SM13C-2512
Ion Dynamics and Field Structure of Quasi-perpendicular Collisionless Shocks near the Critical Mach Number

Monday, 14 December 2015
Poster Hall (Moscone South)
Ma Malkov1, Roald Sagdeev2, Galina Dudnikova2 and Michael A Balikhin3, (1)University of California San Diego, La Jolla, CA, United States, (2)University of Maryland College Park, Physics, College Park, MD, United States, (3)University of Sheffield, Sheffield, S10, United Kingdom
Abstract:
The structure of subcritical (laminar) collisionless shocks has been understood long time ago. When the Mach number exceeds a critical value, some of the incident ions are reflected. This needs to be included into the description of the shock structure and entropy production at the shock front. We present an analytical model of ion reflection from a quasi-perpendicular collisionless shock and the formation of the foot region associated with this reflection. Reflected ions perturb the electrostatic and magnetic fields in the foot region which we self-consistently include in determining the fraction of reflected ions, depending on the Mach number of the shock. The subsequent motion of the shock reflected ions downstream and formation of the downstream field structure is analyzed. Models for thermalization of the downstream plasma and approaches to Rankine-Hugoniot relations will also be discussed. The obtained overall shock structure is compared with the Cluster observations.