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Related papers: Classification of Fermi Gamma-RAY Bursts

200 papers

Gamma-ray bursts (GRBs) are divided into two classes according to their durations. We investigate if the softness of bursts plays a role in the conventional classification of the objects. We employ the BATSE (Burst and Transient Source…

High Energy Astrophysical Phenomena · Physics 2010-10-12 Y. -P. Qin , A. C. Gupta , J. H. Fan , C. -Y. Su , R. -J. Lu

We present an optical flux vs. X-ray flux diagram for all known gamma-ray bursts (GRBs) for which an X-ray afterglow has been detected. We propose an operational definition of dark bursts as those bursts that are optically subluminous with…

Astrophysics · Physics 2007-05-23 P. Jakobsson , J. Hjorth , J. P. U. Fynbo , D. Watson , K. Pedersen , G. Bjornsson , J. Gorosabel

Gamma-ray bursts (GRBs) are detectable out to very large distances and as such are potentially powerful cosmological probes. Historically, the angular distribution of GRBs provided important information about their origin and physical…

High Energy Astrophysical Phenomena · Physics 2015-11-11 T. N. Ukwatta , P. R. Wozniak

Gamma-ray bursts can be divided into three groups ("short", "intermediate", "long") with respect to their durations. The third type of gamma-ray bursts - as known - has the intermediate duration. We show that the intermediate group is the…

Astrophysics · Physics 2009-11-13 I. Horvath , F. Ryde , L. G. Balazs , Z. Bagoly , A. Meszaros

Gamma-ray bursts (GRBs) were confirmed to be of extragalactic origin due to their isotropic angular distribution, combined with the fact that they exhibited an intensity distribution that deviated strongly from the $-3/2$ power law. This…

High Energy Astrophysical Phenomena · Physics 2019-08-14 Mariusz Tarnopolski

The prompt emission of gamma-ray bursts remains mysterious since the mechanism is difficult to understand even though there are much more observations with the development of detection technology. But most of the gamma-ray bursts spectra…

High Energy Astrophysical Phenomena · Physics 2020-02-26 Ming-Ya Duan , Xiang-Gao Wang

Two classes of gamma-ray bursts have been identified so far, characterized by durations shorter and longer than approximately 2 seconds. In 1998 two independent papers indicated the existence of the third class of the bursts roughly…

Astrophysics · Physics 2007-05-23 I. Horvath

Recent Swift observations suggest that the traditional long vs. short GRB classification scheme does not always associate GRBs to the two physically motivated model types, i.e. Type II (massive star origin) vs. Type I (compact star origin).…

High Energy Astrophysical Phenomena · Physics 2011-04-04 Houjun Lv , Enwei Liang , Binbin Zhang , Bing Zhang

Gamma-ray bursts of short duration may harbor vital clues to the range of phenomena producing bursts. However, recent progress from the observation of optical counterparts has not benefitted the study of short bursts. We have searched for…

Using an established classification technique, we leverage standard observations and analyses to predict the progenitors of gamma-ray bursts (GRBs). This technique, utilizing support vector machine (SVM) statistics, provides a more nuanced…

High Energy Astrophysical Phenomena · Physics 2024-07-15 P. Nuessle , J. L. Racusin , N. E. White

Observations of Gamma-Ray Bursts with the Fermi Large Area Telescope have prompted theoretical advances and posed big challenges in the understanding of such extreme sources, despite the fact that GRB emission above 100 MeV is a fairly rare…

High Energy Astrophysical Phenomena · Physics 2015-02-12 Giacomo Vianello , Nicola Omodei , Fermi/LAT collaboration

Phenomenologically, two classes of GRBs (long/soft vs. short/hard) are identified based on their gamma-ray properties. The boundary between the two classes is vague. Multi-wavelength observations lead to identification of two types of GRB…

High Energy Astrophysical Phenomena · Physics 2015-06-04 Bing Zhang

We statistically examine the gamma-ray burst (GRB) photon indices obtained by the Fermi-GBM and Fermi-LAT observations and compare the LAT GRB photon indices to the GBM GRB photon indices. We apply the jitter radiation to explain the GRB…

High Energy Astrophysical Phenomena · Physics 2020-07-29 Jirong Mao , Liande Li , Jiancheng Wang

The Large Area Telescope (LAT) on-board the Fermi satellite detected emission above 20 MeV only in a small fraction of the long gamma-ray bursts (GRBs) detected by the Fermi Gamma-ray Burst Monitor (GBM) at 8 keV-40 MeV. Those bursts that…

High Energy Astrophysical Phenomena · Physics 2013-03-08 Dafne Guetta

Since its successful launch in June 2008, the {\it Fermi} Gamma-ray Space Telescope has made important breakthroughs in the understanding of the Gamma-Ray Burst (GRB) phenomemon. The combination of the GBM and the LAT instruments onboard…

High Energy Astrophysical Phenomena · Physics 2015-05-28 Frederic Piron , Valerie Connaughton

The conventional classification of Gamma-Ray Bursts (GRBs) as short or long bursts based on their duration is widely accepted as arising from different progenitor sources identified as compact object mergers and collapsars, respectively.…

High Energy Astrophysical Phenomena · Physics 2023-09-25 Dimple , Kuntal Misra , Lallan Yadav

Gamma-ray bursts (GRB) are extreme events. They are crudely classified into two groups based on their duration, namely the short and long bursts. Such a classification has proven to be useful to determine their progenitors: the merger of…

High Energy Astrophysical Phenomena · Physics 2015-03-17 Hüsne Dereli

Gamma ray bursts have been divided into two classes, long-soft gamma ray burst and short-hard gamma ray burst according to the bimodal distribution in duration time. Due to the harder spectrum and the lack of afterglows of short-hard bursts…

Astrophysics · Physics 2007-10-09 Soomin Jeong , Chang-Hwan Lee

Two types of Gamma-ray bursts (GRBs) are observed: short duration hard spectrum GRBs and long duration soft spectrum GRBs. For many years long GRBs were the focus of intense research while the lack of observational data limited the study of…

Astrophysics · Physics 2010-04-06 Ehud Nakar

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…