  The characteristics of the gravitational collapse of a supernova and the
fluxes of active and sterile neutrinos produced during the formation of its
protoneutron core have been calculated numerically. The relative yields of
active and sterile neutrinos in core matter with different degrees of
neutronization have been calculated for various input parameters and various
initial conditions. A significant increase in the fraction of sterile neutrinos
produced in superdense core matter at the resonant degree of neutronization has
been confirmed. The contributions of sterile neutrinos to the collapse dynamics
and the total flux of neutrinos produced during collapse have been shown to be
relatively small. The total luminosity of sterile neutrinos is considerably
lower than the luminosity of electron neutrinos, but their spectrum is
considerably harder at high energies.
