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arXiv · 2402.18077

Locating heating channels of the solar corona in a plage region with the aid of high-resolution 10830 \AA\ filtergrams

Parida Hashim·Fangyu Xu·Ya Wang·Weijie Men·Jinhua Shen·Yingna Su·Jianping Li·Zhenyu Jin·Haisheng Ji
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Abstract

In this paper, with a set of high-resolution He I 10830 \AA\ filtergrams, we select an area in a plage, very likely an EUV moss area, as an interface layer to follow the clues of coronal heating channels down to the photosphere. The filtergrams are obtained from the 1-meter aperture New Vacuum Solar Telescope (NVST). We make a distinction between the darker and the brighter regions in the selected area and name the two regions enhanced absorption patches (EAPs) and low absorption patches (LAPs). With well-aligned, nearly simultaneous data from multiple channels of the AIA and the continuum of the HMI on board SDO, we compare the EUV/UV emissions, emission measure, mean temperature, and continuum intensity in the two kinds of regions. The following progress is made: 1) The mean EUV emissions over EAPs are mostly stronger than the corresponding emissions over LAPs except for the emission at 335 \AA. The UV emissions at 1600 and 1700 \AA\ fail to capture the difference between the two regions. 2) In the logarithmic temperature range of 5.6-6.2, EAPs have higher EUV emission measure than LAPs, but they have lower mean coronal temperature. 3) The mean continuum intensity over EAPs is lower. Based on the above progress, we suggest that the energy for coronal heating in the moss region can be traced down to some areas in intergranular lanes with enhanced density of both cool and hot material. The lower temperature over the EAPs is due to the greater fraction of cool material over there.

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Parida Hashim, Fangyu Xu, Ya Wang, Weijie Men, Jinhua Shen, Yingna Su, Jianping Li, Zhenyu Jin, Haisheng Ji. 2024-02-28. Locating heating channels of the solar corona in a plage region with the aid of high-resolution 10830 \AA\ filtergrams. https://arxiv.org/abs/2402.18077

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