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Related papers: Critical Review of Basic Afterglow Concepts

200 papers

Based on the early-year observations from Neil Gehrels \emph{Swift} Observatory, \cite{liang07} performed a systematic analysis for the shallow decay component of gamma-ray bursts (GRBs) X-ray afterglow, in order to explore its physical…

High Energy Astrophysical Phenomena · Physics 2019-10-02 Litao Zhao , Binbin Zhang , He Gao , Lin Lan , Houjun Lü , Bing Zhang

We present Follow-Up Network for Gamma-Ray Bursts (FUN GRB) Collaboration observations of the optical afterglow of GRB 021211 made between 143 seconds and 102 days after the burst. Our unique data set includes the earliest filtered…

Cosmological gamma-ray bursts (GRBs) and their afterglows seem to result from dissipation of bulk energy in relativistic outflows, but their engine has not been unambiguously identified. The engine could be a young pulsar formed from…

Astrophysics · Physics 2009-10-30 Eric G. Blackman , Insu Yi

Despite the enormous progress occurred in the last 10 years, the Gamma-Ray Bursts (GRB) phenomenon is still far to be fully understood. One of the most important open issues that have still to be settled is the afterglow emission above 10…

Astrophysics · Physics 2007-10-09 L. Amati , E. Maiorano , E. Palazzi , R. Landi , F. Frontera , N. Masetti , L. Nicastro

The properties of the ambient medium in which GRBs go off are an important piece of the puzzle, not only as an issue in itself, but because of their link with the nature of the progenitor. In this review, I describe and critically comment…

Astrophysics · Physics 2007-05-23 Davide Lazzati

Gamma-ray bursts (GRBs) are generally believed to occur in environments where the surrounding medium is either a uniform interstellar medium (ISM) or, in some cases, a dense stellar wind from a massive progenitor. Recently, GRB 191019A has…

High Energy Astrophysical Phenomena · Physics 2025-12-10 Xiao-Hong Zhao

Since the suggestion of relativistic shocks as the origin of gamma-ray bursts (GRBs) in early 90's, the mathematical formulation of this process has stayed at phenomenological level. One of the reasons for the slow development of…

Astrophysics · Physics 2015-05-13 Houri Ziaeepour

The follow-up of $\gamma$-ray bursts (GRBs) by the X-ray telescope (XRT, 0.3-10 keV) on board the Neil Gehrels Swift Observatory led to the discovery of a shallow decay phase (the so-called plateau) of the X-ray emission in a good fraction…

High Energy Astrophysical Phenomena · Physics 2020-06-26 Gor Oganesyan

Previously detected in only a few gamma-ray bursts (GRBs), X-ray flares are now observed in ~50% of Swift GRBs, though their origins remain unclear. Most flares are seen early on in the afterglow decay, while some bursts exhibit flares at…

Gamma-ray burst (GRB) jets are narrow, and thus typically point away from us. They are initially ultra-relativistic, causing their prompt $\gamma$-ray and early afterglow emission to be beamed away from us. However, as the jet gradually…

High Energy Astrophysical Phenomena · Physics 2018-09-19 Jonathan Granot , Fabio De Colle , Enrico Ramirez-Ruiz

In models for gamma ray burst afterglows, it is normally assumed that the external shock strongly amplifies the magnetic field and that this field maintains a steady value throughout the shocked region. We discuss the effects of modifying…

Astrophysics · Physics 2009-11-07 Elena Rossi , Martin J. Rees

The detection of delayed emission in X-ray, optical and radio wave length, ``afterglow'', following a gamma-ray burst can be described by the emission of a relativistic shell decelerating upon collision with the ISM. We show that the…

Astrophysics · Physics 2009-10-30 Re'em Sari

There have been great and rapid progresses in the field of $\gamma$-ray bursts (denoted as GRBs) since BeppoSAX and other telescopes discovered their afterglows in 1997. Here, we will first give a brief review on the observational facts of…

Astrophysics · Physics 2016-01-27 T. Lu

Based on light curves from the Swift Burst Analyser, we investigate whether a `dip' feature commonly seen in the early-time hardness ratios of Swift-XRT data could arise from the juxtaposition of the decaying prompt emission and rising…

High Energy Astrophysical Phenomena · Physics 2015-05-27 P. A. Evans , J. P. Osborne , R. Willingale , P. T. O'Brien

We examine a sample of 21 gamma-ray burst (GRB) afterglow light curves at radio frequencies, and compare them to the X-ray and/or optical properties of the afterglows and to the predictions of the standard jet/fireball model. Our sample…

High Energy Astrophysical Phenomena · Physics 2021-04-20 Tuomas Kangas , Andrew Fruchter

Gamma-ray bursts (GRBs) are believed to be powered by the electromagnetic extraction of spin energy from a black hole endowed with a magnetic field supported by electric currents in a surrounding disk (Blandford & Znajek 1977). A generic…

High Energy Astrophysical Phenomena · Physics 2015-12-16 Antonios Nathanail , Achillies Strantzalis , Ioannis Contopoulos

In the past two years, tremendous progresses to understand X-ray Flashes have been made. Now it is widely believed that X-ray Flashes and Gamma-ray Bursts are intrinsically the same, their much different peak energy and flux may be just due…

Astrophysics · Physics 2009-11-10 Y. Z. Fan , D. M. Wei , C. F. Wang

We report a multi-wavelength analysis of the prompt emission and early afterglow of GRB051111 and discuss its properties in the context of current fireball models. The detection of GRB051111 by the Burst Alert Telescope on-board Swift…

We investigate a model for the shallow decay phases of Gamma-ray Burst (GRB) afterglows discovered by Swift/XRT in the first hours following a GRB event. In the context of the fireball scenario, we consider the possibility that long-lived…

High Energy Astrophysical Phenomena · Physics 2015-05-18 Simone Dall'Osso , Giulia Stratta , Dafne Guetta , Stefano Covino , Giovanni De Cesare , Luigi Stella

Early multiwavelength observations offer crucial insights into the nature of the relativistic jets responsible for gamma-ray bursts and their interaction with the surrounding medium.We present data of GRB 240825A from 17 space- and…