.2 < 𝜂 < 8.4, complementary to all the other experiments at the LHC. The experiment is located 480 m downstream of IP1 in the unused TI18 tunnel. The detector is composed of a hybrid system based on an 830 kg target mass of...
As the WIMP draws under increasing tension thanks to the ever increasing sensitivity of direct detection experiments, the majority of dark matter parameter space outside of the weak scale remains unexplored. Molecular and nano-scale systems are particularly well-suited to look for sub-GeV DM since their eV-scale electronic transitions may be excited through light dark matter interactions....
In this contribution, we present the latest updates introduced to agnpy - an open-source python package for modeling broadband spectra of blazars.
Among the significant updates, we discuss the implementation of hadronic radiative processes. The agnpy software now implements proton synchrotron radiation and we are working also to implement the photohadronic process. Additionally, we...
Gamma-ray bursts (GRBs) have late-time emission components lasting 100-1000 seconds, such as extended emission of short GRBs and X-ray flares of long GRBs. These components could be explained by the internal dissipation of the jets produced by prolonged central engine activity, and could be influenced by the materials around the jet. The prompt jet interacts with the progenitor star or the...
We will given an overview of recent developments in numerical modelling of cosmic-ray transport and ensuing gamma-ray emission within our Galaxy using the Picard code. Picard is a cosmic-ray propagation code allowing for efficient solution of spatially three-dimensional models. We will discuss challenges at arriving at the necessary three-dimensional models of our Galaxy that determine the...
Over the past decade, the IceCube detector has gone from the discovery of an astrophysical neutrino flux at earth to the identification of two neutrino sources, TXS 0506+056 and NGC 1068. However, efforts continue within IceCube to pull more astrophysical neutrino events out of the data. Here, we present the results from a new IceCube event sample which selects for starting track events...
Searches in CMS for dark matter in final states with invisible particles recoiling against
visible states are presented. Various topologies and kinematic variables are explored,
including jet substructure as a means of tagging heavy bosons. In this talk, we focus on
the recent results obtained using the full Run-II dataset...
The Galactic Center Gamma-Ray Excess has a spectrum, angular distribution, and overall intensity that agree remarkably well with that expected from annihilating dark matter particles in the form of a ~50 GeV thermal relic. Previous claims that these photons are clustered on small angular scales or trace the distribution of known stellar populations once appeared to favor interpretations in...
IceCube, a cubic-kilometer Cherenkov Neutrino detector located at the South Pole has been able to put constraints on the diffuse astrophysical neutrino flavour ratio measured on Earth by establishing the existence of the astrophysical tau neutrino component of the neutrino flux. This measurement was made using the High Energy Starting Event (HESE) sample collected for over 7.5 years containing...
About one third of the Fermi-LAT sources have no high probability associations. Some of the sources may have no observable counterparts at other frequencies, such as pulsars with misaligned radio jets. For these sources probabilistic classification, e.g., with machine learning (ML), may be the only possibility to understand their nature. One of the main problems in using ML for classification...
The nature of the GeV gamma-ray Galactic center excess (GCE) in the data of Fermi-Large Area Telescope (LAT) is still to be unveiled. While the GCE photon flux is peaked at about few GeV, a high energy tail extending up to tens of GeV has been reported by various studies. If confirmed, such high-energy photons are naturally explained by the inverse Compton emission of electrons and positrons...
The presence of a non-baryonic Dark Matter (DM) component in the Universe is
inferred from the observation of its gravitational interaction. If Dark Matter
interacts weakly with the Standard Model (SM) it could be produced at the LHC. The
ATLAS Collaboration has developed a broad search program for DM candidates in final
states with large missing transverse momentum produced in association...
The nature of Dark Matter is one of the important unresolved questions in fundamental physics. It is assumed in many Beyond Standard Model theories that dark matter candidates can have weak coupling to Standard Model (SM) particles. In heavy cosmological objects, like galaxies, the Sun, or the Earth, dark matter can be gravitationally accumulated to a high abundance such that it can decay or...
Starting track events in the IceCube Neutrino Observatory, a gigaton ice-Cherenkov detector at the South Pole, arise from muon neutrino and antineutrino charged-current interactions in the detector. By reconstructing the energies of the hadronic shower and secondary muon separately, one can obtain the inelasticity of the event. This observable enables various measurements, including the ratio...
The IceCube Neutrino Observatory is situated at the geographic South Pole. IceCube is composed of two detectors. One is an in-ice optical array that is sensitive to high-energy muons from air showers as well as particle cascades that are induced by high-energy neutrino interactions in the ice. The other detector, called IceTop, is an array of ice-cherenkov tanks on the surface above the in-ice...
Collider searches for dark matter (DM) so far have mostly focussed on scenarios
where DM particles are produced in association with heavy standard model (SM)
particles or jets. However, no deviations from SM predictions have been observed.
Several recent phenomenology papers have proposed models that explore the
possibility of accessing the strongly coupled dark sector, giving rise to...
Some candidates for the theory of quantum gravity allow for Lorentz invariance violation (LIV). If Lorentz's invariance is violated, it may cause an observable effect on the very high energy (VHE, E > 100 GeV) light curves and spectra of cosmic sources emitting gamma-ray photons. One of the possible consequences of the LIV is in-vacuo dispersion which implies that the photon group velocity is...
The IceCube collaboration has recently found evidence for connecting the blazar TXS 0506+056 to high-energy neutrino events. Observations of spatial correlations between neutrino hotspots and locations of blazars have also hinted at a blazar-neutrino connection (Buson et al. 2022, 2023). Several other studies have independently investigated the hypothesis of blazars as neutrino emitters with...
We started a new air shower observation experiment, ALPACA, to observe cosmic gamma rays and cosmic rays of several TeV or more from the southern sky of the galaxy.
The ALPACA’s location is at an altitude of 4,740 m on the hillside in Chacaltaya, Bolivia,
The ALPACA consists of a ground-based air shower detector array of 401 scintillation detectors and a large-area water Cherenkov-type...
Historically, dark matter searches have primarily focused on hunting for effects from two-to-two scattering. However, given that the visible universe is primarily composed of plasmas governed by collective effects, there is great potential to explore similar effects in the dark sector. Recent semi-analytic work has shown that new areas of parameter space for dark U(1) and millicharged models...
The Micromegas detectors are part of the New Small Wheel (NSW) system of the ATLAS experiment, the largest upgrade project of Phase-1. Together with sTGC detectors they provide trigger and tracking capability in the innermost station of the end-cap part of the Muon spectrometer.
The Micromegas detector of ATLAS cover an active area of about 1280 m^2, has 1024 HV channels and 2.1 M readout...
AGN are powerful sources that are believed to be capable of accelerating particles to high energies. In environments with gas or photon targets, cosmic-ray interactions transpire leading to the production of pionic gamma rays and neutrinos. Since the AGN environment is rich in gas, dust and photons, they are promising candidate sources of high-energy astrophysical neutrinos. While the...
The Southern Wide-field Gamma-ray Observatory (SWGO), currently in the R&D phase, is the project to design and build the first wide-field ground-based observatory in the Southern hemisphere, for the detection of gamma-rays from a few hundred GeV to a few PeV. The extensive air shower array, planned for deployment at an altitude greater than 4400 m a.s.l., will be primarily based on water...
Milli-charged particles (MCP) can be produced through the decay of plasmon in stellar interiors and escape stars without interactions. This extra cooling could alter the brightness of low mass stars at the tip of the red giant branch (RGB). While the current stellar cooling bounds were obtained by estimating the total expected heat loss given the current stellar properties, we improve the...
The IceCube Neutrino Observatory measures astrophysical and atmospheric neutrinos from the entire sky. The detector array measures Cherenkov light emitted when neutrinos interact in the ice and produce charged leptons. The presence of astrophysical neutrinos has been established by the High Energy Starting Events (HESE) selection. HESE measures these astrophysical neutrinos at energies above...
The Galactic Explorer with a Coded Aperture Mask Compton Telescope (GECCO) is a novel concept for a next-generation telescope covering the MeV band. We will present the potential and importance of this approach that bridges the observational gap between the keV and GeV energy range. With the unprecedented angular resolution of the coded-mask telescope combined with the sensitive Compton...
Instantons can give rise to decay of particles otherwise forbidden. Using data collected at the Pierre Auger Observatory, we present a search for signatures of such instanton-induced decay processes that could be at work for super-heavy particles produced sufficiently during the post-inflationary epoch to match the relic abundance of dark matter inferred today. The non-observation of these...
Galaxy Clusters are considered to be efficient containers of cosmic rays (CRs). In their formation history, CRs are accelerated by active galactic nuclei, and cosmological shocks and turbulence, and they are accumulated in the intra-cluster space. The magnetic field and cosmic ray electrons in massive clusters have been proved with the observations diffuse radio emission. However, the content...
The Compton Spectrometer and Imager (COSI) is a Small Explorer satellite mission selected by NASA and scheduled to launch in 2027. COSI employs a novel Compton telescope consisting of a compact array of cross-strip germanium detectors. Owing to its wide field-of-view and excellent energy resolution, COSI will achieve an unprecedented sensitivity in the MeV range, especially for gamma-ray...
Earth neutrino tomography is a realistic possibility with current and future neutrino detectors, complementary to geophysics methods. The two main approaches are based on either partial absorption of the neutrino flux as it propagates through the Earth (at energies about a few TeV) or on coherent Earth matter effects affecting the neutrino oscillations pattern (at energies below a few tens of...
The Large-Sized Telescope (LST-1) is the first 23-m-diameter prototype telescope for the Cherenkov Telescope Array Observatory (CTAO) and it is able to perform high-sensitivity observations in the energy band from 20 GeV to 20 TeV. The telescope is in its commissioning phase and is performing regular observations on a wide range of astrophysical sources in order to verify its scientific...
The CALorimetric Electron Telescope (CALET) is a Japan-led experiment installed on the International Space Station (ISS) in collaboration with Italy and the United States. It was developed with the purpose to carry out precision measurements of high energy cosmic-rays (CR), to investigate their origin, the mechanisms of acceleration and galactic propagation, and the presence of possible nearby...
The kilometer-square array (KM2A) of the Large High Altitude Air Shower Observatory (LHAASO, located at 4410 m above sea level with an atmospheric depth of 600 ) can simultaneously measure air shower sizes of both electromagnetic particles and muon contents with high precision for cosmic rays with energies in the knee region. The energy is reconstructed by combining parameters of muons and...
Pulsars and their associated pulsar wind nebulae are known to be efficient particle accelerators and antimatter factories in our Galaxy; the Crab nebula is the only leptonic accelerator firmly identified to date.
Observations at high and very high energies have shown in recent years that pulsar wind nebulae efficiently inject particles into the ambient medium, especially in their evolved...
Supernova remnants (SNRs) and pulsar wind nebulae (PWNe) are key classes of Galactic particle accelerators and are generally thought to be responsible for providing the bulk of cosmic rays in the Galaxy up to the knee. VERITAS observations of SNRs and PWNe in the very high energy (VHE; E > 100 GeV) range provide critical information to help us understand the nature of these accelerators,...
The Milky Way is the most prominent feature of the sky in all wavelengths of light. At the highest energies, the gamma-ray emission can tell us the story of cosmic rays in the Galaxy, but does not give us the possibility to distinguish between leptonic or hadronic emissions. This multi-wavelength scenario can be complemented by the observation of neutrinos; indeed, neutrinos can only come from...
Being for centuries a magnificent and enigmatic environment in the low energy regime, the Milky Way became, during the last decades, the prominent astrophysical lab to understand the high-energy diffuse emission produced by charged particles propagation and interactions with the interstellar medium. A Galactic cosmic-ray transport model featuring non-homogeneous transport has been developed...
