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arXiv · 1509.03154

MuSCAT: a multicolor simultaneous camera for studying atmospheres of transiting exoplanets

Norio Narita·Akihiko Fukui·Nobuhiko Kusakabe·Masahiro Onitsuka·Tsuguru Ryu·Kenshi Yanagisawa·Hideyuki Izumiura·Motohide Tamura·Tomoyasu Yamamuro
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Abstract

We report a development of a multi-color simultaneous camera for the 188cm telescope at Okayama Astrophysical Observatory in Japan. The instrument, named MuSCAT, has a capability of 3-color simultaneous imaging in optical wavelength where CCDs are sensitive. MuSCAT is equipped with three 1024x1024 pixel CCDs, which can be controlled independently. The three CCDs detect lights in $g'_2$ (400--550 nm), $r'_2$ (550--700 nm), and $z_{s,2}$ (820--920 nm) bands using Astrodon Photometrics Generation 2 Sloan filters. The field of view of MuSCAT is 6.1x6.1 arcmin$^2$ with the pixel scale of 0.358 arcsec per pixel. The principal purpose of MuSCAT is to perform high precision multi-color transit photometry. For the purpose, MuSCAT has a capability of self autoguiding which enables to fix positions of stellar images within ~1 pix. We demonstrate relative photometric precisions of 0.101%, 0.074%, and 0.076% in $g'_2$, $r'_2$, and $z_{s,2}$ bands, respectively, for GJ436 (magnitudes in $g'$=11.81, $r'$=10.08, and $z'$=8.66) with 30 s exposures. The achieved precisions meet our objective, and the instrument is ready for operation.

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Norio Narita, Akihiko Fukui, Nobuhiko Kusakabe, Masahiro Onitsuka, Tsuguru Ryu, Kenshi Yanagisawa, Hideyuki Izumiura, Motohide Tamura, Tomoyasu Yamamuro. 2015-09-10. MuSCAT: a multicolor simultaneous camera for studying atmospheres of transiting exoplanets. https://doi.org/10.1117/1.jatis.1.4.045001

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