  The current paradigm of cosmic ray (CR) origin states that the most part of
galactic CRs is produced by supernova remnants. The interaction of supernova
ejecta with the interstellar medium after supernova's explosions results in
shocks responsible for CR acceleration via diffusive shock acceleration (DSA).
We use particle-in-cell (PIC) simulations and a combined
PIC-magnetohydrodynamic (PIC-MHD) technique to investigate whether DSA can
occur in oblique high Mach number shocks. Using the PIC method, we follow the
formation of the shock and determine the fraction of the particles that gets
involved in DSA. Then, with this result, we use PIC-MHD simulations to model
the large-scale structure of the plasma and the magnetic field surrounding the
shock and find out whether or not the reflected particles can generate the
upstream turbulence and trigger DSA. We find that the feasibility of this
process in oblique shocks depends strongly on the Alfvenic Mach number, and the
DSA process is more likely triggered at high Mach number shocks.
