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  • High-resolution He I 10 830 Å narrowband imaging for precursors of chromospheric jets and their quasi-periodic properties
Title: High-resolution He I 10 830 Å narrowband imaging for precursors of chromospheric jets and their quasi-periodic properties
Solar jets are well-collimated plasma ejections in the solar atmosphere. They are prevalent in active regions, the quiet Sun, and even coronal holes. They display a range of temperatures, yet the nature of the cool components has not been fully investigated. In this paper, we show the existence of the precursors and quasi-periodic properties for two chromospheric jets, mainly utilizing the He  I 10 830 Å narrowband filtergrams taken by the Goode Solar Telescope (GST). The extreme ultraviolet (EUV) counterparts present during the eruption correspond to a blowout jet (jet 1) and a standard jet (jet 2), as observed by the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamic Observatory (SDO). The high-resolution He  I 10 830 Å observation captures a long-lasting precursor for jet 1, signified by a series of cool ejections. They are recurrent jet-like features with a quasi-period of about five minutes. On the other hand, the cool components of jet 2, recurrently accompanied by EUV emissions, present a quasi-periodic behavior with a period of about five minutes. Both the EUV brightening and He  I 10 830 Å absorption show that there was a precursor for jet 2 that occurred about five minutes before its onset. We propose that the precursor of jet 1 may be the consequence of chromospheric shock waves, since the five-minute oscillation from the photosphere can leak into the chromosphere and develop into shocks. Then, we find that the quasi-periodic behavior of the cool components of jet 2 may be related to magnetic reconnections modulated by the oscillation in the photosphere.  more » « less
Award ID(s):
1821294 2309939 2108235
PAR ID:
10408498
Author(s) / Creator(s):
; ; ; ; ;
Date Published:
Journal Name:
Astronomy & Astrophysics
Volume:
672
ISSN:
0004-6361
Page Range / eLocation ID:
A173
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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