ANGULAR DEPENDENCE OF JITTER RADIATION SPECTRA FROM SMALL-SCALE MAGNETIC TURBULENCE / Reynolds Sarah J.,Pothapragada Sriharsha,Medvedev Mikhail V. // ASTROPHYSICAL JOURNAL. - 2010. - V. 713, l. 2. - P. 764-779.

ISSN/EISSN:

0004-637X / нет данных

Type:

Article

Abstract:

Jitter radiation is produced by relativistic electrons moving in turbulent small-scale magnetic fields such as those produced by streaming Weibel-type instabilities at collisionless shocks in weakly magnetized media. Here, we present a comprehensive study of the dependence of the jitter radiation spectra on the properties of, in general, anisotropic magnetic turbulence. We have obtained that the radiation spectra do reflect, to some extent, properties of the magnetic field spatial distribution, yet the radiation field is anisotropic and sensitive to the viewing direction with respect to the field anisotropy direction. We explore the parameter space of the magnetic field distribution and its effect on the radiation spectrum. Some important results include: the presence of the harder-than-synchrotron segment below the peak frequency at some viewing angles, the presence of the high-frequency power-law tail even for a monoenergetic distribution of electrons, the dependence of the peak frequency on the field correlation length rather than the field strength, and the strong correlation of the spectral parameters with the viewing angle. In general, we have found that even relatively minor changes in the magnetic field properties can produce very significant effects upon the jitter radiation spectra. We consider these results to be important for accurate interpretation of prompt gamma-ray burst spectra and possibly other sources.

Author keywords:

gamma-ray burst: general; magnetic fields; radiation mechanisms: non-thermal; shock waves; turbulence RELATIVISTIC COLLISIONLESS SHOCKS; RAY BURST SHOCKS; PARTICLE-ACCELERATION; FIELD GENERATION; PROMPT EMISSION; EVOLUTION; SIMULATIONS; PLASMAS

DOI:

10.1088/0004-637X/713/2/764

Web of Science ID:

ISI:000276329400006

Соавторы в МНС:

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Другие поля

Поле	Значение
Month	APR 20
Publisher	IOP PUBLISHING LTD
Address	DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND
Language	English
Keywords-Plus	RELATIVISTIC COLLISIONLESS SHOCKS; RAY BURST SHOCKS; PARTICLE-ACCELERATION; FIELD GENERATION; PROMPT EMISSION; EVOLUTION; SIMULATIONS; PLASMAS
Research-Areas	Astronomy \& Astrophysics
Web-of-Science-Categories	Astronomy \& Astrophysics
Funding-Acknowledgement	NASA {[}NNX07AJ50G, NNX08AL39G]; NSF {[}AST-0708213]; DOE {[}DE-FG02-04ER54790, DE-FG02-07ER54940]
Funding-Text	This work has been supported by NASA, NSF, DOE via grants NNX07AJ50G, NNX08AL39G, AST-0708213, DE-FG02-04ER54790, and DE-FG02-07ER54940.
Number-of-Cited-References	20
Usage-Count-Since-2013	2
Journal-ISO	Astrophys. J.
Doc-Delivery-Number	578XF