Abstract
We have observed ~30 Hz EMIC wave on September 8, 2017
at ~10:45 to 10:55 UT. This wave is a 2XH+ EMIC wave.
This wave was generated by pitch angle anisotropy of protons with
energies in the range of ~40eV - 450eV. This anisotropy
is likely resulted from strong background Magnetosonic wave. The high
frequency EMIC wave caused precipitation of low energy particles in the
ionosphere.