English
Related papers

Related papers: GeV emission from Gamma-Ray Burst afterglows

200 papers

We calculate the GeV spectra of GRB afterglows produced by inverse Compton scattering of the sub-MeV emission of these objects. We improve on earlier treatments by using refined afterglow parameters and new model developments motivated by…

Astrophysics · Physics 2019-08-19 L. J. Gou , P. Meszaros

We calculate the very high energy (sub-GeV to TeV) inverse Compton emission of GRB afterglows. We argue that this emission provides a powerful test of the currently accepted afterglow model. We focus on two processes: synchrotron…

Astrophysics · Physics 2008-03-04 Yi-Zhong Fan , Tsvi Piran , Ramesh Narayan , Da-Ming Wei

The recent detection of delayed X-ray flares during the afterglow phase of gamma-ray bursts (GRBs) suggests an inner-engine origin, at radii inside the deceleration radius characterizing the beginning of the forward shock afterglow…

Astrophysics · Physics 2009-11-11 Xiang-Yu Wang , Zhuo Li , Peter Meszaros

We investigate the GeV emission from gamma-ray bursts (GRBs), using the results from the Energetic Gamma Ray Experimental Telescope (EGRET), and in view of the Gamma-ray Large Area Space Telescope (GLAST). Assuming that the conventional…

Astrophysics · Physics 2008-12-01 Shin'ichiro Ando , Ehud Nakar , Re'em Sari

Bright optical and X-ray flares have been observed in many Gamma-ray Burst (GRB) afterglows. These flares have been attributed to late activity of the central engine. In most cases the peak energy is not known and it is possible and even…

Astrophysics · Physics 2007-05-23 Yizhong Fan , Tsvi Piran

I discuss some theoretical expectations for the synchrotron emission from a relativistic blast-wave interacting with the ambient medium, as a model for GRB afterglows, and compare them with observations. An afterglow flux evolving as a…

Astrophysics · Physics 2009-06-25 A. Panaitescu

The afterglow emission from gamma-ray bursts (GRBs) is believed to originate from a relativistic blast wave driven into the circumburst medium. Although the afterglow emission from radio up to X-ray frequencies is thought to originate from…

High Energy Astrophysical Phenomena · Physics 2020-06-18 Hao Zhang , Ian Christie , Maria Petropoulou , Jesus M. Rueda-Becerril , Dimitrios Giannios

We study high-energy gamma-ray afterglow emission from gamma-ray bursts (GRBs) in the prior emission model, which is proposed to explain the plateau phase of the X-ray afterglow. This model predicts the high-energy gamma-ray emission when…

High Energy Astrophysical Phenomena · Physics 2015-04-23 Kohta Murase , Kenji Toma , Ryo Yamazaki , Shigehiro Nagataki , Kunihito Ioka

High energy emission (> tens MeV) of Gamma-Ray Bursts (GRBs) provides an important clue to understand the physical processes involved in GRBs, which may be correlated with the GRB early afterglow. A shallow decline phase has been well…

Astrophysics · Physics 2014-10-13 Da-Ming Wei , Yi-Zhong Fan

The Fermi-LAT collaboration presented the second gamma-ray burst (GRB) catalog covering its first 10 years of operations. A significant fraction of afterglow-phase light curves in this catalog cannot be explained by the closure relations of…

High Energy Astrophysical Phenomena · Physics 2021-01-06 N. Fraija , T. Laskar , S. Dichiara , P. Beniamini , R. Barniol Duran , M. G. Dainotti , R. L. Becerra

Very early observations with the Swift satellite of gamma-ray burst (GRB) afterglows reveal that the optical component is not detected in a large number of cases. This is in contrast to the bright optical flashes previously discovered in…

When a massive star explodes as a Gamma Ray Burst information about this explosion is retained in the properties of the prompt and afterglow emission. We report on new relationships between the prompt and X-ray afterglow emission of…

High Energy Astrophysical Phenomena · Physics 2015-06-15 Dirk Grupe , John A. Nousek , Peter Veres , Binbin Zhang , Neil Gehrels

We use joint observations by the Neil Gehrels Swift X-ray Telescope (XRT) and the Fermi Large Area Telescope (LAT) of gamma-ray burst (GRB) afterglows to investigate the nature of the long-lived high-energy emission observed by Fermi LAT.…

High Energy Astrophysical Phenomena · Physics 2018-08-08 The Fermi LAT Collaboration

Four years after the launch the Swift satellite the nature of the Gamma Ray Bursts (GRBs) broadband afterglow behaviour is still an open issue ad the standard external shock fireball models cannot easily explain the puzzling combined…

High Energy Astrophysical Phenomena · Physics 2009-08-05 M. Nardini , G. Ghisellini , G. Ghirlanda , A. Celotti

Gamma-ray bursts (GRBs) are short and intense emission of soft gamma-rays, which have fascinated astronomers and astrophysicists since their unexpected discovery in 1960s. The X-ray/optical/radio afterglow observations confirm the…

Astrophysics · Physics 2009-05-07 Yi-Zhong Fan , Tsvi Piran

Recent detections of gamma-ray bursts (GRBs) at TeV energies opened new prospects for investigating radiative environments and particle acceleration mechanisms under extreme conditions. In this paper, we study the afterglows of these GRBs -…

High Energy Astrophysical Phenomena · Physics 2025-11-27 L. Foffano , M. Tavani

We study the emission observed at energies greater than 100 MeV of 11 Gamma Ray Bursts (GRBs) detected by the Fermi/Large Area Telescope (LAT) until October 2009. The GeV emission has three main properties: (i) its duration is often longer…

High Energy Astrophysical Phenomena · Physics 2015-05-14 G. Ghisellini , G. Ghirlanda , L. Nava , A. Celotti

We describe our attempt to determine if gamma-ray burst (GRB) and afterglow emissions could both arise in external shocks for simple GRBs--bursts consisting of just a few peaks in their lightcurves. We calculate peak flux and peak frequency…

Astrophysics · Physics 2016-08-30 E. McMahon , P. Kumar , A. Panaitescu

A significant fraction of the energy from the $\gamma$-ray burst (GRB) jets, after powering the keV-MeV emission, forms an ultra-relativistic shock propagating into the circumburst medium. The particles in the medium accelerate through the…

High-energy gamma-ray (>GeV) emission of gamma-ray bursts (GRBs) is very important in probing the jet evolution and particle acceleration of GRBs. The observations of high-energy photons are limited except for a few very bright GRBs,…

High Energy Astrophysical Phenomena · Physics 2026-03-11 Shi Chen , Qiang Yuan , Yi-Qing Guo , Ben-Zhong Dai , He Gao , Bing Zhang
‹ Prev 1 2 3 10 Next ›