Compound Solar Eruptions: the phenomena, processes and possible causes----中国科学院紫金山天文台

Seminar Title	Compound Solar Eruptions: the phenomena, processes and possible causes

Speaker:	Prof. Jie Zhang

Affiliation:	(Department of Physics and Astronomy, George Mason University, USA)

When	Wednesday morning, July 5, 10:00-11:00 a.m

Where:	Room 416, Office Block, 2 West Beijing Road (PMO, CAS)
	Welcome to Attend

	( PMO Academic Committee & Academic Circulating committee)

Abstract: Standard and popular models of solar eruptions, including solar flares and coronal mass ejections (CMEs) have been focusing on singular solar eruption, i.e., a single peak of main phase and an eruption of a single magnetic structure. In this talk, I will discuss non-singular eruptions that involve multiple magnetic flux structure arranged closely in space and erupting consecutively in a short time. In particular, we analyze and report a compound eruption process associated with an M8.4 flare occurred on March 10, 2012 in NOAA AR 11429. In the main phase of the flare, there were two major peaks in GOES X-ray at ~17:20 UT and ~ 17:40 UT respectively. We found that the two flare peaks, separated by about 20 minutes, corresponded to two individual erupting magnetic flux bundles from the same active region and along the same magnetic polarity inversion line. The erupting features were seen as a hot channel-like structure of a temperature of ~ 10 MK in coronal images obtained from SDO AIA 131 A passband. We believe that each erupting feature is originated from an individual magnetic flux bundle. Prior to the onset of the eruption, the magnetic structure of the source region likely contains a double decker configuration, i.e., a coherent flux bundle lies above another coherent flux bundle. This study demonstrates that complex magnetic configuration could form in the corona and result in a compound solar eruption that involves energy release in different magnetic structures. We will discuss the physical processes that could inter-connect multiple magnetic structures in active regions and across the Sun.