Spectroscopic Inversions & Calibrations for DKIST Coronal Observations

Abstract:

The Cryo-NIRSP’s (Cryogenic Near-IR Spectro-Polarimeter) is one of the DKIST instruments capable of sensitive imaging of faint infrared coronal solar spectra, and its primary goal is to measure the full polarization state (Stokes I, Q, U and V) of spectral lines originating on the Sun at different wavelengths. Producing data products from off-limb solar coronal observations from the DKIST telescope is essential when trying to study its future observations. Quantifying the accuracy of spectral inversion procedures based on its spectral comparisons to absorption and telluric calibrated spectra will give insight to interpreting valid DKIST observations and its ultimate findings. Using simulated contaminated data of both pure and noisy data sets has allowed us to compare the wavelength shifts and broadening properties to help pinpoint where contamination would affect the data set as a whole, and by how much. In doing so, we developed code that will eventually be integrated in the DKIST Level-2 pipeline. Working to compare these findings to absorption and telluric readings will further help minimize the uncertainties read in through observations, and give direction on how to reduce the original coronal data in hopes to refine it. Understanding the origins and magnitude of the contamination would therefore help refine the original coronal data and make it compatible for data processing, and would assist the automation of processing the data observed by the DKIST telescope.