Jitter radiation as a possible mechanism for gamma-ray burst afterglows: Spectra and light curves / Medvedev Mikhail V.,Lazzati Davide,Morsony Brian C.,Workman Jared C. // ASTROPHYSICAL JOURNAL. - 2007. - V. 666, l. 1, 1. - P. 339-345.

ISSN/EISSN:

0004-637X / нет данных

Type:

Article

Abstract:

The standardmodel of gamma-ray burst afterglows assumes that the radiation observed as a delayed emission is of synchrotron origin, which requires the shock magnetic field to be relatively homogeneous on small scales. An alternative mechanism-jitter radiation, which traditionally has been applied to the prompt emission-substitutes for synchrotron when the magnetic field is tangled on a microscopic scale. Such are the fields produced at relativistic shocks by theWeibel instability. Here we explore the possibility that small-scale fields populate afterglow shocks. We derive the spectrum of jitter radiation under the afterglow conditions. We also derive the afterglow light curves for the interstellar medium and wind profiles of the ambient density. Jitter self-absorption is calculated here for the first time. We find that jitter radiation can produce afterglows similar to synchrotron-generated ones, but with some important differences. We compare the predictions of the two emission mechanisms. With future observational data, one may be able to discriminate between the synchrotron and jitter afterglow light curves, and, hence, between the small-scale versus large-scale magnetic field models in afterglow shocks.

Author keywords:

gamma rays : bursts; magnetic fields; shock waves MAGNETIC-FIELDS; PARTICLE-ACCELERATION; COLLISIONLESS SHOCKS; PROMPT EMISSION; GENERATION; EVOLUTION; JETS

DOI:

10.1086/520701

Web of Science ID:

ISI:000249058600032

Соавторы в МНС:

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Другие поля

Поле	Значение
Month	SEP 1
Publisher	UNIV CHICAGO PRESS
Address	1427 E 60TH ST, CHICAGO, IL 60637-2954 USA
Language	English
Keywords-Plus	MAGNETIC-FIELDS; PARTICLE-ACCELERATION; COLLISIONLESS SHOCKS; PROMPT EMISSION; GENERATION; EVOLUTION; JETS
Research-Areas	Astronomy \& Astrophysics
Web-of-Science-Categories	Astronomy \& Astrophysics
Number-of-Cited-References	23
Usage-Count-Since-2013	4
Journal-ISO	Astrophys. J.
Doc-Delivery-Number	204QH