时间：2010年9月21日（星期二）上午10:00－11:30

地点：空间科学与物理学院学术报告厅

题目：Heliospheric current sheet and plasma sheet associated with heat flux dropouts: A statistical survey using STEREO observations.

主讲：刘勇博士

刘勇博士简介：

1994年毕业于武汉大学无线电物理专业。

2006年UNH获得博士学位，空间物理方向，导师MARTIN LEE。

2007年从事CME模拟研究，博士后导师是MERAV OPHER。

2008年回到UNH，从事粒子探测仪器的数据定标工作。

报告内容简介：

Early studies have shown that the heliospheric plasma sheet (HPS) straddles heliospheric current sheet (HCS); recent study find that most of HPSs are on one side of and adjacent to HCSs. We investigate all HCS crossing events and the related HPS on both STEREO spacecraft from Mar, 1, 2007 to Dec, 2008 to determine the relative position for them. We find that the observed plasma sheets can be categorized into two types: Type I plasma sheets straddle the current sheets; type II plasma sheets are located on the one side of the current sheets. The suprathermal electron heat fluxes are documented for each event to study the origin of the different type of HPS. We find that most of the Type II HCSs don’t have an electron heat flux dropout (HFD), but a large portion of type I HPSs have a HFD near it. Schematic reconnection mechanisms are proposed to explain the origin of the two types of HPSs.