HR: 0800h
AN: SH31A-1167    [Abstracts]
TI: Hydrodynamics of Shock Waves with Reflected Particles: Rankine-Hugoniot Relations
AU: * Dasgupta, B
EM: dasgupta@ucr.edu
AF: Institute of Geophysics and Planetary Physics, University of California at Riverside, Riverside, CA 92521 United States
AU: Zank, G P
EM: zank@ucr.edu
AF: Institute of Geophysics and Planetary Physics, University of California at Riverside, Riverside, CA 92521 United States
AU: Bedros, R
EM: rbedr001@student.ucr.edu
AF: Institute of Geophysics and Planetary Physics, University of California at Riverside, Riverside, CA 92521 United States
AU: Webb, G M
EM: gmwebb@citrus.ucr.edu
AF: Institute of Geophysics and Planetary Physics, University of California at Riverside, Riverside, CA 92521 United States
AB: The exact mechanism of pickup ion (PUI) acceleration up to anomalous cosmic ray (ACR) energies at the heliospheric termination shock (TS) is a central problem in the physics of outer heliosphere. If we are to properly address shock energization of suprathermal particles, we must answer the question of how suprathermal particles self-consistently interact with a quasi-perpendicular shock and how they modify the structure of the shock. In the outer heliosphere, there is a substantial population of PUIs. Zank et al., (1996), Lee et al., (1996) and Lipatov and Zank (1999) have suggested that PUIs can be reflected preferentially by the cross-shock electrostatic potential. They proposed a new mechanism for the acceleration of PUIs which is often called mutiply reflected ion (MRI) acceleration or shock surfing. In this work we investigate the role of reflected particles in modifying of Rankine-Hugoniot (RH) relations in a simple hydrodynamical framwork. We included the momentum and energy terms introduced by reflected particles into the shock and studied RH conditions on the basis of a geometric formulation of entropy condition. We distinguish those solutions to the RH conditions which correspond to a physically realizable downstream state. It is seen that such shocks have some common features with the combustion shocks. We show that for shocks with reflected particles decelerated solutions of RH condition can exist under some specific conditions as well as subsonic-supersonic transitions. We have considered both perpendicular and highly oblique shocks, finding them to be strongly sheared. Such shear may destabilize the shock.
DE: 7851 Shock waves
DE: 2139 Interplanetary shocks
DE: 2780 Solar wind interactions with unmagnetized bodies
SC: SPA-Solar and Heliospheric Physics [SH]
MN: 2004 AGU Fall Meeting