A5065913565- Gamma-ray bursts and supernovae
- Astrophysics and Cosmic Phenomena
- Astrophysical Phenomena and Observations
- Particle Detector Development and Performance
- Pulsars and Gravitational Waves Research
- Astronomical Observations and Instrumentation
- Geophysics and Gravity Measurements
- Dark Matter and Cosmic Phenomena
- Solar and Space Plasma Dynamics
- SAS software applications and methods
- Nuclear Physics and Applications
- Radio Astronomy Observations and Technology
- Particle Accelerators and Free-Electron Lasers
- Astronomy and Astrophysical Research
- Neutrino Physics Research
- Astro and Planetary Science
- Ionosphere and magnetosphere dynamics
- Lightning and Electromagnetic Phenomena
- High-pressure geophysics and materials
- Particle physics theoretical and experimental studies
- Radiation Detection and Scintillator Technologies
- Stellar, planetary, and galactic studies
- Superconducting Materials and Applications
- Earthquake Detection and Analysis
- Mechanics and Biomechanics Studies
National Institute for Astrophysics
2015-2024
University of Rome Tor Vergata
2015-2024
Accademia Nazionale dei Lincei
2017-2023
Institute for Space Astrophysics and Planetology
2011-2023
Gran Sasso Science Institute
2014-2023
University of Alabama
2023
Friedrich-Alexander-Universität Erlangen-Nürnberg
2023
Consorzio Interuniversitario Fisica Spaziale
2002-2021
Istituto Nazionale di Fisica Nucleare
2011-2021
Istituto Nazionale di Fisica Nucleare, Sezione di Roma I
2006-2021
We present the main results of a study spectral and energetics properties twelve gamma-ray bursts (GRBs) with redshift estimates. All GRBs in our sample were detected by BeppoSAX broad energy range (2–700 ). From estimates good-quality time–integrated spectra we deduce their cosmological rest frames. are satisfactorily represented Band model, no significant soft X–ray excesses or absorptions. find positive correlation between estimated total (isotropic) energies 1–10 000 (Erad) redshifts z....
<i>Context. <i/> AGILE is an Italian Space Agency mission dedicated to observing the gamma-ray Universe. The AGILE's very innovative instrumentation for first time combines a imager (sensitive in energy range 30 MeV–50 GeV), hard X-ray 18–60 keV), calorimeter 350 keV–100 MeV), and anticoincidence system. was successfully launched on 2007 April 23 from Indian base of Sriharikota inserted equatorial orbit with low particle background.<i>Aims. <i/>AGILE provides crucial data study active...
The well known Crab Nebula is at the center of SN1054 supernova remnant. It consists a rotationally-powered pulsar interacting with surrounding nebula through relativistic particle wind. emissions originating from and have been considered to be essentially stable. Here we report detection strong gamma-ray (100 MeV-10 GeV) flares observed by AGILE satellite in September, 2010 October, 2007. In both cases, unpulsed flux increased factor 3 compared non-flaring flux. flare luminosity short...
We report the detection by Astrorivelatore Gamma a Immagini Leggero (AGILE) satellite of terrestrial gamma ray flashes (TGFs) obtained with minicalorimeter (MCAL) detector operating in energy range 0.3–100 MeV. select events typically lasting few milliseconds spectral and directional selections consistent TGF characteristics previously reported other space missions. During period 1 June 2008 to 31 March 2009 we detect 34 high‐confidence showing millisecond durations geographical distribution...
We present the AGILE gamma-ray observations in energy range 50 MeV - 10 GeV of supernova remnant (SNR) W44, one most interesting systems for studying cosmic-ray production. W44 is an intermediate-age SNR (20, 000 years) and its ejecta expand a dense medium as shown by prominent radio shell, nearby molecular clouds, bright [SII] emitting regions. extend our analysis to energies substantially lower than previous measurements which could not conclusively establish nature radiation. find that...
view Abstract Citations (209) References (48) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS A Shock Emission Model for Gamma-Ray Bursts. II. Spectral Properties Tavani, M. We discuss a simple model of high-energy emission gamma-ray bursts (GRBs) based on synchrotron radiation particles impulsively accelerated. The assumes source magneto- hydrodynamical outflow and efficient fast particle acceleration (most likely medIated by relativistic shock) in optically...
view Abstract Citations (243) References (27) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Accretion Turnoff and Rapid Evaporation of Very Light Secondaries in Low-Mass X-Ray Binaries Ruderman, M. ; Shaham, J. Tavani, The illumination companion stars very low mass X-ray binaries by various kinds radiation from the neighborhood neutron star after accretion has terminated or during is considered. If a star's spun-up period approaches 0.001 s, pulsar kHz can...
Strong electric discharges associated with thunderstorms can produce terrestrial gamma-ray flashes (TGFs), i.e., intense bursts of x rays and $\ensuremath{\gamma}$ lasting a few milliseconds or less. We present in this Letter new TGF timing spectral data based on the observations Italian Space Agency AGILE satellite. determine that emission above 10 MeV has significant power-law component reaching energies up to 100 MeV. These results challenge theoretical models runaway electron...
We study the physical processes of PSR B1259-63 system containing a 47 ms pulsar orbiting around Be star in highly eccentric orbit. Motivated by results multiwavelength campaign during January 1994 periastron passage B1259-63, we discuss several issues regarding mechanism high-energy emission. Unpulsed power law emission from this was detected near energy range 1-200 keV. find that observed high is not compatible with accretion or propeller-powered Shock-powered produced pulsar/outflow...
We investigated the spectral evolution in 2-700 keV energy band of gamma-ray bursts (GRBs) detected by Gamma-Ray Burst Monitor (GRBM) and localized with Wide Field Cameras (WFCs) aboard BeppoSAX satellite before 1998 May. Most them have been followed up Narrow Instruments same satellite. In light these results we discuss open issues on GRB phenomenon. find that optically thin synchrotron shock model (SSM) provides an acceptable representation most time-resolved spectra extending down to 2...
view Abstract Citations (140) References (33) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS High-Energy Emission from the Eclipsing Millisecond Pulsar PSR 1957+20 Arons, Jonathan ; Tavani, Marco The properties of high-energy emission expected eclipsing millisecond pulsar system are investigated. is considered by both relativistic shock produced wind in nebula surrounding binary and constraining mass outflow companion star 1957+20. On basis results...
The Supernova Remnant (SNR) IC 443 is an intermediate-age remnant well known for its radio, optical, X-ray and gamma-ray energy emissions. In this Letter we study the emission above 100 MeV from as obtained by AGILE satellite. A distinct pattern of diffuse in range MeV-3 GeV detected across SNR with prominent maximum (source "A") localized Northeastern shell a flux F = (47 \pm 10) 10^{-8} photons cm^{-2} s^{-1} MeV. This location site strongest shock interaction between blast wave dense...
Aims. Since the CGRO operation in 1991–2000, one of primary unresolved questions about blazar γ-ray emission has been its possible correlation with low-energy (in particular optical) emission. To help answer this problem, Whole Earth Blazar Telescope (WEBT) consortium organized GLAST-AGILE Support Program (GASP) to provide optical-to-radio monitoring data be compared detections by AGILE and GLAST satellites. This new WEBT project started early September 2007, just before a strong detection...
We present the first catalog of high-confidence <i>γ<i/>-ray sources detected by AGILE satellite during observations performed from July 9, 2007 to June 30, 2008. Cataloged were merging all available data over entire time period. AGILE, launched in April 2007, is an ASI mission devoted 30 MeV–50 GeV energy range, with simultaneous X-ray imaging capability 18–60 keV band. This based on Gamma-Ray Imaging Detector (GRID) for energies greater than 100 MeV. For catalog, we adopted a conservative...