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Related papers: Black-body components in Gamma-Ray Bursts spectra?

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We present the main results of a study of spectral and energetics properties of twelve gamma-ray bursts (GRBs) with redshift estimates. All GRBs in our sample were detected by BeppoSAX in a broad energy range (2-700 keV). From the redshift…

Time-resolved spectroscopy is performed on eight bright, long gamma-ray bursts (GRBs) dominated by single emission pulses that were observed with the {\it Fermi Gamma-ray Space Telescope}. Fitting the prompt radiation of GRBs by empirical…

We report results of a systematic study of the broad--band (2--2000 keV) time--resolved prompt emission spectra of a sample of Gamma-Ray Bursts (GRBs) detected with both the Wide Field Cameras (WFCs) aboard the BeppoSAX satellite and the…

High Energy Astrophysical Phenomena · Physics 2015-06-17 Filippo Frontera , Lorenzo Amati , Ruben Farinelli , Simone Dichiara , Cristiano Guidorzi , Raffaella Landi , Lev Titarchuk

Using the gamma-ray bursts simultaneously detected by Swift/BAT and Fermi/GBM we performed a joint spectral and temporal analysis of the prompt emission data and confirm the rough correlation between the BAT-band photon index Gamma_BAT and…

High Energy Astrophysical Phenomena · Physics 2015-06-03 Francisco Virgili , Ying Qin , Bing Zhang , Enwei Liang

From July 2008 to October 2009, the Gamma-ray Burst Monitor (GBM) on board the Fermi Gamma-ray Space Telescope (FGST) has detected 320 Gamma-Ray Bursts (GRBs). About 20% of these events are classified as short based on their T90 duration…

We make a detailed time resolved spectroscopy of bright long gamma ray bursts (GRBs) which show significant GeV emissions (GRB 080916C, GRB 090902B, and GRB 090926A). In addition to the standard Band model, we also use a model consisting of…

High Energy Astrophysical Phenomena · Physics 2017-02-22 A. R. Rao , Rupal Basak , J. Bhattacharya , S. Chandra , N. Maheshwari , M. Choudhury , Ranjeev Misra

The emission process responsible for the so-called "prompt" emission of gamma-ray bursts is still unknown. A number of empirical models fitting the typical spectrum still lack a satisfactory interpretation. A few GRB spectral catalogues…

High Energy Astrophysical Phenomena · Physics 2011-05-03 C. Guidorzi , M. Lacapra , F. Frontera , E. Montanari , L. Amati , F. Calura , L. Nicastro , M. Orlandini

The correlations between the rest frame peak of the EF_E spectrum of GRBs Epeak and their isotropic energy (E_iso) or luminosity (L_iso) could have several implications for the understanding of the GRB prompt emission. These correlations…

High Energy Astrophysical Phenomena · Physics 2015-05-20 Giancarlo Ghirlanda

A small fraction of gamma-ray bursts (GRBs) exhibit blackbody emission in the X-ray spectra, the origin of which is debated. In order to gain a more complete understanding of this phenomenon, we present a search for blackbody components in…

High Energy Astrophysical Phenomena · Physics 2021-01-22 Vlasta Valan , Josefin Larsson

The physical composition of the ejecta of gamma-ray bursts (GRBs) remains an open question. The radiation mechanism of the prompt gamma rays is also in debate. This problem can be solved for the bursts hosting distinct thermal radiation.…

High Energy Astrophysical Phenomena · Physics 2022-12-07 Yun Wang , Tian-Ci Zheng , Zhi-Ping Jin

We compare the spectral properties of 227 Gamma Ray Bursts (GRBs) detected by the Fermi Gamma Ray Burst Monitor (GBM) up to February 2010 with those of bursts detected by the CGRO/BATSE instrument. Out of 227 Fermi GRBs, 166 have a measured…

High Energy Astrophysical Phenomena · Physics 2010-04-12 L. Nava , G. Ghirlanda , G. Ghisellini , A. Celotti

We extend a previous work on the intrinsic spectral properties and energetics of GRBs with known redshift based on 12 BeppoSAX events by including in the sample a total of 10 more events detected either by BATSE, BeppoSAX or HETE-2. An…

Astrophysics · Physics 2014-10-13 L. Amati

We compare the spectral properties of 79 short and 79 long Gamma-Ray Bursts (GRBs) detected by BATSE and selected with the same limiting peak flux. Short GRBs have a low-energy spectral component harder and a peak energy slightly higher…

High Energy Astrophysical Phenomena · Physics 2009-11-13 G. Ghirlanda , L. Nava , G. Ghisellini , A. Celotti , C. Firmani

The prompt emission mechanism of gamma-ray bursts (GRBs) is still unclear, and the time-resolved spectral analysis of GRBs is a powerful tool for studying their underlying physical processes. We performed a detailed time-resolved spectral…

High Energy Astrophysical Phenomena · Physics 2024-01-29 Wan-Kai Wang , Wei Xie , Zhi-Fu Gao , Shuo Xiao , Ai-Jun Dong , Bin Zhang , Qi-Jun Zhi

In several gamma-ray bursts (GRBs) excess emission, in addition to the standard synchrotron afterglow spectrum, has been discovered in the early time X-ray observations. It has been proposed that this excess comes from black body emission,…

High Energy Astrophysical Phenomena · Physics 2015-03-20 M. Sparre , R. L. C. Starling

We have revisited the spectral width in the EF E spectrum of gamma-ray bursts with the BEST peak flux P and time-integrated F spectral data provided by the Fermi GBM Burst Catalog. We first compute the BEST spectral widths to compare with…

High Energy Astrophysical Phenomena · Physics 2019-08-14 Peng Zhaoyang , Zhao Xiaohong , Yin Yue , Wang Daozhou

The X-ray spectra of Gamma-Ray Bursts can generally be described by an absorbed power law. The landmark discovery of thermal X-ray emission in addition to the power law in the unusual GRB 060218, followed by a similar discovery in GRB…

High Energy Astrophysical Phenomena · Physics 2015-06-05 R. L. C. Starling , K. L. Page , A. Pe'er , A. P. Beardmore , J. P. Osborne

We perform time-resolved spectroscopy on the prompt emission in gamma-ray bursts (GRBs) and identify a thermal, photospheric component peaking at a temperature of a few hundreds keV. This peak does not necessarily coincide with the broad…

Astrophysics · Physics 2009-09-28 Felix Ryde , Asaf Pe'er

A simple test for time-asymmetry is devised and carried out on the brightest gamma-ray bursts detected by the Burst and Transient Source Experiment (BATSE) on board the {\it Compton} Gamma Ray Observatory. We show evidence that individual…

We suggest a connection between the pulse paradigm at gamma-ray energies and the recently demonstrated luminosity distribution in gamma-ray bursts: the spectral evolution timescale of pulse structures is anticorrelated with peak luminosity,…

Astrophysics · Physics 2009-10-31 J. P. Norris , G. F. Marani , J. T. Bonnell
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