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Galeev, A. A.

Publications and source records attributed to Galeev, A. A..

6 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1996

Mars Together 2001: An International Mission of Exploration

The United States and Russia have demonstrated serious interests in Mars and are engaged in long-range exploration programs that include launches from each country in 1996. Both countries have conjectured that a more effective, scientifically rewarding program could be realized if their strengths were combined. The paper will describe some of the aspects of the mission and flight system designs along with plans to implement this major international cooperative endeavor.

Russia↗
NASA NTRS1993

Collisionless parallel shocks

Consideration is given to a collisionless parallel shock based on solitary-type solutions of the modified derivative nonlinear Schroedinger equation (MDNLS) for parallel Alfven waves. The standard derivative nonlinear Schroedinger equation is generalized in order to include the possible anisotropy of the plasma distribution and higher-order Korteweg-de Vies-type dispersion. Stationary solutions of MDNLS are discussed. The anisotropic nature of 'adiabatic' reflections leads to the asymmetric particle distribution in the upstream as well as in the downstream regions of the shock. As a result, nonzero heat flux appears near the front of the shock. It is shown that this causes the stochastic behavior of the nonlinear waves, which can significantly contribute to the shock thermalization.

Khabibrakhmanov, I. KH.↗
NASA NTRS1991

A large-amplitude rotational wave in the Venusian ionosheath

Results are reported of a preliminary analysis of a large-amplitude rotational wave in the Venusian ionosheath. The results are based on an analysis of the Pioneer Venus Orbiter plasma and magnetic field observations from six orbits in the first (1979) tail season. This wave appears to be the standing super-Alfvenic wing. It is located within the shocked plasma flow outside the boundary of the tail. The rotation of the magnetic field by about 90 deg across the wave occurs through several successive cycles making the wave similar to the group velocity wing consisting of phase velocity waves. The transition through the wave is accompanied by the vector change of the plasma velocity with the magnitude of the plasma velocity jump comparable to the vector jump of the Alfven velocity. The observed super-Alfvenic wing appears to originate upstream and closer to the planet, possibly near the upper boundary of the magnetic barrier on the dayside.

Fedorov, A. O.↗
NASA NTRS1985

Solar wind stagnation near comets

The nature of the solar wind flow near comets is examined analytically in this paper. In particular, typical values for the stagnation pressure and magnetic barrier strength are estimated, taking into account magnetic field line tension and change-exchange cooling of the mass-loaded solar wind. A knowledge of the strength of the magnetic barrier is required in order to determine the location of the ionopause surface which separates the contaminated solar wind plasma from the outflowing plasma of the cometary ionosphere.

Galeev, A. A.↗
NASA NTRS1978

Explosive tearing mode reconnection in the magnetospheric tail

A speculative model for the nonlinear phase of the collisionless tearing instability is developed for the case of a single long wavelength tearing mode. Using an energy principle formalism, we find that the nonlinear growth rate is linearly proportional to the mode amplitude. Hence in the nonlinear phase, the tearing mode grows explosively in time, and saturates when the width of the magnetic islands become comparable to the thickness of the current sheet. For typical plasma sheet parameters, the explosive phase lasts 5-10 minutes, and develops cross-tail emf's of several 100 KV.

Galeev, A. A.↗