Pitch angle measurement method based on detector counts distribution. -I. basic conception
摘要
As an X-ray and gamma-ray all-sky monitor designed to observe high-energy astrophysical transients, Gravitational-wave high-energy Electromagnetic Counterpart All-sky Monitor (GECAM) has also made a series of observational on burst events of gamma-rays and particles in the low Earth orbit. Pitch angle is one of the key parameters of charged particles traveling around the geomagnetic field. However, the usage of the all-sky monitor (GECAM-style) instruments to measure the pitch angle of charged particles is still lacking. In this work, we propose a novel method for GECAM and similar instruments to measure the pitch angle of charged particles based on detector counts distribution. The basic concept of this method, along with supporting simulation studies, is presented. With this method, the pitch angle of a peculiar electron precipitation event detected by GECAM-C is derived to be about 90