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A test of the Hall-MHD model: Application to low-frequency upstream waves at VenusEarly studies suggested that in the range of parameter space where the wave angular frequency is less than the proton gyrofrequency and the plasma beta, the ratio of the thermal to magnetic pressure, is less than 1 magnetohydrodynamics provides an adequate description of the propagating modes in a plasma. However, recently, Lacombe et al. (1992) have reported significant differences between basic wave characteristics of the specific propagation modes derived from linear Vlasov and Hall-magnetohydrodynamic (MHD) theories even when the waves are only weakly damped. In this paper we compare the magnetic polarization and normalization magnetic compression ratio of ultra low frequency (ULF) upstream waves at Venus with magnetic polarization and normalized magnetic compression ratio derived from both theories. We find that while the 'kinetic' approach gives magnetic polarization and normalized magnetic compression ratio consistent with the data in the analyzed range of beta (0.5 less than beta less than 5) for the fast magnetosonic mode, the same wave characteristics derived from the Hall-MHD model strongly depend on beta and are consistent with the data only at low beta for the fast mode and at high beta for the intermediate mode.
Document ID
19950038018
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Orlowski, D. S. (University of California, Los Angeles, CA United States)
Russell, C. T. (University of California, Los Angeles, CA United States)
Krauss-Varban, D. (University of California, San Diego, CA United States)
Omidi, N. (University of California, San Diego, CA United States)
Date Acquired
August 16, 2013
Publication Date
January 1, 1994
Publication Information
Publication: Journal of Geophysical Research
Volume: 99
Issue: A1
ISSN: 0148-0227
Subject Category
LUNAR AND PLANETARY EXPLORATION
Funding Number(s)
CONTRACT_GRANT: NAGW-2886
CONTRACT_GRANT: NAGW-2139
CONTRACT_GRANT: NAG2-501
Distribution Limits
Public
Copyright
Other