*Tomoko Nakagawa1, Hideo Tsunakawa2, Yoshifumi Saito3, Masaki N Nishino4
(1.Information and Communication Engineering, Tohoku Institute of Technology, 2.Deparment of Earth and Planetary Sciences, Tokyo Institute of Technology, 3.Solar System Science Division, ISAS, JAXA, 4.Institute for Space-Earth Environmental Research, Nagoya University)
Keywords:electron beam, magnetic field variation, lunar wake, type II entry protons, whistler mode wave, oblique propagation
Generation mechanism of the magnetic fluctuations in the ELF range detected by MAP-LMAG magnetometer onboard Kaguya in the deepest wake behind the moon associated with the type-II entry protons is studied. Most of the waves were detected on the magnetic field lines which were not connected with the lunar surface, along which the solar wind electrons were injected into the wake. The waves had compressional components of field variation, suggesting that the direction of the wave number vector was oblique with respect to the background magnetic field. Interaction between the field-aligned hot electron beam and oblique whistler and electrostatic waves is considered.