Physics of Plasmas -- November 1994 -- Volume 1, Issue 11, pp. 3570-3576

Electron heat transport with non-Maxwellian distributions

J. M. Liu and J. S. De Groot

Plasma Research Group, Department of Applied Science, University of California, Davis, California 95616

J. P. Matte and T. W. Johnston

INRS-Énergie et Matériaux, C.P. 1020, Varennes, Québec, J3X 1S2 Canada

R. P. Drake

Plasma Physics Research Institute, Lawrence Livermore National Laboratory, L-418, P.O. Box 808, Livermore, California 94551

(Received 8 March 1994; accepted 14 July 1994)

Measurements are presented of electron heat transport with non-Maxwellian (flattopped) distributions due to inverse bremsstrahlung absorption of intense microwaves in the University of California at Davis Aurora II device [Rogers et al., Phys. Fluids B 1, 741 (1989)]. The plasma is created by pulsed discharge in a cylindrical vacuum chamber with surface magnets arranged to create a density gradient. The ionization fraction (~1%) is high enough that charged particle collisions are strongly dominant in the afterglow plasma. A short microwave pulse (~2 µs) heats a region of the afterglow plasma (n_e/n_cr0.5) creating a steep axial (L_T~1–10_ei) temperature gradient. Langmuir probes are used to measure the relaxation of the heat front after the microwave pulse. Time and space resolved measurements show that the isotropic component of the electron velocity distribution is flat topped (~exp[–(v/v_m)^m], m2) in agreement with Fokker–Planck calculations using the measured density profile. Classical heat transport theory is not valid both because the isotropic component of the electron velocity distribution is flattopped and the temperature gradients are very steep. Physics of Plasmas is copyrighted by The American Institute of Physics.

References in the article

Query Results from the Physics/Geophysics Database Retrieved 16 abstracts, starting with number 1. Total number selected: 16.

Liu, J. M., de Groot, J. S., Matte, J. P., Johnston, T. W., & Drake, R. P. 1994, Physical Review Letters Measurements of inverse bremsstrahlung absorption and non-Maxwellian electron velocity distributions

Rogers, J. H., de Groot, J. S., & Hwang, D. Q. 1992, Review of Scientific Instruments Validating cylindrical Langmuir probe techniques

Murnane, Margaret M., Kapteyn, Henry C., Rosen, Mordecai D., & Falcone, Roger W. 1991, Science Ultrafast X-ray pulses from laser-produced plasmas

Minotti, F. & Fontan, C. Ferro 1990, Physics of Fluids B Nonlocal heat transport in plasmas down steep temperature gradients

Rosen, M. D. 1990, Physics of Fluids B Plasma physics issues in laboratory x-ray lasers

Rogers, J. H., de Groot, J. S., Abou-Assaleh, Z., Matte, J. P., Johnston, T. W., & Rosen, M. D. 1989, Physics of Fluids B Electron heat transport in a steep temperature gradient

Alaterre, P., Matte, J.-P., & Lamoureux, M. 1986, Physical Review A Ionization and recombination rates in non-Maxwellian plasmas

Luciani, J. F. & Mora, P. 1986, Physics Letters A Heat flux near critical density in laser-plasma interaction

Kodama, R., Okada, K., Ikeda, N., Mineo, M., & Tanaka, K. A. 1986, Journal of Applied Physics Soft X-ray emission from omega (0), 2 omega (0), and 4 omega (0) laser-produced plasmas

Matte, J. P., Johnston, T. W., Delettrez, J., & McCrory, R. L. 1984, Physical Review Letters Electron Heat Flow with Inverse Bremsstrahlung and Ion Motion

Matthews, D. L., Kauffman, R. L., Kilkenny, J. D., & Lee, R. W. 1984, Applied Physics Letters Electron energy distributions using the time-resolved free-bound spectra from coronal plasmas

Luciani, J. F., Mora, P., & Virmont, J. 1983, Physical Review Letters Nonlocal heat transport due to steep temperature gradients

Albritton, J. R. 1983, Physical Review Letters Laser Absorption and Heat Transport by Non-Maxwell-Boltzmann Electron Distributions

Jones, Roger D. & Lee, K. 1982, Physics of Fluids Kinetic theory, transport, and hydrodynamics of a high-Z plasma in the presence of an intense laser field

Mora, Patrick & Yahi, Hervé 1982, Physical Review A Thermal heat-flux reduction in laser-produced plasmas

Shvarts, D., Delettrez, J., McCrory, R. L., & Verdon, C. P. 1981, Physical Review Letters Self-Consistent Reduction of the Spitzer-Härm Electron Thermal Heat Flux in Steep Temperature Gradients in Laser-Produced Plasmas

Electronic Refereed Journal Article (HTML)

Electron heat transport with non-Maxwellian distributions

Electron heat transport with non-Maxwellian distributions