Propagation modes and source locations of the auroral kilometric radiation (AKR) identified by using the wave distribution function method

摘要

The propagation characteristics of Auroral Kilometric Radiation (AKR), the propagation mode, power flux as well as propagation direction, have been analyzed by applying the wave distribution function method to the Poynting Flux measurement data obtained by the PWS system onboard the Akebono (EXOS-D) satellite. The results revealed that the power flux of O-mode waves was about 10 percent of the X-mode wave intensity in strong AKR emissions. The X-mode AKR waves tend to fill inside the radiation cone of an auroral field line. On the other hand, O-mode AKR showed two different propagation directions, one was directed to almost 90° with respect to the local magnetic field and the other showed angle in the vicinity of 40°. It was shown that the source locations of O-mode AKR waves with the propagation angle of about 40° located close to the source of the intense X-mode AKR waves.