Excitation of chorus-type quasi-periodic VLF signals by whistlers

The paper examines Intercosmos-19 data obtained on May 26, 1981 on chorus signals excited by whistlers. The generation of these signals is explained by the capture of part of the energy of a whistler by an LHR waveguide of the upper atmosphere and by the propagation of captured waves in the waveguide. This explains the main features of the signals, i.e., the frequency range near 3 kHz and the characteristic times between individual quasi-chorus elements of 0.1-0.2 sec.