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Title: Coronagraphic Observations of Si x 1430 nm Acquired by DKIST/Cryo-NIRSP with Methods for Telluric Absorption Correction
Abstract

We report commissioning observations of the Six1430 nm solar coronal line observed coronagraphically with the Cryogenic Near-Infrared Spectropolarimeter at the National Science Foundation’s Daniel K. Inouye Solar Telescope. These are the first known spatially resolved observations of this spectral line, which has strong potential as a coronal magnetic field diagnostic. The observations target a complex active region located on the solar northeast limb on 2022 March 4. We present a first analysis of these data that extracts the spectral line properties through a careful treatment of the variable atmospheric transmission that is known to impact this spectral window. Rastered images are created and compared with extreme-UV observations from the Solar Dynamics Observatory (SDO) Atmospheric Imaging Assembly (AIA) instrument. A method for estimating the electron density from the Sixobservations is then demonstrated that makes use of the forbidden line density-sensitive emissivity and an emission-measure analysis of the SDO/AIA bandpass observations. In addition, we derive an effective temperature and nonthermal line width across the region. This study informs the calibration approaches required for more routine observations of this promising diagnostic line.

 
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NSF-PAR ID:
10498782
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Publisher / Repository:
DOI PREFIX: 10.3847
Date Published:
Journal Name:
The Astrophysical Journal
Volume:
965
Issue:
1
ISSN:
0004-637X
Format(s):
Medium: X Size: Article No. 40
Size(s):
["Article No. 40"]
Sponsoring Org:
National Science Foundation
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