  An explanation is proposed for the appearance of slowly drift shadow bursts
in the dynamic spectrum of Jupiter against the background of decameter radio
emission with a quasi-harmonic structure. Background radio emission is caused
by hot ions with a loss cone type distribution function, which generate ion
cyclotron waves due to the effect of double plasma resonance. A flow of hot
ions with a distribution function of the Maxwell type is injected into the
source region, fills the loss cone of generating ions and interrupts the
generation of ion cyclotron waves due to the filling of the loss cone. The
condition under which instability breaks down is obtained, and the optimal
values of the parameters of the injected ions necessary for the occurrence of
bursts in absorption are determined.
