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arXiv · 2111.00751

Method for tilt correction of calibration lines in high resolution spectra

Tanya Das·Ravinder K. Banyal
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Abstract

Technological advancement has led to improvement in the design capabilities of astronomical spectrographs, allowing for high precision spectroscopy, thereby expanding the realms of observational astronomy. High-resolution spectrographs use Echelle grating that operates in higher orders, giving more detailed spectra. Often, curvature and tilted lines are observed in the spectra, arising due to the design trade-offs of the respective spectrographs. Removal of these artifacts can help avoid wrong flux calculation and line centroid position misinterpretation, which can aid in a better prediction of the wavelength calibration model. In this paper we present a post-processing technique that we developed to correct the observed curvature and tilt in the spectra. We have demonstrated the correction technique on Fabry-Perot and Th-Ar calibration spectra obtained from Hanle Echelle Spectrograph (HESP), Magellan Inamori Kyocera Echelle (MIKE) spectrometer and X-shooter spectrograph.

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Tanya Das, Ravinder K. Banyal. 2021-11-01. Method for tilt correction of calibration lines in high resolution spectra. https://doi.org/10.1364/ao.434198

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