F. Lucarelli
A5059250207- Astrophysics and Cosmic Phenomena
- Gamma-ray bursts and supernovae
- Particle Detector Development and Performance
- Geophysics and Gravity Measurements
- Astronomical Observations and Instrumentation
- Dark Matter and Cosmic Phenomena
- Solar and Space Plasma Dynamics
- Neutrino Physics Research
- SAS software applications and methods
- Astrophysical Phenomena and Observations
- Radio Astronomy Observations and Technology
- Pulsars and Gravitational Waves Research
- Particle Accelerators and Free-Electron Lasers
- Radiation Detection and Scintillator Technologies
- Astronomy and Astrophysical Research
- Nuclear Physics and Applications
- Particle physics theoretical and experimental studies
- Astro and Planetary Science
- Ionosphere and magnetosphere dynamics
- Atomic and Subatomic Physics Research
- Distributed and Parallel Computing Systems
- Superconducting Materials and Applications
- Medical Imaging Techniques and Applications
- Gyrotron and Vacuum Electronics Research
- Tropical and Extratropical Cyclones Research
National Institute for Astrophysics
2014-2024
Agenzia Spaziale Italiana
2015-2024
Astronomical Observatory of Rome
2015-2024
University of Perugia
2021-2023
Brera Astronomical Observatory
2021-2023
Istituto di Astrofisica Spaziale e Fisica cosmica di Palermo
2021-2023
Osservatorio di Astrofisica e Scienza dello Spazio
2023
Istituto di Astrofisica Spaziale e Fisica Cosmica di Milano
2022-2023
Osservatorio Astrofisico di Catania
2023
Taras Shevchenko National University of Kyiv
2023
Microquasars are binary star systems with relativistic radio-emitting jets. They potential sources of cosmic rays and can be used to elucidate the physics We report detection variable gamma-ray emission above 100 gigaelectron volts from microquasar LS I 61 + 303. Six orbital cycles were recorded. Several detections occur at a similar phase, which suggests that is periodic. The strongest not observed when two stars closest one another, implying strong modulation or absorption processes.
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...
The Crab supernova remnant has been observed regularly with the stereoscopic system of five imaging air Cerenkov telescopes that was part High Energy Gamma Ray Astronomy (HEGRA) experiment. In total, close to 400 hr useful data have collected from 1997 2002. differential energy spectrum combined set can be approximated by a power law-type spectrum: dΦ/dE = Φ0 Γ, 10-11 photons cm-2 s-1 TeV-1, and Γ -2.62 ± 0.02stat 0.05sys. extends up energies 80 TeV is well matched model calculations in...
232 hours of data were accumulated from 1997 to 1999, using the HEGRA Stereoscopic Cherenkov Telescope System observe supernova remnant Cassiopeia A. TeV γ-ray emission was detected at level, and a flux above 1 derived. The spectral distribution is consistent with power law differential index between 10 TeV. As this first report detection source on "centi-Crab"scale, we present analysis in some detail. Implications for acceleration cosmic rays depend details modeling. We discuss important...
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...
Recently, the Galactic center has been reported to be a source of very high energy (VHE) γ-rays by CANGAROO, VERITAS, and HESS experiments. The spectra as measured these experiments show substantial differences. In this Letter we present MAGIC observations center, resulting in detection differential γ-ray flux consistent with steady, hard-slope power law, described dNγ/(dA dt dE) = (2.9 ± 0.6) × 10-12(E/TeV)-2.2±0.2 cm-2 s-1 TeV-1. is centered at (R.A., decl.) (17h45m20s, -29°2'). This...
The ASTRI (Astrofisica con Specchi a Tecnologia Replicante Italiana) Project led by the Italian National Institute for Astrophysics (INAF) is developing and will deploy at Observatorio del Teide mini-array (ASTRI Mini-Array) composed of nine telescopes similar to small-size dual-mirror Schwarzschild-Couder telescope (ASTRI-Horn) currently operating on slopes Mt. Etna in Sicily. Mini-Array surpass current Cherenkov array differential sensitivity above few tera-electronvolt (TeV), extending...
The ASTRI Mini-Array (MA) is an INAF project to build and operate a facility study astronomical sources emitting at very high-energy in the TeV spectral band. MA consists of group nine innovative Imaging Atmospheric Cherenkov telescopes. telescopes will be installed Teide Astronomical Observatory Instituto de Astrofisica Canarias (IAC) Tenerife (Canary Islands, Spain) on basis host agreement with INAF. Thanks its expected overall performance, better than those current telescopes' arrays for...
Deep observation (~113 hrs) of the Cygnus region at TeV energies using HEGRA stereoscopic system air Čerenkov telescopes has serendipitously revealed a signal positionally inside core OB association OB2, edge 95% error circle EGRET source 3EG J2033+4118, and ~ north Cyg X-3. The centre gravity is RA : , Dec . steady, post-trial significance +4.6σ, indication for extension with radius level, differential power-law flux hard photon index integral above 1 amounts ~3% that Crab. No counterpart...
For the first time an excess of photons above energy threshold 730 GeV from giant radio galaxy M87 has been measured at a significance level 4 sigma. The data have taken during years 1998 and 1999 with HEGRA stereoscopic system 5 imaging atmospheric Cherenkov telescopes. 107.4 +- 26.8 events corresponds to integral flux 3.3% Crab or N_gamma(E > GeV) = (0.96 0.23) * 10^(-12) phot.cm^(-2)s^(-1). is located center Virgo cluster galaxies relatively small redshift z 0.00436 promising candidate...
The nearby BL Lacertae (BL Lac) object Markarian 421 (Mkn 421) at a red shift was observed to undergo strong TeV γ-ray outbursts in the observational periods from December 1999 until May 2001. time averaged flux level 1999/2000 season 10-11 ph cm-2 s-1, whereas 2000/2001 average integral increased s-1. Both energy spectra are curved and well fit by power law with an exponential cut-off TeV. respective over each of two indicate spectral hardening for spectrum. photon index changes 2000/2001....
The unidentified TeV source in Cygnus is now confirmed by follow-up observations from 2002 with the HEGRA stereoscopic system of Cherenkov Telescopes. Using all data (1999 to 2002) we confirm this new as steady flux over four years taking, extended radius 6.2 arcmin (+-1.2 (stat) +-0.9 (sys)) and exhibiting a hard spectrum photon index -1.9. It located direction dense OB stellar association, OB2. Its integral above energies E>1 amounts \~5% Crab assuming Gaussian profile for intrinsic...
Since 2005, the blazar 3C 454.3 has shown remarkable flaring activity at all frequencies, and during last four years it exhibited more than one γ-ray flare per year, becoming most active in sky. We present for first time multi-wavelength AGILE, Swift, INTEGRAL, GASP-WEBT data collected order to explain extraordinary of which occurred 2010 November. On November 20 (MJD 55520), reached a peak flux (E >100 MeV) Fpγ = (6.8 ± 1.0) × 10−5 photons cm−2 s−1 on timescale about 12 hr, factor six...
The Crab Nebula has been observed by the HEGRA (High-Energy Gamma-Ray Astronomy) stereoscopic system of imaging air Cerenkov telescopes (IACTs) for a total ~200 hr during two observational campaigns: from 1997 September to 1998 March and August 1999 April. recent detailed studies performance give an energy threshold resolution γ-rays 500 GeV ~18%, respectively. spectrum was measured with IACT in very broad range up 20 TeV, using observations at zenith angles 65°. data can be fitted 1 TeV...
The detection of TeV γ-rays from the blazar H 1426+428 at an integral flux level above 1 with HEGRA imaging atmospheric Cherenkov telescope system is reported. located a redshift 0.129, which makes it most distant source detected in so far. radiation expected to be strongly absorbed by diffuse extragalactic background (DEBRA). observed energy spectrum photons good agreement intrinsic power law corrected for DEBRA absorption. Statistical errors as well uncertainties about spectrum, however,...
The MAGIC collaboration has studied the high-frequency-peaked BL Lac object 1ES 1218+30.4, at a redshift z = 0.182, using imaging air Cerenkov telescope located on Canary Island of La Palma. A gamma-ray signal was observed with 6.4 σ significance. differential energy spectrum for an threshold 120 GeV can be fitted by simple power law, yielding FE(E) (8.1 ± 2.1) × 10-7[E/(250 GeV)]-3.0±0.4 TeV-1 m-2 s-1. During 6 days observation in 2005 January, no time variability timescales found within...
We report on the extremely intense and fast gamma-ray are above 100 MeV detected by AGILE from Crab Nebula in mid-April 2011. This event is fourth of a sequence reported major flares produced period 2007/mid-2011. These events attributed to strong radiative plasma instabilities inner Nebula, their properties crucial for theoretical studies efficient particle acceleration up 10^15 eV. Here we study very rapid flux spectral evolution that reached April 16, 2011 record-high peak F = (26 +/- 5)...
ABSTRACT We report the results of an extensive search through AGILE data for a gamma-ray counterpart to LIGO gravitational-wave (GW) event GW150914. Currently in spinning mode, has potential cover 80% sky with its instrument, more than 100 times day. It turns out that came within minute time observing accessible GW150914 localization region. Interestingly, detector exposed ∼65% this region during s intervals centered at −100 and +300 from time. determine 2 σ flux upper limit band 50 MeV–10...
We report on the first detection of very high-energy (VHE) gamma-ray emission from Crab Nebula by a Cherenkov telescope in dual-mirror Schwarzschild-Couder (SC) configuration. The result has been achieved means 4 m size ASTRI-Horn telescope, operated Mt. Etna (Italy) and developed context Telescope Array Observatory preparatory phase. SC design is aplanatic characterized small plate scale, allowing us to implement large field view cameras with small-size pixel sensors high compactness....
Fast radio bursts (FRBs) are short (millisecond) pulses originating from enigmatic sources at extragalactic distances so far lacking a detection in other energy bands. Magnetized neutron stars (magnetars) have been considered as the powering FRBs, but connection is controversial because of differing energetics and lack X-ray detections with similar characteristics two classes. We report here by AGILE satellite on April 28, 2020 an burst coincidence very bright Galactic magnetar SGR...
Abstract Gamma-ray emission in the MeV–GeV range from explosive cosmic events is of invaluable relevance to understanding physical processes related formation neutron stars and black holes. Here we report on detection by AGILE satellite energy remarkable long-duration gamma-ray burst GRB 221009A. The onboard detectors have good exposure 221009A during its initial crucial phases. Hard X-ray/MeV prompt phase lasted hundreds seconds, with brightest radiation being emitted between 200 300 s...