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Related papers: GeV emission from Gamma-Ray Burst afterglows

200 papers

Gamma-ray burst (GRB) afterglow emission is believed to be produced by synchrotron emission of electrons accelerated to high energy by a relativistic collisionless shock propagating into a weakly magnetized plasma. Afterglow observations…

Astrophysics · Physics 2010-11-11 Zhuo Li , Eli Waxman

We discuss the GeV to TeV photon emission of gamma-ray bursts (GRBs) within the refreshed shock and the continuous injection scenarios, motivated by the observation of extended emission in a substantial fraction of short GRBs. In the first…

High Energy Astrophysical Phenomena · Physics 2015-06-18 P. Veres , P. Mészáros

We investigate wheter there is any correlation between the X-ray afterglow luminosity and the prompt emission properties of a carefully selected sub-sample of bright Swift long Gamma-Ray Bursts (GRBs) nearly complete in redshift (~90%).…

Scattering of the forward-shock synchrotron emission by a relativistic outflow located behind the leading blast-wave may produce an X-ray emission brighter than that coming directly from the forward-shock and may explain four features…

Astrophysics · Physics 2009-11-13 A. Panaitescu

X-ray light curves of gamma-ray burst (GRB) afterglows exhibit various features, with the shallow decay phase being particularly puzzling. While some studies report absence of the X-ray shallow decay for hyper-energetic GRBs, recently…

High Energy Astrophysical Phenomena · Physics 2025-04-16 Kenta Terauchi , Tomohiko Oka , Katsuaki Asano

Gamma-ray Bursts (GRBs) are among the potential extragalactic sources of very-high-energy (VHE) gamma-rays. We discuss the prospects of detecting VHE gamma-rays with current ground-based Cherenkov instruments during the afterglow phase.…

Astrophysics · Physics 2010-11-11 P. H. Tam , R. R. Xue , S. J. Wagner , B. Behera , Y. Z. Fan , D. M. Wei

We calculate the expected spectrum and light curves of the early afterglow. For short GRBs the peak of the afterglow will be delayed, typically, by a few dozens of seconds after the burst. The x-ray and gamma-ray characteristics of this…

Astrophysics · Physics 2009-10-31 Re'em Sari , Tsvi Piran

The gamma-ray bursts (GRBs) of long duration are very likely to be connected to the death of massive stars. The gamma-ray emission is believed to come from energy released internally in a flow that moves at ultrarelativistic speed. The fast…

Astrophysics · Physics 2009-06-23 Dimitrios Giannios

The high energy emission from Gamma-ray Bursts has some interesting features, including the absence of the GeV excess in the prompt spectrum, the delayed onset of the GeV emission, and the longer duration of the GeV emission than the prompt…

Cosmology and Nongalactic Astrophysics · Physics 2010-03-16 Yi-Zhong Fan

We investigate the effect that the absorption of high-energy (above 100 MeV) photons produced in GRB afterglow shocks has on the light-curves and spectra of Fermi-LAT afterglows. Afterglows produced by the interaction of a relativistic…

High Energy Astrophysical Phenomena · Physics 2015-06-16 A. Panaitescu , W. T. Vestrand , P. Wozniak

Gamma-ray burst (GRB) afterglows are likely produced in the shock that is driven as the GRB jet interacts with the external medium. Long-duration GRBs are also associated with powerful supernovae (SNe). We consider the optical and radio…

High Energy Astrophysical Phenomena · Physics 2016-08-08 Adithan Kathirgamaraju , Rodolfo Barniol Duran , Dimitrios Giannios

(Abridged) The Swift X-Ray Telescope (XRT) reveals some interesting features of early X-ray afterglows, including a distinct rapidly decaying component preceding the conventional afterglow component in many sources, a shallow decay…

Swift discovered GRB 050713A and slewed promptly to begin observing with its narrow field instruments 72.6 seconds after the burst onset, while the prompt gamma-ray emission was still detectable in the BAT. Simultaneous emission from two…

Extensive observational campaigns of afterglow hunting have greatly enriched our understanding of the gamma-ray burst (GRB) phenomenon. Efforts have been made recently to explore some afterglow properties or signatures that will be tested…

Astrophysics · Physics 2007-05-23 Bing Zhang , Peter Meszaros , Junfeng Wang

We discuss observations of the prompt X and gamma-ray emission and X-ray afterglow from GRB981226. This event has the weakest gamma-ray peak flux detected with the Gamma-Ray Burst Monitor. It shows an isolated X-ray precursor and the…

Recently, X-ray emission lines have been observed in X-ray afterglows of several $\gamma$-ray bursts. It is a major breakthrough for understanding the nature of the progenitors. It is proposed that the X-ray emission lines can be well…

Astrophysics · Physics 2009-11-11 W. H. Gao , D. M. Wei

Gamma-ray Bursts (GRBs) generate powerful relativistic jets that inject a large amount of energy into their surrounding environment, producing blast waves that accelerate particles to high energies. The GRB afterglow radiation provides a…

High Energy Astrophysical Phenomena · Physics 2026-02-24 P. Tiwari , B. Banerjee , D. Miceli , G. Oganesyan , A. Ierardi , S. Macera , M. Branchesi , L. Nava , S. Mohnani , S. Agarwal , A. Shukla

According to current models, gamma-ray bursts (GRBs) are produced when the energy carried by a relativistic outflow is dissipated and converted into radiation. The efficiency of this process, $\epsilon_\gamma$, is one of the critical…

Astrophysics · Physics 2009-11-11 Jonathan Granot , Arieh Konigl , Tsvi Piran

Gamma-ray bursts (GRBs) show diverse X-ray afterglow light-curves, including breaks and plateaus, whose physical origins remain debated. Previous claims linked high-energy ($E \ge 100$ MeV) detection to X-ray afterglow complexity or plateau…

High Energy Astrophysical Phenomena · Physics 2026-05-27 A. A. Vigliano , F. Longo , Ž. Bošnjak

The physical origin of the >0.1 GeV emission detected from Gamma-Ray Bursts (GRBs) by the Fermi satellite has not yet been completely understood. In this work we consider the GeV light curves of ten GRBs with measured redshift detected by…

High Energy Astrophysical Phenomena · Physics 2015-06-22 L. Nava , G. Vianello , N. Omodei , G. Ghisellini , G. Ghirlanda , A. Celotti , F. Longo , R. Desiante , R. Barniol Duran