R. Desiante
A5023484442- Astrophysics and Cosmic Phenomena
- Gamma-ray bursts and supernovae
- Dark Matter and Cosmic Phenomena
- Particle Detector Development and Performance
- Radio Astronomy Observations and Technology
- Pulsars and Gravitational Waves Research
- Astrophysical Phenomena and Observations
- Astronomy and Astrophysical Research
- Astronomical Observations and Instrumentation
- Solar and Space Plasma Dynamics
- Particle physics theoretical and experimental studies
- SAS software applications and methods
- Neutrino Physics Research
- Astro and Planetary Science
- Law, AI, and Intellectual Property
- Galaxies: Formation, Evolution, Phenomena
- Ethics and Social Impacts of AI
- Stellar, planetary, and galactic studies
- Geophysics and Gravity Measurements
- Cosmology and Gravitation Theories
- Radiation Detection and Scintillator Technologies
- Intellectual Property and Patents
- Calibration and Measurement Techniques
- Particle Accelerators and Free-Electron Lasers
- Regulation and Compliance Studies
Intesa Sanpaolo (Italy)
2024
Istituto Nazionale di Fisica Nucleare, Sezione di Torino
2015-2021
University of Udine
2014-2018
University of Trieste
2012-2018
Physical Research Laboratory
2017
Centro Brasileiro de Pesquisas Físicas
2017
University of Maryland, College Park
2017
Istituto Nazionale di Fisica Nucleare, Sezione di Trieste
2012-2016
University of Amsterdam
2016
Authorised Association Consortium
2015
We present the third Fermi Large Area Telescope (LAT) source catalog (3FGL) of sources in 100 MeV–300 GeV range. Based on first 4 yr science data from Gamma-ray Space mission, it is deepest yet this energy Relative to Second LAT catalog, 3FGL incorporates twice as much data, well a number analysis improvements, including improved calibrations at event reconstruction level, an updated model for Galactic diffuse γ-ray emission, refined procedure detection, and methods associating with...
The dwarf spheroidal satellite galaxies (dSphs) of the Milky Way are some most dark matter (DM) dominated objects known. We report on gamma-ray observations dSphs based 6 years Fermi Large Area Telescope data processed with new Pass 8 event-level analysis. None significantly detected in gamma rays, and we present upper limits DM annihilation cross section from a combined analysis 15 dSphs. These constraints among strongest robust to date lie below canonical thermal relic for mass $\lesssim$...
The third catalog of active galactic nuclei (AGNs) detected by the Fermi-LAT (3LAC) is presented. It based on (3FGL) sources between 100 MeV and 300 GeV with a Test Statistic (TS) greater than 25, 2008 August 4 2012 July 31. 3LAC includes 1591 AGNs located at high Galactic latitudes (|b|>10{\deg}), 71% increase over second 2 years data. There are 28 duplicate associations, thus 1563 2192 high-latitude gamma-ray 3FGL AGNs. Most them (98%) blazars. About half newly blazars unknown type, i.e.,...
The Fermi Large Area Telescope (LAT) has provided the most detailed view to date of emission towards Galactic centre (GC) in high-energy gamma-rays. This paper describes analysis data taken during first 62 months mission energy range 1-100 GeV from a $15^\circ \times 15^\circ$ region about direction GC, and implications for interstellar emissions produced by cosmic ray (CR) particles interacting with gas radiation fields inner Galaxy point sources detected. Specialised models (IEMs) are...
Abstract The region around the Galactic Center (GC) is now well established to be brighter at energies of a few GeV than what expected from conventional models diffuse gamma-ray emission and catalogs known sources. We study excess using 6.5 yr data Fermi Large Area Telescope. characterize uncertainty GC spectrum morphology due uncertainties in cosmic-ray source distributions propagation, distribution interstellar gas Milky Way, potential contribution bubbles. also evaluate properties...
Dark matter in the Milky Way may annihilate directly into gamma rays, producing a monoenergetic spectral line. Therefore, detecting such signature would be strong evidence for dark annihilation or decay. We search lines Fermi Large Area Telescope observations of halo energy range 200 MeV to 500 GeV using analysis methods from our most recent line searches. The main improvements relative previous works are use 5.8 years data reprocessed with Pass 8 event-level and additional resulting...
We present a catalog of sources detected above 10 GeV by the Fermi Large Area Telescope (LAT) in first 7 years data using Pass 8 event-level analysis. This is Third Catalog Hard Fermi-LAT Sources (3FHL), containing 1556 objects characterized - 2 TeV energy range. The sensitivity and angular resolution are improved factors 3 relative to previous LAT at same energies (1FHL). vast majority (79%) associated with extragalactic counterparts other wavelengths, including 16 located very high...
In three years of observations since the beginning nominal science operations in August 2008, Large Area Telescope (LAT) on board Fermi Gamma Ray Space has observed high-energy (>20 MeV) \gamma-ray emission from 35 gamma-ray bursts (GRBs). Among these, 28 GRBs have been detected above 100 MeV and 7 ~ 20 MeV. The first Fermi-LAT catalog is a compilation these detections provides systematic study for time. To generate catalog, we examined 733 by Gamma-Ray Burst Monitor (GBM) processed each...
We present a catalog of sources detected above 50 GeV by the {\it Fermi}-Large Area Telescope (LAT) in 80 months data. The newly delivered Pass 8 event-level analysis allows detection and characterization GeV--2 TeV energy range. In this band, Fermi}-LAT has 360 sources, which constitute second hard (2FHL). improved angular resolution enables precise localization point ($\sim$1.7$'$ radius at 68 % C.~L.) spatially extended sources. find that 86 can be associated with counterparts other...
The observations of the exceptionally bright gamma-ray burst (GRB) 130427A by Large Area Telescope aboard Fermi Gamma-ray Space provide constraints on nature these unique astrophysical sources. GRB had largest fluence, highest-energy photon (95 GeV), longest γ-ray duration (20 hours), and one isotropic energy releases ever observed from a GRB. Temporal spectral analyses challenge widely accepted model that nonthermal high-energy emission in afterglow phase GRBs is synchrotron radiated...
ABSTRACT Most of the celestial γ rays detected by Large Area Telescope (LAT) on board Fermi Gamma-ray Space originate from interstellar medium when energetic cosmic interact with nucleons and photons. Conventional point-source extended-source studies rely modeling this diffuse emission for accurate characterization. Here, we describe development Galactic Interstellar Emission Model (GIEM), which is standard adopted LAT Collaboration publicly available. This model based a linear combination...
On 2015 June 16, Fermi-LAT observed a giant outburst from the flat spectrum radio quasar 3C 279 with peak $>100$ MeV flux of $\sim3.6\times10^{-5}\;{\rm photons}\;{\rm cm}^{-2}\;{\rm s}^{-1}$ averaged over orbital period intervals. It is historically highest $\gamma$-ray source including past EGRET observations, isotropic luminosity reaching $\sim10^{49}\;{\rm erg}\;{\rm s}^{-1}$. During outburst, Fermi spacecraft, which has an 95.4 min, was operated in special pointing mode to optimize...
We report on the search for spectral irregularities induced by oscillations between photons and axionlike-particles (ALPs) in γ-ray spectrum of NGC 1275, central galaxy Perseus cluster. Using 6 years Fermi Large Area Telescope data, we find no evidence ALPs exclude couplings above 5×10^{-12} GeV^{-1} ALP masses 0.5≲m_{a}≲5 neV at 95% confidence. The limits are competitive with sensitivity planned laboratory experiments, and, together other bounds, strongly constrain possibility that can...
Abstract The Large Area Telescope (LAT) aboard the Fermi spacecraft routinely observes high-energy emission from gamma-ray bursts (GRBs). Here we present second catalog of LAT-detected GRBs, covering first 10 yr operations, 2008 to 2018 August 4. A total 186 GRBs are found; these, 91 show in range 30–100 MeV (17 which seen only this band) and 169 detected above 100 MeV. Most these sources were discovered by other instruments ( /GBM, Swift /BAT, AGILE, INTEGRAL ) or reported Interplanetary...
We present a catalog of gamma-ray sources at energies above 10 GeV based on data from the Large Area Telescope (LAT) accumulated during first three years Fermi Gamma-ray Space mission. The Fermi-LAT >10GeV (1FHL) has 514 sources. For each source we location, spectrum, measure variability, and associations with cataloged other wavelengths. found that 449 (87%) could be associated known sources, which 393 (76% 1FHL sources) are active galactic nuclei. Of 27 pulsars, find 20 (12) to have...
We present a measurement of the cosmic-ray electron+positron spectrum between 7 GeV and 2 TeV performed with almost seven years data collected Fermi Large Area Telescope. find that is well fit by broken power law break energy at about 50 GeV. Above GeV, described single spectral index $3.07 \pm 0.02 \; (\text{stat+syst}) 0.04 (\text{energy measurement})$. An exponential cutoff lower than 1.8 excluded 95\% CL.
The Fermi Large Area Telescope (LAT) Collaboration has recently released a catalog of 360 sources detected above 50 GeV (2FHL). This was obtained using 80 months data re-processed with Pass 8, the newest event-level analysis, which significantly improves acceptance and angular resolution instrument. Most 2FHL at high Galactic latitude are blazars. Using detailed Monte Carlo simulations, we measure, for first time, source count distribution, dN/dS, extragalactic γ-ray E>50 find that it is...
ABSTRACT To uniformly determine the properties of supernova remnants (SNRs) at high energies, we have developed first systematic survey energies from 1 to 100 GeV using data Fermi Large Area Telescope (LAT). Based on spatial overlap sources detected with SNRs known radio surveys, classify 30 as likely SNRs. We also report 14 marginal associations and 245 flux upper limits. A mock catalog in which positions are scrambled Galactic longitude allows us an limit 22% number candidates falsely...
The Fermi Large Area Telescope (LAT) observed two bright X-class solar flares on 2012 March 7, and detected gamma-rays up to 4 GeV. We both during the impulsive temporally-extended emission phases, with above 100 MeV lasting for approximately 20 hours. Accurate localization of gamma-ray production site(s) coincide active region from which X-ray emissions associated these originated. Our analysis >100 shows a relatively rapid monotonic decrease in flux first hour phase, much slower, almost...
We present the detections of 19 solar flares detected in high-energy gamma rays (above 100 MeV) with Fermi Large Area Telescope (LAT) during its first four years operation. Interestingly, all are associated fairly fast Coronal Mass Ejections (CMEs) and not powerful X-ray flares. then describe detailed temporal, spatial spectral characteristics two long-lasting events: 2011 March 7 flare, a moderate (M3.7) impulsive flare followed by slowly varying gamma-ray emission over 13 hours, June M2.5...
ABSTRACT We present results from γ -ray observations of the Coma cluster incorporating six years Fermi -LAT data and newly released “Pass 8” event-level analysis. Our analysis region reveals low-significance residual structures within virial radius that are too faint for a detailed investigation with current data. Using likelihood approach is free assumptions on spectral shape we derive upper limits flux expected energetic particle interactions in cluster. also consider benchmark spatial...
Abstract The Fermi Large Area Telescope (LAT) has opened the way for comparative studies of cosmic rays (CRs) and high-energy objects in Milky Way (MW) other, external, star-forming galaxies. Using 2 yr observations with LAT, Local Group galaxy M31 was detected as a marginally extended gamma-ray source, while only an upper limit been derived other nearby M33. We revisited emission direction M33 using more than 7 LAT Pass 8 data energy range <?CDATA $0.1\mbox{--}100\,\mathrm{GeV}$?> <mml:math...
The nearby Large Magellanic Cloud (LMC) provides a rare opportunity of spatially resolved view an external star-forming galaxy in gamma-rays. LMC was detected at 0.1-100GeV as extended source with CGRO/EGRET and using early observations the Fermi-LAT. emission found to correlate massive regions be particularly bright towards 30 Doradus. Studies origin transport cosmic rays (CRs) Milky Way are frequently hampered by line-of-sight confusion poor distance determination. offers complementary way...
ABSTRACT We report the Fermi Large Area Telescope (LAT) detections of high-energy (>100 MeV) γ -ray emission from two recent optically bright classical novae, V1369 Centauri 2013 and V5668 Sagittarii 2015. At early times, target-of-opportunity observations prompted by their optical discoveries provided enhanced LAT exposure that enabled onsets beginning ∼2 days after first peaks. Significant was found extending to 39–55 initial detections, with systematically fainter longer-duration...