Radiative diagnostics for sub-Larmor scale magnetic turbulence / Reynolds Sarah J.,Medvedev Mikhail V. // PHYSICS OF PLASMAS. - 2012. - V. 19, l. 2.

ISSN/EISSN:

1070-664X / 1089-7674

Type:

Article

Abstract:

Radiative diagnostics of high-energy density plasmas is addressed in this paper. We propose that the radiation produced by energetic particles in small-scale magnetic field turbulence, which can occur in laser-plasma experiments, collisionless shocks, and during magnetic reconnection, can be used to deduce some properties of the turbulent magnetic field. Particles propagating through such turbulence encounter locally strong magnetic fields but over lengths much shorter than a particle gyroradius (that is lambda(B) << gamma m nu/q < B-perpendicular to >). Consequently, the particle does not gyrate but undergoes a series of transverse accelerations reflective of the magnetic field variations it encounters. In the limit of small deflection angle, the particle is accelerated but never substantially deviated from a straight line path. We develop the general jitter radiation solutions for this case and show that the resulting radiation is directly dependent upon the spectral distribution of the magnetic field through which the particle propagates. We demonstrate the power of this approach in considering the radiation produced by particles moving through a region in which a (Weibel-like) filamentation instability grows magnetic fields randomly oriented in a plane transverse to counterstreaming particle populations. We calculate the spectrum as would be seen from the original particle population and as could be seen by using a quasi-monoenergetic electron beam to probe the turbulent region at various angles to the filamentation axis. (C) 2012 American Institute of Physics. {[}doi:10.1063/1.3677827]

Author keywords:

RELATIVISTIC COLLISIONLESS SHOCKS; PARTICLE-ACCELERATION; JITTER RADIATION; FIELD GENERATION; PROMPT EMISSION; SIMULATIONS; EVOLUTION; PLASMAS

DOI:

10.1063/1.3677827

Web of Science ID:

ISI:000301395800047

Соавторы в МНС:

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Другие поля

Поле	Значение
Month	FEB
Publisher	AMER INST PHYSICS
Address	1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA
Language	English
Article-Number	023106
EISSN	1089-7674
Keywords-Plus	RELATIVISTIC COLLISIONLESS SHOCKS; PARTICLE-ACCELERATION; JITTER RADIATION; FIELD GENERATION; PROMPT EMISSION; SIMULATIONS; EVOLUTION; PLASMAS
Research-Areas	Physics
Web-of-Science-Categories	Physics, Fluids \& Plasmas
Funding-Acknowledgement	NSF {[}AST-0708213]; NASA ATFP {[}NNX-08AL39G]; DOE {[}DE-FG02-07ER5494]
Funding-Text	This work has been supported by NSF grant AST-0708213, NASA ATFP grant NNX-08AL39G, and DOE grant DE-FG02-07ER5494. We also gratefully acknowledge the computer system expertise of our colleague Sriharsha Pothapragada.
Number-of-Cited-References	18
Usage-Count-Since-2013	2
Journal-ISO	Phys. Plasmas
Doc-Delivery-Number	907CQ