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Related papers: Optical Afterglows and IGM Attenuation

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The temporal behaviour of the early optical emission from Gamma-Ray Burst afterglows can be divided in four classes: fast-rising with an early peak, slow-rising with a late peak, flat plateaus, and rapid decays since first measurement. The…

Astrophysics · Physics 2009-11-13 A. Panaitescu , W. T. Vestrand

It has long been known that there are two classes of gamma-ray bursts (GRBs), mainly distinguished by their durations. The breakthrough in our understanding of long-duration GRBs (those lasting more than ~2 s), which ultimately linked them…

The afterglow of a gamma-ray burst (GRB) is commonly thought to be due to continuous deceleration of a relativistically expanding fireball in the surrounding medium. Assuming that the expansion of the fireball is adiabatic and that the…

Astrophysics · Physics 2009-10-30 Z. G. Dai , T. Lu

Likely progenitors for the GRBs (gamma-ray bursts) are the mergers of compact objects or the explosions of massive stars. These two cases have distinctive environments for the GRB afterglow: the compact object explosions occur in the ISM…

Astrophysics · Physics 2009-10-31 R. A. Chevalier , Z. -Y. Li

Recent observations suggest the incidence of strong intervening MgII absorption systems along the line-of-sight to gamma ray burst (GRB) afterglows is significantly higher than expected from analogous quasar sightlines. One possible…

Astrophysics · Physics 2007-09-18 Andrew Pontzen , Paul Hewett , Robert Carswell , Vivienne Wild

We use a parent sample of 118 gamma-ray burst (GRB) afterglows, with known redshift and host galaxy extinction, to separate afterglows with and without signatures of dominant reverse-shock emission and to determine which physical conditions…

High Energy Astrophysical Phenomena · Physics 2015-06-18 J. Japelj , D. Kopac , S. Kobayashi , R. Harrison , C. Guidorzi , F. J. Virgili , C. G. Mundell , A. Melandri , A. Gomboc

The detection of the delayed emission in X-ray, optical and radio band, i.e. the afterglow of $\gamma$-ray bursts (GRBs), suggestes that the sources of GRBs are likely to be at cosmological distances. Here we explore the interaction of a…

Astrophysics · Physics 2009-10-30 D. M. Wei , T. Lu

(Abridged). We present a sample of 77 optical afterglows (OAs) of Swift detected GRBs for which spectroscopic follow-up observations have been secured. We provide linelists and equivalent widths for all detected lines redward of Ly-alpha.…

Gamma-ray burst afterglows have been observed for months or even years in a few cases. It deserves noting that at such late stages, the remnants should have entered the deep Newtonian phase, during which the majority of shock-accelerated…

Astrophysics · Physics 2010-11-11 Y. F. Huang , T. Lu , K. S. Cheng

We studied the optical afterglows of the 24 pre-Swift Gamma-Ray Bursts with known spectroscopic redshift and published estimates of the optical extinction in the source frame. We find an unexpected clustering of the optical afterglow…

Astrophysics · Physics 2009-11-11 M. Nardini , G. Ghisellini , G. Ghirlanda , F. Tavecchio , C. Firmani , D. Lazzati

Gamma-ray burst astronomy has undergone a revolution in the last three years, spurred by the discovery of fading long-wavelength counterparts. We now know that at least the long duration GRBs lie at cosmological distances with estimated…

(abridged) Afterglow light curves are constructed analytically for realistic gamma-ray burst remnants decelerating in either a homogeneous interstellar medium or a stellar wind environment, taking into account the radiative loss of the…

Astrophysics · Physics 2009-11-10 X. F. Wu , Z. G. Dai , Y. F. Huang , T. Lu

Using the generic hydrodynamic model of Gamma-Ray Burst (GRB) afterglows, we calculate the radio afterglow light curves of low luminosity, high luminosity, failed and standard GRBs in different observational bands of FAST's energy window.…

High Energy Astrophysical Phenomena · Physics 2015-06-18 Zhi-Bin Zhang , Si-Wei Kong , Yong-Feng Huang , Di Li , Long-Biao Li

The afterglow emission has become the main stream of Gamma-Ray burst research since its discovery three years ago. With the distance-scale enigma solved, the study of the late-time GRB emission is now the most promising approach to disclose…

Astrophysics · Physics 2009-10-31 Luigi Piro

I review the main observational achievements concerning GRB optical afterglows occurred in the past two years. Their emission seems to be well interpreted in terms of the `fireball' model, although a variety of behaviours are observed.…

Astrophysics · Physics 2007-05-23 N. Masetti

The afterglow emission that follows gamma-ray bursts (GRBs) contains valuable information about the circumburst medium and, therefore, about the GRB progenitor. Theoretical studies of GRB blast waves, however, are often limited to simple…

High Energy Astrophysical Phenomena · Physics 2015-05-28 Petar Mimica , Dimitrios Giannios

We show that near-infrared observations of the red side of the Ly-alpha line from a single gamma ray burst (GRB) afterglow cannot be used to constrain the global neutral fraction of the intergalactic medium (IGM), x_H, at the GRB's redshift…

Astrophysics · Physics 2009-11-13 Matthew McQuinn , Adam Lidz , Matias Zaldarriaga , Lars Hernquist , Suvendra Dutta

Assuming an adiabatic evolution of a Gamma-Ray Burst (GRB) remnant interacting with an external medium, we calculate the injection, cooling, and absorption break frequencies, and the afterglow flux for plausible orderings of the break and…

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

Gamma-Ray Bursts (GRBs), short and intense pulses of low energy gamma-rays, have fascinated astronomers and astrophysicists since their unexpected discovery in the late sixties. During the last decade, several space missions: BATSE (Burst…

Astrophysics · Physics 2008-11-26 Tsvi Piran
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