L. Nicastro
A5084496063- Gamma-ray bursts and supernovae
- Astronomy and Astrophysical Research
- Pulsars and Gravitational Waves Research
- Astronomical Observations and Instrumentation
- SAS software applications and methods
- Astrophysical Phenomena and Observations
- Astro and Planetary Science
- Stellar, planetary, and galactic studies
- Astrophysics and Cosmic Phenomena
- Particle Detector Development and Performance
- Geophysics and Gravity Measurements
- Radio Astronomy Observations and Technology
- Nuclear Physics and Applications
- CCD and CMOS Imaging Sensors
- Adaptive optics and wavefront sensing
- High-pressure geophysics and materials
- Calibration and Measurement Techniques
- Solar and Space Plasma Dynamics
- Galaxies: Formation, Evolution, Phenomena
- Spectroscopy and Chemometric Analyses
- Dark Matter and Cosmic Phenomena
- Scientific Research and Discoveries
- Geomagnetism and Paleomagnetism Studies
- Distributed and Parallel Computing Systems
- Spacecraft Design and Technology
National Institute for Astrophysics
2010-2024
Osservatorio di Astrofisica e Scienza dello Spazio
2018-2024
Istituto di Astrofisica Spaziale e Fisica Cosmica di Bologna
2008-2024
Max Planck Society
2018
Polish Academy of Sciences
2018
Centrum Badań Kosmicznych
2018
Osservatorio astronomico di Bologna
2017
Institute for Space Astrophysics and Planetology
2006-2016
Authorised Association Consortium
2015
Campbell Collaboration
2015
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....
BeppoSAX/PDS experiment is one of four narrow field instruments the BeppoSAX payload, that also includes two wide cameras. The goal PDS to extend energy range hard X–rays. operative 15 300 keV, where can perform sensitive spectral and temporal studies celestial sources. detector composed 4 actively shielded NaI(Tl)/CsI(Na) phoswich scintillators with a total geometric area view 13 (FWHM). In this paper we describe design discuss its functional performance calibration data analysis system.
Gamma-ray burst (GRB) emission is believed to originate in highly relativistic fireballs. Currently, only lower limits were securely set the initial fireball Lorentz factor Gamma_0. We aim provide a direct measure of The early-time afterglow light curve carries information about Gamma_0, which determines time peak. have obtained early observations near-infrared afterglows GRB 060418 and 060607A with REM robotic telescope. For both events, peak could be clearly singled out, allowing firm...
A survey of the entire southern sky for millisecond and other low-luminosity pulsars using parkes radio telescope is described. Duai linear polarization receivers are used, each centred at 436 MHz, with a 256-channel filterbank system covering bandwidth 32 MHz. Observations made beam on an approximately hexagonal grid 44 299 positions, observation time 157.3 s per pointing. The data sampled 300-μs intervals recorded magnetic tape. Off-line analyses carried out networked work-stations involve...
Multi-messenger astronomy received a great boost following the discovery of kilonova AT2017gfo, optical counterpart gravitational wave source GW170817 associated with short gamma-ray burst GRB 170817A. AT2017gfo was first that could be extensively monitored in time both photometrically and spectroscopically. Previously, only few candidates have been observed against glare afterglows. In this work, we aim to search fingerprints AT2017gfo-like emissions optical/NIR light curves 39 GRBs known...
A survey of the entire southern sky for millisecond and low-luminosity pulsars using ATNF Parkes radio telescope has now been completed. The detected 298 pulsars, which 101 were previously unknown. new include 17 pulsars. This is largest sample both normal in any survey. Combining our with other recent surveys Northern Hemisphere, we present a statistical study populations We find that improved statistics allow us to estimate number birth-rate types pulsar down 400-MHz luminosity limit 1 mJy...
We report the discovery of a transient equivalent hydrogen column density with an absorption edge at approximately 3.8 kiloelectron volts in spectrum prompt x-ray emission gamma-ray burst (GRB) 990705. This feature can be satisfactorily modeled photoelectric by medium located redshift 0.86 and iron abundance 75 times solar one. The behavior is attributed to strong ionization produced circumburst GRB photons. high points existence environment enriched supernova along line sight. explosion...
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...
We report the detection (3 sigma significance level) of a strong iron emission line in X-ray spectrum afterglow GRB 000214 (``Valentine's Day Burst'') observed by BeppoSAX. An feature was with centroid energy 4.7+/-0.2 keV which, if interpreted as K-alpha from hydrogen-like iron, corresponds to redshift z=0.47. The intensity (EW ~2 keV) and duration (tens hours) give information on distance, burst region, emitting material (R>3x10^15 cm) its mass (M>1.4 solar mass). These results are not...
We present QSFit, a new software package to automatically perform the analysis of Active Galactic Nuclei (AGN) optical spectra. The provides luminosity estimates for AGN continuum, Balmer both and UV iron blended complex, host galaxy emission lines, as well width, velocity offset equivalent width 20 lines. Improving on number previous studies spectral analysis, QSFit fits all components simultaneously, using an continuum model which extends over entire available spectrum, is thus probe...
We present BeppoSAX follow-up observations of GRB 980425 obtained with the Narrow Field Instruments (NFI) in 1998 April, May, and November. The first NFI observation has detected within 8' radius error box gamma-ray burst (GRB) an X-ray source positionally consistent supernova 1998bw, which exploded a day 980425, fainter source, not position supernova. former is following pointings exhibits decline factor 2 six months. If it associated SN this detection emission from Type I above keV. latter...
We report here on radio timing observations of the 47-ms pulsar PSR B1259–63 (PSR J1302–6350) and optical its binary companion Be star, SS 2883. The two are in a highly eccentric orbit period 3.4 yr. Radio over 1250 days with Parkes telescope now permit phase-connected solution, which shows that' next periastron is expected to occur 1994 January 9.2 ut, that has derivative |$2.3 \times 10^{-15}$|. thus characteristic age 0.33 Myr surface magnetic field strength |$3 10^{11} \ {\rm G}$|....
Following a BeppoSAX alert and the discovery of OT at SAAO, we observed GRB 990510 with FORS instrument on ESO's VLT Unit 1 (Antu). The burst is unremarkable in gamma rays, but optical first one to show good evidence for jetlike outflow. We report detection significant linear polarization afterglow: it 1.6 ± 0.2% 0.86 days after trigger, 1.81 consistent that same value, much more uncertain. angle constant timescale hours may be over day. conclude intrinsic source due synchrotron nature...
In this paper we present BeppoSAX and XMM-Newton observations of two long gamma-ray bursts (GRBs), the X-ray-rich event 2001 December 11 (GRB 011211) hard very bright November 21 011121). both events find evidence a late X-ray burst taking place several minutes after prompt emission. spectrum is much softer than that preceding phase consistent with afterglow at 1 day. addition, tail light curve day are connected by single power law ≈(t - t0), when t0 corresponds onset burst. These evidences...