Pulsed currents carried by whistlers. VII. Helicity and transport in heat pulses
- Department of Physics and Astronomy, University of California, Los Angeles, California 90095-1547 (United States)
In a uniform magnetoplasma ({ital n}{approx_equal}10{sup 11} cm{sup {minus}3}, {ital kT}{sub {ital e}}{ge}0.5 eV, {ital B}{sub 0}{ge}15 G, 1 m {times} 2.5 m), electrons are heated locally and temporally by applying a short current pulse to a loop antenna or disk electrode. Electron magnetohydrodynamics characterize the experimental conditions. After the end of the applied current pulse and whistler wave transients, a current system driven by temperature gradients remains embedded in the plasma. The current system exhibits helicity. The associated electron drifts convect heat out of the flux tube. From diamagnetic field measurements, the decay of the electron temperature is obtained with high sensitivity ({Delta}{ital kT}{sub {ital e}}{approx_equal}0.001 eV). The heat transport is inferred from the space{endash}time dependence of the electron temperature. The temperature enhancement is confined to a channel whose length depends on heat input since the transport coefficients are temperature-dependent. {copyright} {ital 1996 American Institute of Physics.}
- OSTI ID:
- 285579
- Journal Information:
- Physics of Plasmas, Journal Name: Physics of Plasmas Journal Issue: 7 Vol. 3; ISSN PHPAEN; ISSN 1070-664X
- Country of Publication:
- United States
- Language:
- English
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