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Title: Ubiquitous High-frequency Waves and Disturbances in the Active Region Corona Observed with Cryo-NIRSP
The plasma of the solar corona harbors a multitude of coronal wave modes, some of which could be dissipated to provide the required energy and momentum to heat the corona and accelerate the solar wind. We present observations of the corona acquired with the newly commissioned infrared slit spectropolarimeter Cryo-NIRSP at the Daniel K. Inouye Solar Telescope (DKIST), Haleakalā, Hawaii to study the high-frequency wave behavior in closed, active region structures. Cryo-NIRSP observes the corona off the limb in the Fexiii1074 and 1079 nm forbidden atomic lines. The large aperture of DKIST allows us to explore the active region corona with a temporal resolution faster than a second with an achieved spatial resolution of 2″–5″. Enhanced wave power is observed in the coronal power spectra up to 100 mHz. We report evidence for spectroscopic detection of magnetohydrodynamic (MHD) wave modes with periodicities between 30 and 100 s in the observed active region corona and report their changing properties with height. Furthermore, we report on a statistically significant anticorrelation between the Fexiii1074 nm peak line intensity and line width. These observations show how the powerful spectropolarimetric capabilities of DKIST offer great promise for furthering our knowledge of coronal MHD waves.  more » « less
Award ID(s):
2300452 2408437
PAR ID:
10672023
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
IOP Science
Date Published:
Journal Name:
The Astrophysical Journal
Volume:
999
Issue:
1
ISSN:
0004-637X
Page Range / eLocation ID:
34
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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