The Lunar Gravitational-Wave Antenna (LGWA) is a proposed detector which aims at revealing gravitational waves using the Moon as a detector and an array of seismic sensors as Moon-read-out. The concept is the same as that used for the gravitational waves bar detectors, which represent the first human attempt of measuring gravitational waves. With LGWA we will be sensitive in the deci-Hz...
Over the last six years, the LIGO and Virgo interferometers detected an increasing number of gravitational wave events. At the end of the third observing run, the wealth of GW candidates, most of which consist in the merger of binary black holes (BBHs), makes it possible to try to disentangle the formation channels of BBHs, thanks to their peculiar imprints.
In particular, the dynamical...
The detection of gravitational waves in 2015, thanks to the LIGO and Virgo interferometers, opened a new window on our Universe, and the era of Multimessenger GW–EM Astrophysics has started with the observation of GW170817–GRB170817A. The discoveries during the first three observing runs already had an extraordinary impact on both astrophysics, cosmology, and fundamental physics.
The GW...
As gravitational wave observatories discover more standard sirens, we
recognize that they can be an incisive probe of dark energy and gravity
in multimessenger combination with cosmic growth of structure.
Gravitational wave distance deviations from general relativity can be
related to growth deviations in many classes of gravity, providing deep
insight into cosmic physics. I also...
Gravitationally lensed multi-messenger transients are promising probes for constraining cosmological parameters including the Hubble constant. We focus on developing a deep learning technique to estimate lensing time delays from various multiply imaged unresolved transients. We train convolutional neural networks and apply them to simulated supernovae lightcurves to determine whether there...
Spinning neutron stars are sources of long-duration continuous waves that may be detected by interferometric detectors.
We focus on long-duration (transient) signals of unknown duration and start time.
We present a new method to identify them.
To investigate the Euclid Near Infrared Spectrometer and Photometer (NISP) capabilities, Spectral Energy Distribution (SED) models of galaxies located at 0.3 ≤z ≤2.5 have been constructed, simulated using the TIPS simulator of the NISP red grism, and analyzed focusing on emission lines measurements.
These simulations will enable evaluating the spectroscopic survey performances of the Euclid...
Understanding the accelerated expansion of the Universe is one of the challenges of modern cosmology. The various existing cosmological models that can explain the accelerated expansion differ in small variations in experimental observations. Detecting such variations requires a precise astronomical survey capable of covering most of the sky. For this purpose, the Euclid space mission was...
Euclid experiment will allow us to derive constraints on cosmological parameters and model selection through cross-correlation measurements between Cosmic Microwave Background (CMB) and Large Scale Structure (LSS). In this work we focalize on the detection of the late Integrated Sachs-Wolfe effect in order to constraint the density parameter for the dark energy $\Omega_{DE}$, the equation of...
Upcoming galaxy surveys will measure millions of spectroscopic galaxy positions over large sky areas and large redshift ranges, allowing to map in detail significant contiguous fractions of the observable Universe. High spatial resolution together with large volume allow to study cosmic voids in detail, making them a new effective probe for cosmology. In this talk, I focus on void abundance...
The GW170817 event provided the first observation of gravitational waves from a neutron star merger with associated transient counterparts across the entire electromagnetic spectrum. This discovery demonstrated the long-hypothesized association between short gamma-ray bursts and neutron star mergers. More joint detections are needed to explore the relation between the parameters inferred from...
In the last years, with the advent of multi-messenger astrophysics, the characterisation of binary systems of neutron stars has become central in various fields such as gravitational waves, gramma-ray bursts (GRBs), and the chemical evolution of galaxies. In this work, we explore possible observational proxies that can be used to infer some characteristics of the delay time distribution (DTD)...
The sensitivity of gravitational wave detectors is ultimately limited by
the quantum noise, which arises from the quantum nature of light and it is driven by vacuum fluctuations of the optical field entering from the dark port of the interferometer.
Quantum noise has two complementary features: the shot noise, which depends on phase fluctuations of the optical field disturbing the detector...
JUNO will be the largest ever built liquid scintillator detector for neutrino physics. It will be sensitive to various astrophysical neutrino sources, including solar neutrinos, the diffuse supernova neutrino background, pre-supernova neutrinos and the all-flavor neutrino flux from a Galactic core-collapse supernova (CCSN) with high statistics. For the purpose of maximizing the physics reach...
We develop a set of machine-learning based cosmological emulators, to obtain fast model predictions for the C(ℓ) angular power spectrum coefficients characterising tomographic observations of galaxy clustering and weak gravitational lensing from multi-band photometric surveys (and their cross-correlation). A set of neural networks are trained to map cosmological parameters into the...
S. Kovács$^1$, G. G. Kiss$^2$, Y. Saito$^3$, A. Vitéz-Sveiczer$^{1,2}$, A. Tarifeno-Saldivia$^4$, on behalf of the BRIKEN collaboration
$^1$ University of Debrecen, H-4032 Debrecen, Egyetem tér 1, Hungary
$^2$ Institute for Nuclear Research (ATOMKI), H-4026 Debrecen, Bem tér 18/c, Hungary
$^3$ TRIUMF, 4004 Wesbrook Mall, Vancouver, British Columbia V6T 2A3, Canada
$^4$ Universitat...
Matter expelled from binary neutron star (BNS) and black hole-neutron star (BHNS) mergers is one confirmed site capable of harboring r-process nucleosynthesis in the universe, due to its extreme conditions and abundance of neutrons. The freshly produced nuclei are unstable and undergo nuclear decay, releasing an amount of energy sufficient to power a thermal transient known as kilonova (KN). A...
The electromagnetic radiation that followed the neutron star merger event GW170817 revealed that gamma-ray burst afterglows from jets misaligned with our line of sight exhibit a light curve with slowly rising flux. The slope of the rising light curve depends sensitively on the angle of the observer with respect to the jet axis, which is likely to be perpendicular to the merger plane of the...
AGN jets are the most powerful persistent emitters in the Universe, but the mechanisms through which they dissipate part of their energy flux and convey it to relativistic particles are still elusive. Despite advances on the numerical and theoretical side, the identification of the processes at work is made difficult by the huge range of spatial and temporal scales involved and by the strong...
Pulsars are rotating neutron stars emitting a beam of radio light from their magnetic axis. As the pulsar signal passes through the interstellar medium (ISM), it gets smeared due to the variation of the group velocity of the radiation with wavelength caused by the electrons in the line of sight. This smearing can be due to dispersion by the integrated column density of electrons or multipath...
Joint observations of gravitational-wave (GW) event to compact binary objects mergers, and of their electromagnetic counterpart, known as kilonova (KN) lead to a new avenue in the multi-messenger astronomy era to constrain the astrophysical origin of the r-process elements and the equation of state of dense nuclear matter [1]. Coalescence of double neutron star releases n-rich ejecta which...
Highly differentially rotatig neutron stars can be produced in core-collapse supernova explosions. These objects may be significantly more massive than rigidly rotating neutron staers. Even for a modest degree of differential rotation we find equilibrium solutions with masses up to 4 times larger then the TOV limit. While the rotation profile evolves into uniform rotation on secular...
Gravitational waves provide us with an extraordinary tool to study the matter of neutron stars. In particular, the postmerger signal will reveal a lot of information about matter at such high densities. Although current detectors are mainly sensitive to the signal emitted by binary neutron stars during the inspiral and merger phase, the detectors’ improvements planned for the next observing...
Cosmological observations represent a powerful probe to test the presence of new light species beyond the Standard Model (SM) of particle physics. In this talk I will focus on thermal axion-like particles (which I will simply refer to as axions), that can arise from various extensions of the SM and include, as a special case, the QCD axion. Thermal axions can be produced in the early Universe...
We present an analytical modelling of the cross-correlation between the total (linear and nonlinear) ISW/Rees- Sciama effect and the galaxy distribution, in the presence of massive neutrinos. The modelling has been compared against sky-maps of CMB and galaxies extracted from the “Dark Energy and Massive Neutrino Universe” (DEMNUni) N-body simulations. We found a significant difference, in the...
The cosmological principle that the universe is homogeneous and isotropic at large scales is a fundamental assumption of modern cosmology. Recent observations of the galaxy redshift survey provide relevant data to confront the cosmic homogeneity with observation. Several previous studies claim that the homogeneity scale is reached at a radius around 70 Mpc/h. Here we present a homogeneity test...
The Laser Interferometer Space Antenna, LISA, is the ESA "L3" large mission, destined to be an orbiting observatory for gravitational waves in the 0.1 mHz to 1 Hz band. This will open a scientifically rich and deep window for astronomy, cosmology, and fundamental physics in a gravitational wave band that can only be reached from space. We present here the observatory science potential --...
The observation of the GW170817 event has shown how multimessenger astronomy is a powerful tool to investigate the most energetic phenomena in the Universe. Simulations are an important tool to study multimessenger emission and understand the constraints that can be put using joined electromagnetic and gravitational-wave observations. For that purpose, we developed the Gravitational Wave Sky...
The study of the X-ray sky, in particular transient sources, is an important part of the multimessenger astrophysics concurrent to Gravitational Waves and Neutrino Observations. It helps to understand different phenomena, e.g. the central engine and jet physics in compact binary mergers, the equation of state of neutron stars, cosmic accelerators, and the origin of Cosmic Rays (CRs), the...
Planned and proposed future gravitational wave detectors will observe huge numbers of binary mergers. It is timely to explore cosmological tests that can be performed with this forthcoming plethora of data, in combination with present and future galaxy surveys. We forecast a combined standard siren + weak lensing analysis, where perturbations in the propagation of gravitational waves by...
Gamma-ray astronomy studies the most extreme and violent phenomena in the Universe. Thanks to the continuous improvement in experimental techniques in the last decades a growing number of sources have been detected at very high energy showing a large variety of different types of emitters proving that particle acceleration and transport is occurring in different astrophysical conditions and...
In the new scientific era of multi-messenger astronomy, ultra-high-energy cosmic rays offer a very rare opportunity to investigate the nature of astro- physical sources and particle interactions at energies far from current particle accelerators capabilities. With almost 20 years of operation, the Pierre Auger Observatory is the world’s largest cosmic ray detector providing a unique data set...
The connection between ultra-high energy cosmic rays, photons, neutrinos and gravitational waves, in particular after the successful detection of gravitational waves, is nowadays widely investigated. Since all these signals may originate from the same sources, a multi-messenger approach, combining data from different experiments is undoubtedly the most appropriate technique for a better...
Active Galactic Nuclei are the most powerful persistent sources in the Universe. Among them, blazars, AGN whose jet is pointed towards the Earth, present the most energetic emission. Lately a specific kind of blazar drew the attention of the gamma ray astronomy community: the extreme TeV blazars. These sources exhibit a peak of radiation at TeV energies and a hard intrinsic spectrum at sub-TeV...
The Cryogenic Underground Observatory for Rare Events (CUORE) is the first bolometric 0νββ experiment to reach the one-tonne mass scale. The detector, located underground at the Laboratori Nazionali del Gran Sasso in Italy, consists of 988 TeO2 crystals arranged in a compact cylindrical structure of 19 towers, operating at a base temperature of about 10 mK. After beginning its first physics...
Gamma-Ray Bursts constitute one of the most fascinating and relevant
phenomena in modern science, with strong implications for several fields of astrophysics, cosmology and fundamental physics.
In this review, I will focus on the perspective key-role of GRBs for
cosmology and multi-messenger astrophysics. Indeed, the huge luminosity, the redshift distribution extending at least up to z~10...
The Planck collaboration has produced precise observations of the polarized synchrotron emission in the microwave band.
This emission is sensitive to the presence of a possible signal from Dark Matter annihilation or decay.
We use, for the first time, synchrotron polarization to constrain the DM annihilation cross section by comparing theoretical predictions with the latest polarization maps...
The detection of the gravitational event GW170817 is a turning point in nuclear astrophysics. Its observation triggered the investigation of the bright optical transient AT2017gfo using a broad number of diagnostic tools, opening the era of multimessenger astronomy. In particular, the follow-up of the lightcurve evolution made it possible to pinpoint the contribution from freshly synthesized...
Type Ia supernovae (SNe Ia) play a number of key roles in astrophysics. These include contributing substantially to cosmic nucleosynthesis, injecting kinetic energy in galaxy evolution and acting as cosmological distance indicators. Thanks to modern transient surveys it has become clear that type Ia supernovae are a diverse population with many different explosion scenarios proposed to explain...
Gamma-ray bursts are highly energetic cosmological objects that provide us with different paths towards a better understanding of fundamental physics and the evolution of the universe. The most recent, promising and innovative path developed, consists in estimating the Hubble cosmological constant from gravitational wave events for which the distance can be estimated through electromagnetic...
A cosmological-model independent reconstruction of the expansion history of the Universe can help to shed light on the dark sector and the current cosmological tensions. I will discuss past, present, and future efforts to constrain the Hubble parameter $H(z)$ using two optimal astrophysical probes: cosmic chronometers and gravitational waves. Massive and passive galaxies can be used as...
