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arXiv · 2005.04253

Rapid Evolution of Type II Spicules Observed in Goode Solar Telescope On-Disk H-alpha Images

Vasyl Yurchyshyn·Wenda Cao·Valentina Abramenko·Xu Yang·Kyung-Suk Cho
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Abstract

We analyze ground-based chromospheric data acquired at a high temporal cadence of 2 s in wings of the H$\alpha$ spectral line using Goode Solar Telescope (GST) operating at the Big Bear Solar Observatory. We inspected a 30 minute long H$\alpha$-0.08~nm data set to find that rapid blue-shifted H$\alpha$ excursions (RBEs), which are a cool component of type II spicules, experience very rapid morphological changes on the time scales of the order of 1 second. Unlike typical reconnection jets, RBEs very frequently appear \textit{in situ} without any clear evidence of H$\alpha$ material being injected from below. Their evolution includes inverted "Y", "V", "N", and parallel splitting (doubling) patterns as well as sudden formation of a diffuse region followed by branching. We also find that the same feature may undergo several splitting episodes within about 1 min time interval.

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Vasyl Yurchyshyn, Wenda Cao, Valentina Abramenko, Xu Yang, Kyung-Suk Cho. 2020-05-08. Rapid Evolution of Type II Spicules Observed in Goode Solar Telescope On-Disk H-alpha Images. https://doi.org/10.3847/2041-8213/ab7931

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