Creation of Magnetic Fields by Electrostatic and Thermal Fluctuations

Journal Article · Tue Nov 10 04:00:00 EST 2009 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.3266802· OSTI ID:21335664

Saleem, Hamid ^[1]

---

1. National Centre for Physics (NCP), Quaid-i-Azam University Campus, Islamabad (Pakistan)

It is pointed out that the electrostatic and thermal fluctuations are the main source of magnetic fields in unmagnetized inhomogeneous plasmas. The unmagnetized inhomogeneous plasmas can support a low frequency electromagnetic ion wave as a normal mode like Alfven wave of magnetized plasmas. But this is a coupled mode produced by the mixing of longitudinal and transverse components of perturbed electric field due to density inhomogeneity. The ion acoustic wave does not remain electrostatic in non-uniform plasmas. On the other hand, a low frequency electrostatic wave can also exist in the pure electron plasmas and it couples with ion acoustic wave when ions are dynamic. These waves can become unstable when density and temperature gradients are parallel to each other as can be the case of laser plasmas and is the common situation in stellar cores. The main instability condition for the electrostatic and electromagnetic modes is the same (2/3){kappa}{sub n}<{kappa}{sub T}(where {kappa}{sub n} and {kappa}{sub T} are inverse of the scale lengths of gradients of density and electron temperature, respectively). This indicates that the electrostatic and magnetic field fluctuations are strongly coupled in unmagnetized nonuniform plasmas.

• OSTI ID: 21335664
• Journal Information: AIP Conference Proceedings, Journal Name: AIP Conference Proceedings Journal Issue: 1 Vol. 1188; ISSN 0094-243X; ISSN APCPCS
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
ABLATION
ALFVEN WAVES
COUPLING
ELECTRIC FIELDS
ELECTRON DENSITY
ELECTRON TEMPERATURE
ELECTRONS
FLUCTUATIONS
INHOMOGENEOUS PLASMA
ION ACOUSTIC WAVES
IONS
MAGNETIC FIELDS
MAGNETOHYDRODYNAMICS
SOUND WAVES
TEMPERATURE GRADIENTS
VORTICES