Relativistic Effect on Substorm Energetic Particle Injection

• Main Authors: Wei-chen Lin, 林煒程
• Other Authors: Chio-zong Cheng
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/32496014185092187300

碩士 === 國立成功大學 === 物理學系碩博士班 === 97 === In this study, based on a classical electromagnetic pulse model [Zaharia et al., 2000], we proposed a relativistic particle motion model to simulate dispersionless energetic particle injection observed by geosynchronous satellites associated with substorms, and discuss the relativistic effect on particle injection. In our relativistic particle motion model, the particle drift motion and the adiabatic invariant, particle magnetic moment, are different from the classical model [Zaharia et al., 2000]. Our numerical simulation results are in better agreement with the observation data in comparison with the previous results by Zaharia et al. [2000]. In particular, our results show that dispersionless energetic particle injection at geosynchronous orbit is due to the particles swept by the EM pulse from the distance less than 10Re, which is slightly longer than the previous result (<9Re) [Zaharia et al., 2000]. We had also performed numerical simulations to study energetic particle injection at L=3.5 to discuss the effect of different pulse parameters on particle injection. Our modeling results show that when the pulse velocity is reduced and the pulse longitudinal width is increased, more particles can be swept to L=3.5 to account for the observed enhancement of energetic particle fluxed during substorms.