A. V. Penacchioni
A5001442371- Gamma-ray bursts and supernovae
- Astrophysics and Cosmic Phenomena
- Astrophysical Phenomena and Observations
- Pulsars and Gravitational Waves Research
- Dark Matter and Cosmic Phenomena
- Astro and Planetary Science
- Astronomy and Astrophysical Research
- Neutrino Physics Research
- Particle Detector Development and Performance
- Astronomical Observations and Instrumentation
- Geophysics and Gravity Measurements
- Cosmology and Gravitation Theories
- Particle physics theoretical and experimental studies
- Radio Astronomy Observations and Technology
- High-pressure geophysics and materials
- Atmospheric Ozone and Climate
- Galaxies: Formation, Evolution, Phenomena
- Integrated Circuits and Semiconductor Failure Analysis
- Quantum, superfluid, helium dynamics
- Space Science and Extraterrestrial Life
- CCD and CMOS Imaging Sensors
- Laser-Plasma Interactions and Diagnostics
- SAS software applications and methods
- Advancements in Semiconductor Devices and Circuit Design
- Atomic and Subatomic Physics Research
Universidad Nacional de La Plata
2020-2025
Instituto de Física La Plata
2019-2025
Consejo Nacional de Investigaciones Científicas y Técnicas
2019-2025
University of Siena
2016-2019
International Center for Relativistic Astrophysics
2013-2018
Agenzia Spaziale Italiana
2016-2018
Waseda University
2018
Sapienza University of Rome
2011-2018
University of Pisa
2018
National Institute for Space Research
2014-2017
In this paper, we present the analysis and results of a direct measurement cosmic-ray proton spectrum with CALET instrument onboard International Space Station, including detailed assessment systematic uncertainties. The observation period used in is from October 13, 2015 to August 31, 2018 (1054 days). We have achieved very wide energy range necessary carry out measurements 50 GeV 10 TeV covering, for first time space, single whole interval previously investigated most cases separate...
First results of a cosmic-ray electron and positron spectrum from 10 GeV to 3 TeV is presented based upon observations with the CALET instrument on International Space Station starting in October, 2015. Nearly half million events are included analysis. an all-calorimetric total vertical thickness 30 ${X}_{0}$ fine imaging capability designed achieve large proton rejection excellent energy resolution well into region. The observed over can be fit single power law spectral index...
In August 2015, the CALorimetric Electron Telescope (CALET), designed for long exposure observations of high energy cosmic rays, docked with International Space Station (ISS) and shortly thereafter began tocollect data. CALET will measure ray electron spectrum over range 1 GeV to 20 TeV a very resolution 2% above 100 GeV, based on dedicated instrument incorporating an exceptionally thick 30 radiation-length calorimeter both total absorption imaging (TASC IMC) units. Each TASC readout channel...
Blazars research is one of the hot topics contemporary extra-galactic astrophysics. That because these sources are most abundant type gamma-ray and suspected to play a central role in multi-messenger We have used swift_xrtproc, tool carry out an accurate spectral photometric analysis Swift-XRT data all blazars observed by Swift at least 50 times between December 2004 end 2020. present database X-ray spectra, best-fit parameter values, count-rates flux estimations several energy bands over...
The joint X and gamma-ray observations of GRB 090618 by a large number satellites offer an unprecedented possibility testing crucial aspects theoretical models. In particular, it allows us to test (a) the formation optically thick e+e- baryon plasma self-accelerating Lorentz factors in range 200 < g 3000; (b) its transparency condition with emission component 10^{53-54} baryons TeV region (c) collision these circumburst medium clouds, characterized dimensions 10^{15-16} cm. addition, new...
The composition and physical state of dark matter remain among the most pressing unresolved questions in modern physics. Addressing these is crucial to our understanding Universe’s structure. In this work, we explore hypothesis that massive scalar bosons, such as axions, constitute majority matter. We focus on two key aspects axion physics: (i) role axion–neutrino coupling generating neutrino mass (ii) thermodynamic properties propose interaction between neutrinos axions early Universe,...
[Shortened] Context: [...] we point out a striking similarity between GRB 101023 and 090618. We explore the possibility that these sources are members of new family related to single core-collapse. use this understanding source in order infer unobserved redshift 101023. [...]. Aims: In precise analogy with 090618 aim analyze 89s emission see if presence two different episodes: first one presenting characteristic Black-body temperature evolution, evolving time broken power-law, second...
Context. It has been proposed that the temporal coincidence of a gamma-ray burst (GRB) and type Ib/c supernova (SN) can be explained with concept induced gravitational collapse (IGC), by matter ejected from an SN accreting onto neutron star (NS). The NS is expected to reach critical mass necessary for it black hole (BH) emit GRB. We found standard luminosity light curve behavior in late-time X-ray emission this subclass GRBs. Aims. test if GRBs become redshift estimator these sources....
Context: The induced gravitational collapse (IGC) paradigm addresses the very energetic (10^{52}-10^{54}erg) long gamma-ray bursts (GRBs) associated to supernovae (SNe). Unlike traditional "collapsar" model, an evolved FeCO core with a companion neutron star (NS) in tight binary system is considered as progenitor. This special class of sources, here named "binary driven hypernovae" (BdHNe), presents composite sequence composed four different episodes [...]. Aims: We first compare and...
Abstract We analyze the early X-ray flares in GRB “flare–plateau–afterglow” (FPA) phase observed by Swift -XRT. The FPA occurs only one of seven subclasses: binary-driven hypernovae (BdHNe). This subclass consists long GRBs with a carbon–oxygen core and neutron star (NS) binary companion as progenitors. hypercritical accretion supernova (SN) ejecta onto NS can lead to gravitational collapse into black hole. Consequently, observe emission isotropic energy <?CDATA ${E}_{\mathrm{iso}}\gtrsim...
Abstract The CALorimetric Electron Telescope primary detector (CALET-CAL) is a 30 radiation-length-deep hybrid calorimeter designed for the accurate measurement of high-energy cosmic rays. It capable triggering on and giving near complete containment electromagnetic showers from electrons gamma rays 1 GeV to over 10 TeV. first 24 months on-orbit scientific data (2015 November 01–2017 October 31) provide valuable characterization performance based analyses gamma-ray set in general bright...
We present upper limits in the hard X-ray and gamma-ray bands at time of LIGO gravitational-wave event GW 151226 derived from CALorimetric Electron Telescope (CALET) observation. The main instrument CALET, CALorimeter (CAL), observes gamma-rays ~1 GeV up to 10 TeV with a field view ~2 sr. CALET burst monitor (CGBM) views ~3 sr ~2pi sky 7 keV - 1 MeV 40 20 bands, respectively, by using two different scintillator-based instruments. CGBM covered 32.5% 49.1% localization probability...
We show the existence of two families short GRBs, both originating from merger binary neutron stars (NSs): family-1 with $E_{iso}<10^{52}$ erg, leading to a massive NS as merged core, and family-2 $E_{iso}>10^{52}$ black hole (BH). Following identification prototype GRB 090227B, we present details new example burst: 140619B. From spectral analysis early $\sim0.2$ s, infer an observed temperature $kT =(324\pm33)$ keV $e^+e^-$-plasma at transparency (P-GRB), theoretically derived redshift...
In a new classification of merging binary neutron stars (NSs) we separate short gamma-ray bursts (GRBs) in two sub-classes. The ones with $E_{iso}\lesssim10^{52}$ erg coalesce to form massive NS and are indicated as flashes (S-GRFs). hardest, $E_{iso}\gtrsim10^{52}$ erg, black hole (BH) genuine short-GRBs (S-GRBs). Within the fireshell model, S-GRBs exhibit three different components: P-GRB emission, observed at transparency self-accelerating baryon-$e^+e^-$ plasma; prompt originating from...
We present results on searches for gamma-ray counterparts of the LIGO/Virgo gravitational-wave events using CALorimetric Electron Telescope ({\sl CALET}) observations. The main instrument {\sl CALET}, CALorimeter (CAL), observes gamma-rays from $\sim1$ GeV up to 10 TeV with a field view nearly 2 sr. In addition, CALET} burst monitor (CGBM) views $\sim$3 sr and $\sim2\pi$ sky in 7 keV -- 1 MeV 40 20 bands, respectively, by two different crystal scintillators. observations International Space...
The CALorimetric Electron Telescope (CALET) is a high-energy astroparticle physics space experiment installed on the International Space Station (ISS), developed and operated by Japan in collaboration with Italy United States. CALET mission goals include investigation of possible nearby sources electrons, details galactic particle acceleration propagation, potential signatures dark matter. measures cosmic-ray electron + positron flux up to 20 TeV, gamma-rays 10 nuclei Z=1 40 1,000 TeV for...
Theoretical and observational evidences for a two-fold classification of short bursts have been recently obtained: (1) gamma-ray flashes (S-GRFs), with isotropic energy erg no black hole (BH) formation, (2) authentic (S-GRBs), showing evidence BH formation in the binary neutron star merging process. The signature is onset high-energy (0.1–100 GeV) emission, coeval to prompt all S-GRBs. No GeV emission expected nor observed S-GRFs. In this paper, we present two S-GRBs, GRB 081024B 140402A,...
Abstract At present, a variety of dark matter (DM) density profiles are available in the literature, able to fit observed rotation velocity curves galaxies. These distributions may be classified according nature and mass DM candidate, their estimation concentration on halo scales, as well through central regions. Examples these (empiric) Einasto or isotropic, (N-body-simulation-based) Navarro–Frenk–White (NFW), (elementary-particle-based) Ruffini–Argüelles–Rueda (RAR), among others. In this...
It has previously been discovered that there is a universal power law behavior exhibited by the late X-ray emission (LXRE) of "golden sample" (GS) six long energetic GRBs, when observed in rest-frame source. This remarkable feature, independent different isotropic energy (E_iso) each GRB, used to estimate cosmological redshift some GRBs. analysis extended here new class 161 all with E_iso > 10^52 erg. These GRBs are indicated as binary-driven hypernovae (BdHNe) view their progenitors: tight...
The protoMIRAX hard X-ray imaging telescope is a balloon-borne experiment developed as pathfinder for the MIRAX satellite mission. consists essentially in coded-aperture (30-200 keV) imager with square array (13$\times$13) of 2mm-thick planar CZT detectors total area 169 cm$^2$. total, fully-coded field-of-view $21^{\circ}\times 21^{\circ}$ and angular resolution 1$^{\circ}$43'. In this paper we describe instrument all subsystems its balloon gondola, show simulated results performance. main...
In this paper, we study the interaction of neutrinos with nonrelativistic axions. Axions are low-mass neutral bosons whose existence has been proposed long ago by Peccei and Quinn to explain spontaneous breaking CP symmetry in early Universe. We treat them as pseudoscalar particles, which could be one constituents cold DM. The interactions between axions might a possible mechanism for nonzero neutrino masses. Here on, present an analysis combines limits masses extracted from nonobservation...
We present the detection of a blackbody component in GRB 160107A emission by using combined spectral data CALET Gamma-ray Burst Monitor (CGBM) and MAXI Gas Slit Camera (GSC). The MAXI/GSC detected $\sim$45 s prior to main burst episode observed CGBM. CGBM spectrum this period is well fit with temperature $1.0^{+0.3}_{-0.2}$ keV plus power-law photon index $-1.6 \pm 0.3$. discuss radius photospheric based on observational properties. stress importance coordinated observations via various...
We report the results of detailed Monte Carlo simulations performance expected both at balloon altitudes and probable satellite orbit a hard X-ray coded-aperture camera being developed for Monitor e Imageador de RAios X (MIRAX) mission. Based on thorough mass model instrument specifications spectra angular dependence various relevant radiation fields stratospheric orbital environments, we have used well-known package geant4 to simulate instrumental background camera. also show simulated...