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arXiv · 1501.03403

A Warm Near-Infrared High-Resolution Spectrograph with Very High Throughput (WINERED)

Sohei Kondo·Yuji Ikeda·Naoto Kobayashi·Chikako Yasui·Hiroyuki Mito·Kei Fukue·Kenshi Nakanishi·Takafumi Kawanishi·Tetsuya Nakaoka·Shogo Otsubo·Masaomi Kinoshita·Ayaka Kitano·Satoshi Hamano·Misaki Mizumoto·Ryo Yamamoto·Natsuko Izumi·Noriyuki Matsunaga·Hideyo Kawakita
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Abstract

WINERED is a newly built high-efficiency (throughput$ > 25-30\%$) and high-resolution spectrograph customized for short NIR bands at 0.9-1.35 ${\rm \mu}$m. WINERED is equipped with ambient temperature optics and a cryogenic camera using a 1.7 ${\rm \mu}$m cut-off HgCdTe HAWAII-2RG array detector. WINERED has two grating modes: one with a conventional reflective echelle grating (R$\sim$28,300), which covers 0.9-1.35 $\mu$m simultaneously, the other with ZnSe or ZnS immersion grating (R$\sim$100,000). We have completed the development of WINERED except for the immersion grating, and started engineering and science observations at the Nasmyth platform of the 1.3 m Araki Telescope at Koyama Astronomical Observatory of Kyoto-Sangyo University in Japan. We confirmed that the spectral resolution ($R\sim$ 28,300) and the throughput ($>$ 40\% w/o telescope/atmosphere/array QE) meet our specifications. We measured ambient thermal backgrounds (e.g., 0.06 ${\rm [e^{-}/sec/pixel]}$ at 287 K), which are roughly consistent with that we expected. WINERED is a portable instrument that can be installed at any telescope with Nasmyth focus as a PI-type instrument. If WINERED is installed on a 10 meter telescope, the limiting magnitude is expected to be J=18-19, which can provide high-resolution spectra with high quality even for faint distant objects.

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Sohei Kondo, Yuji Ikeda, Naoto Kobayashi, Chikako Yasui, Hiroyuki Mito, Kei Fukue, Kenshi Nakanishi, Takafumi Kawanishi, Tetsuya Nakaoka, Shogo Otsubo, Masaomi Kinoshita, Ayaka Kitano, Satoshi Hamano, Misaki Mizumoto, Ryo Yamamoto, Natsuko Izumi, Noriyuki Matsunaga, Hideyo Kawakita. 2015-01-14. A Warm Near-Infrared High-Resolution Spectrograph with Very High Throughput (WINERED). https://arxiv.org/abs/1501.03403

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