A Relationship Between Transition Region Brightenings, Abundances, and Magnetic Topology

摘要: We present multi-instrument observations of active region (AR) 8048, made between 3 June and 5 June 1997, as part the SOHO Joint Observing Program 33. This AR has a sigmoid-like global shape undergoes transient brightenings in both soft X-rays transition (TR) lines. compute magneto-hydrostatic model magnetic field, using boundary condition photospheric SOHO/MDI. The computed large-scale field lines show that sigmoid is formed by two sets coronal loops. Shorter loops, associated with core SXT emission, coincide loops observed hotter CDS These reveal gradient temperature, from 2 MK at top to 1 MK ends. most closely matching these hot extend along quasi-separatrix layers (QSLs) field. TR SOHO/CDS can also be topology, QSL intersections photosphere, places where separatrices issuing bald patches (sites coming corona are tangent photosphere) intersect photosphere. There are, furthermore, suggestions element abundances measured may depend on type topological structure present. Typically, QSLs have abundances, while those BP closer values. suggest this difference due location manner which reconnection occurs different structures.