Research objectives and content
The main objective of the proposed project is the investigation of the stability propertires of astrophysical shocks. The latters play an important role in numerous astrophysical phenomena such as formations of nonuniformities in various domains in the universe and acceleration of particles to super-high energies. The attention will focus mainly on the stability of supernovae remnants shocks, that are currently widely accepted as sources of energetic particles. The stability investigation is expected to add an important ingredient to the analysis of the relevance and efficiency of the diffusive shock acceleration (or the first order Fermi acceleration) of energetic particles. The experience and insight gained in studying classical gas-dynarnical shocks will be utilized. However, as most astrophysical shocks are either non-stationary or non-planar (or both) the classical Dyakov-Kontorovich criteria for shock instability may not be employed. Therefore, generalized criteria will be formulated that will take into account the time dependence of the shock's intensity as well as its nonplanar geometry. Those criteria will than be employed in order to investigate the stability properties of supernovae remnants shocks and the dependence of those properties on the presence of a population of high energy particles.
Training content (objective, benefit and expected impact)
The proposed project is expected to integrate the insight and experience acquired through the investigations of classical gas-dynamical shocks into the research activities of the group headed by Prof. Drury. In particular, such concepts as corrugation instability and spontaneous emission are expected to improve the understanding of energetic-particles acceleration-mechanisms which is one of the main research topics of the group members. The proposed research will provide the basis for few projects for M.Sc and Ph.D students. Links with industry / industrial relevance (22)