Observations of the earth's bow shock under high Mach number/high plasma beta solar wind conditions

Using 221 observations of the earth's bow shock by ISEE-1, the magnetic field characteristics of the shock are investigated as a function of Mach number and plasma beta. It is found that immediately behind the overshoot of the shock large amplitude waves develop preferentially with increasing Alfven Mach number and/or plasma beta. Their probability of occurrence is very high in the parallel regime, and declines to near zero probability when theta(BN) reaches 75 deg. It is estimated that approximately 10 percent of the total solar wind energy density is dissipated by these waves.