题目：Classification of current sheets in the solar wind and their effects on the transport of SEPs

主讲：李刚 教授

时间：2011年8月19日(星期五)下午2:30 -

地点：学术报告厅

报告简介：Current sheets is a common structure in the solar wind. It is a significant source of solar wind MHD turbulence intermittency. The origin of these structure is presently unknown. Non-linear interactions of the solar wind MHD turbulence can spontaneously generate these structures. On the other hand, there are proposals that these structures may represent relic structures having solar origins. Using a technique developed in [Li 2008], we have examined current sheets in the solar wind from Ulysses observations [Miao et al., 2011]. We found that these structures occur frequently in the solar wind and therefore can affect the propagation of solar energetic particles [Qin & Li, 2008]. Very recently, we have also found there are two classes of current sheets, being "gradual" and "abrupt", where "gradual" ("abrupt") current sheet has the magnetic field changing its direction gradually (abruptly) from one side of the current sheet to the other. Amont "abrupt" current sheets, there are further "single-peak" event and "double-peak" events. We discuss the implication of having "double-peak" events of the origin of the current sheets.

报告人简介：

李刚，美国阿拉巴马大学空间等离子体研究中心Research Scientist (PI)，兼物理系助理教授(Assistant Professor, 08年至今)。94年毕业于清华大学物理系，获学士学位；00年毕业于印地安纳大学物理系，获天体物理学博士及计算机硕士学位；02-08年分别任加州大学河边分校博士后、地球物理与行星物理研究所（IGPP）Assistant Research Scientist、加州大学伯克利分校空间科学实验室(SSL) Assistant Research Physicist。曾获美国自然科学基金委（NSF）的2009年度早期成就奖(NSF Early Career Award),以及国际纯粹及应用物理联合会（IUPAP）的年轻科学家奖。