Marybeth Sechler, Scott W. McIntosh, Hui Tian, Bart De Pontieu
Using joint observations from Hinode/EIS and the Atmospheric Imaging Array
(AIA) on the Solar Dynamics Observatory we explore the asymmetry of coronal EUV
line profiles. We find that asymmetries exist in all of the spectral lines
studied, and not just the hottest lines as has been recently reported in the
literature. Those asymmetries indicate that the velocities of the second
emission component are relatively consistent across temperature and consistent
with the apparent speed at which material is being inserted from the lower
atmosphere that is visible in the SDO/AIA images as propagating coronal
disturbances. Further, the observed asymmetries are of similar magnitude (a few
%) and width (determined from the RB analysis) across the temperature space
sampled and in the small region studied. Clearly, there are two components of
emission in the locations where the asymmetries are identified in the RB
analysis, their characteristics are consistent with those determined from the
SDO/AIA data. There is no evidence from our analysis that this second component
is broader than the main component of the line.
View original:
http://arxiv.org/abs/1201.5028
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