Correction of Near-infrared High-resolution Spectra for Telluric Absorption at 0.90–1.35 μm. (21st May 2018)

• Record Type: Journal Article
• Authors: Sameshima, Hiroaki; Matsunaga, Noriyuki; Kobayashi, Naoto; Kawakita, Hideyo; Hamano, Satoshi; Ikeda, Yuji; Kondo, Sohei; Fukue, Kei; Taniguchi, Daisuke; Mizumoto, Misaki; Arai, Akira; Otsubo, Shogo; Takenaka, Keiichi; Watase, Ayaka; Asano, Akira; Yasui, Chikako; Izumi, Natsuko; Yoshikawa, Tomohiro
• Is Part Of: Publications of the Astronomical Society of the Pacific. Volume 130:Number 989(2018)
• Publication Date: 2018-05-21
• Subjects: atmospheric effects -- instrumentation: spectrographs -- methods: data analysis -- methods: observational -- techniques: spectroscopic; Astronomy -- Periodicals; Astronomy; Periodicals; Periodicals; 520.5
• DOI: 10.1088/1538-3873/aac1b4
• Languages: English
• ISSNs: 0004-6280

Abstract

Abstract: We report a method of correcting a near-infrared (0.90–1.35 μ m) high-resolution ( λ /Δ λ ∼ 28, 000) spectrum for telluric absorption using the corresponding spectrum of a telluric standard star. The proposed method uses an A0 V star or its analog as a standard star from which on the order of 100 intrinsic stellar lines are carefully removed with the help of a reference synthetic telluric spectrum. We find that this method can also be applied to feature-rich objects having spectra with heavily blended intrinsic stellar and telluric lines and present an application to a G-type giant using this approach. We also develop a new diagnostic method for evaluating the accuracy of telluric correction and use it to demonstrate that our method achieves an accuracy better than 2% for spectral parts for which the atmospheric transmittance is as low as ∼20% if telluric standard stars are observed under the following conditions: (1) the difference in airmass between the target and the standard is ≲ 0.05 ; and (2) that in time is less than 1 hr. In particular, the time variability of water vapor has a large impact on the accuracy of telluric correction and minimizing the difference in time from that of the telluric standard star is important especially in near-infrared high-resolution spectroscopic observation.