9月27日Tony Lui教授作学术报告

2011年9月27日下午2:00 Geroge Parks学术报告。

报告题目:Energy source for auroral electrons from two proposed substorm onset process

摘要:There are two main processes in the tail that are proposed to link electron precipitation for the auroral arc during substorms. These are current disruption/dipolarization (CDD) and magnetic reconnection (MR). To provide further clues in differentiating these two processes, we examine the electron energy spectrum and the associated total field-aligned energy flux during six CDD events and compare them with five MR events. It is found that (1) the total field-aligned electron energy flux from CDD sites is generally high enough to account for the energy flux required to produce bright auroral arcs and (2) the total field-aligned electron energy flux from MR sites is generally a factor of one to two orders of magnitude lower than that from CDD sites. These results favor a direct link between the CDD sites and the substorm arcs. Further acceleration by other mechanisms is considered with the result that inclusion of other mechanisms is unlikely to alter the differences obtained in this analysis.