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Title: Characterization and performance of the upgraded NIRSPEC on the W. M. Keck Telescope
NIRSPEC is a high-resolution near-infrared echelle spectrograph on the Keck II telescope that was commissioned in 1999 and upgraded in 2018. This recent upgrade was aimed at improving the sensitivity and longevity of the instrument through the replacement of the spectrometer science detector (SPEC) and slit-viewing camera (SCAM). Commissioning began in 2018 December, producing the first on-sky images used in the characterization of the upgraded system. Through the use of photometry and spectroscopy of standard stars and internal calibration lamps, we assess the performance of the upgraded SPEC and SCAM detectors. First, we evaluate the gain, readnoise, dark current, and the charge persistence of the spec detector. We then characterize the newly upgraded spectrometer and the resulting improvements in sensitivity, including spectroscopic zero points, pixel scale, and resolving power across the spectrometer detector field. Finally, for SCAM, we present zero points, pixel scale, and provide a map of the geometric distortion of the camera.  more » « less
Award ID(s):
1801978
NSF-PAR ID:
10292792
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ;
Editor(s):
Evans, Christopher J.; Bryant, Julia J.; Motohara, Kentaro
Date Published:
Journal Name:
SPIE Astronomical Telescopes & Instrumentation 2020 Proceedings
Volume:
11447
Page Range / eLocation ID:
121
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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