Radio emission spectrum from an interplanetary shock front

The numerical calculations of the dispersion characteristics of the oscillations of hot plasma in a magnetic field indicate that the spectrum of longitudinal waves excited in the solar wind plasma extends significantly in the refractive index region n > 10. This result provides an explanation of the broad emission band and the constant ratio of the frequency bandwidth to the central frequency of radio emission from interplanetary shock fronts. It is shown that the main contribution to radio emission is due to hot electrons escaping from the interplanetary shock front.