Quasicollisional magneto-optic effects in collisionless plasmas with sub-Larmor-scale electromagnetic fluctuations / Keenan Brett D.,Ford Alexander L.,Medvedev Mikhail V. // PHYSICAL REVIEW E. - 2015. - V. 92, l. 5.

ISSN/EISSN:

2470-0045 / 2470-0053

Type:

Article

Abstract:

High-amplitude, chaotic or turbulent electromagnetic fluctuations are ubiquitous in high-energy-density laboratory and astrophysical plasmas, where they can be excited by various kinetic-streaming and/or anisotropy-driven instabilities, such as the Weibel instability. These fields typically exist on ``sub-Larmor scales{''}-scales smaller than the electron Larmor radius. Electrons moving through such magnetic fields undergo small-angle stochastic deflections of their pitch angles, thus establishing diffusive transport on long time scales. We show that this behavior, under certain conditions, is equivalent to Coulomb collisions in collisional plasmas. The magnetic pitch-angle diffusion coefficient, which acts as an effective ``collision{''} frequency, may be substantial in these, otherwise, collisionless environments. We show that this effect, colloquially referred to as the plasma ``quasicollisionality,{''} may radically alter the expected radiative transport properties of candidate plasmas. We argue that the modified magneto-optic effects in these plasmas provide an attractive, radiative diagnostic tool for the exploration and characterization of small-scale magnetic turbulence, as well as affect inertial confinement fusion and other laser-plasma experiments.

Author keywords:

MAGNETIC-FIELDS; THERMAL CONDUCTION; JITTER RADIATION; PROMPT EMISSION; SOLID TARGETS; LASER-PULSES; CLUSTERS; ELECTRON; GENERATION; TRANSPORT

DOI:

10.1103/PhysRevE.92.053102

Web of Science ID:

ISI:000364216400014

Соавторы в МНС:

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Другие поля

Поле	Значение
Month	NOV 6
Publisher	AMER PHYSICAL SOC
Address	ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA
Language	English
Article-Number	053102
EISSN	2470-0053
Keywords-Plus	MAGNETIC-FIELDS; THERMAL CONDUCTION; JITTER RADIATION; PROMPT EMISSION; SOLID TARGETS; LASER-PULSES; CLUSTERS; ELECTRON; GENERATION; TRANSPORT
Research-Areas	Physics
Web-of-Science-Categories	Physics, Fluids \& Plasmas; Physics, Mathematical
Author-Email	bdkeenan@ku.edu
ORCID-Numbers	Ford, Alexander/0000-0001-6805-9787
Funding-Acknowledgement	DOE {[}DE-FG02-07ER54940]; NSF {[}AST-1209665]
Funding-Text	This work was partially supported by the DOE Grant No. DE-FG02-07ER54940 and the NSF Grant No. AST-1209665.
Number-of-Cited-References	32
Usage-Count-Since-2013	1
Journal-ISO	Phys. Rev. E
Doc-Delivery-Number	CV4DO