Thermal fluctuation levels of magnetic and electric fields in unmagnetized plasma: The rigorous relativistic kinetic theory

Journal Article · Sat Mar 15 00:00:00 EDT 2014 · Physics of Plasmas

DOI:https://doi.org/10.1063/1.4868232· OSTI ID:22251936

Yoon, P. H., E-mail: [e-mail], E-mail: [e-mail], E-mail: [e-mail] ^[1]; School of Space Research, Kyung Hee University, Yongin-Si, Gyeonggi-Do 446-701 ^[2]; Schlickeiser, R., E-mail: [e-mail], E-mail: [e-mail], E-mail: [e-mail] ^[3]; Research Department Plasmas with Complex Interactions, Ruhr-Universität Bochum, D-44780 Bochum ^[4]; Kolberg, U., E-mail: [e-mail], E-mail: [e-mail], E-mail: [e-mail] ^[3]

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1. Institute for Physical Science and Technology, University of Maryland, College Park, Maryland 20742 (United States)
2. (Korea, Republic of)
3. Institut für Theoretische Physik, Lehrstuhl IV: Weltraum und Astrophysik, Ruhr-Universität Bochum, D-44780 Bochum (Germany)
4. (Germany)

Any fully ionized collisionless plasma with finite random particle velocities contains electric and magnetic field fluctuations. The fluctuations can be of three different types: weakly damped, weakly propagating, or aperiodic. The kinetics of these fluctuations in general unmagnetized plasmas, governed by the competition of spontaneous emission, absorption, and stimulated emission processes, is investigated, extending the well-known results for weakly damped fluctuations. The generalized Kirchhoff radiation law for both collective and noncollective fluctuations is derived, which in stationary plasmas provides the equilibrium energy densities of electromagnetic fluctuations by the ratio of the respective spontaneous emission coefficient and the true absorption coefficient. As an illustrative example, the equilibrium energy densities of aperiodic transverse collective electric and magnetic fluctuations in an isotropic thermal electron-proton plasmas of density n{sub e} are calculated as |δB|=√((δB){sup 2})=2.8(n{sub e}m{sub e}c{sup 2}){sup 1/2}g{sup 1/2}β{sub e}{sup 7/4} and |δE|=√((δE){sup 2})=3.2(n{sub e}m{sub e}c{sup 2}){sup 1/2}g{sup 1/3}β{sub e}{sup 2}, where g and β{sub e} denote the plasma parameter and the thermal electron velocity in units of the speed of light, respectively. For densities and temperatures of the reionized early intergalactic medium, |δB|=6·10{sup −18}G and |δE|=2·10{sup −16}G result.

• OSTI ID: 22251936
• Journal Information: Physics of Plasmas, Vol. 21, Issue 3; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 1070-664X
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ABSORPTION
COLLISIONLESS PLASMA
ELECTRIC FIELDS
ELECTRONS
ENERGY DENSITY
EQUILIBRIUM
FLUCTUATIONS
MAGNETIC FIELDS
PROTONS
RELATIVISTIC RANGE
STIMULATED EMISSION