Description of plasma focus current sheath as the Turner relaxed state of a Hall magnetofluid

Journal Article · Tue Dec 15 04:00:00 EST 2009 · Physics of Plasmas

DOI:https://doi.org/10.1063/1.3270112· OSTI ID:21371246

Auluck, S K. H. ^[1]

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1. Advanced Technology Systems Section, Bhabha Atomic Research Centre, Mumbai 400085 (India)

The central mystery of plasma focus research is the two orders-of-magnitude-higher-than-thermal fusion reaction rate and the fact that both the space-resolved neutron spectra and space-resolved reaction proton spectra show features which can be ascribed only to a rotational motion of the center-of-mass of the reacting deuteron population. It has been suggested earlier [S. K. H. Auluck, IEEE Trans. Plasma Sci. 25, 37 (1997)] that this and other experimental observations can be consistently explained in terms of a hypothesis involving rotation of the current carrying plasma annulus behind the imploding gas-dynamic shock. Such rotation (more generally, mass flow) is an in-built feature of relaxed state of a two-fluid plasma [R. N. Sudan, Phys. Rev. Lett. 42, 1277 (1979)]. Relaxation in the 'Hall magnetofluid' approximation, in which the generalized Ohm's law includes the Hall effect term and the magnetic convection term but omits the contributions to the electric field from resistive dissipation, electron pressure gradient, thermoelectric effect, electron inertia, etc., has been extensively studied by many authors. In the present paper, Turner's [IEEE Trans. Plasma Sci. PS-14, 849 (1986)] degenerate solution for the relaxed state of the Hall magnetohydrodynamic plasma has been adapted to the case of an infinitely long annular current carrying plasma, a tractable idealization of the current sheath of a plasma focus. The resulting model is consistent with experimental values of ion kinetic energy and observation of predominantly radially directed neutron emission in good shots.

• OSTI ID: 21371246
• Journal Information: Physics of Plasmas, Journal Name: Physics of Plasmas Journal Issue: 12 Vol. 16; ISSN PHPAEN; ISSN 1070-664X
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
ELECTRONS
ELEMENTARY PARTICLES
EMISSION
FERMIONS
HALL EFFECT
LEPTONS
NEUTRON EMISSION
NEUTRON SPECTRA
PLASMA FOCUS
PLASMA SHEATH
PRESSURE GRADIENTS
PROTON SPECTRA
SPECTRA