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arXiv · 1602.04820

Quiet Sun Hα Transients and Corresponding Small-Scale Transition Region and Coronal Heating

V. M. J. Henriques·D. Kuridze·M. Mathioudakis·F. P. Keenan
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Abstract

Rapid Blue- and Red-shifted Excursions (RBEs and RREs) are likely to be the on-disk counterparts of Type II spicules. Recently, heating signatures from RBEs/RREs have been detected in IRIS slit-jaw images dominated by transition-region lines around network patches. Additionally, signatures of Type II spicules have been observed in AIA diagnostics. The full-disk, ever-present nature of the AIA diagnostics should provide us with sufficient statistics to directly determine how important RBEs and RREs are to the heating of the transition region and corona. We find, with high statistical significance, that at least 11% of the low-coronal brightenings detected in a quiet-Sun region in 304, can be attributed to either RBEs or RREs as observed in Hα, and a 6% match of 171 detected events to RBEs or RREs with very similar statistics for both types of Hα features. We took a statistical approach that allows for noisy detections in the coronal channels and provides us with a lower, but statistical significant, bound. Further, we consider matches based on overlapping features in both time and space, and find strong visual indications of further correspondence between coronal events and co-evolving but non-overlapping, RBEs and RREs.

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V. M. J. Henriques, D. Kuridze, M. Mathioudakis, F. P. Keenan. 2016-02-15. Quiet Sun Hα Transients and Corresponding Small-Scale Transition Region and Coronal Heating. https://doi.org/10.3847/0004-637x%2F820%2F2%2F124

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