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MOIRCS Deep Survey. I: DRG Number Counts

Masaru Kajisawa·Masahiro Konishi·Ryuji Suzuki·Chihiro Tokoku·Yuka Katsuno Uchimoto·Tomohiro Yoshikawa·Masayuki Akiyama·Takashi Ichikawa·Masami Ouchi·Koji Omata·Ichi Tanaka·Tetsuo Nishimura·Toru Yamada
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Abstract

We use very deep near-infrared imaging data taken with Multi-Object InfraRed Camera and Spectrograph (MOIRCS) on the Subaru Telescope to investigate the number counts of Distant Red Galaxies (DRGs). We have observed a 4x7 arcmin^2 field in the Great Observatories Origins Deep Survey North (GOODS-N), and our data reach J=24.6 and K=23.2 (5sigma, Vega magnitude). The surface density of DRGs selected by J-K>2.3 is 2.35+-0.31 arcmin^-2 at K<22 and 3.54+-0.38 arcmin^-2 at K<23, respectively. These values are consistent with those in the GOODS-South and FIRES. Our deep and wide data suggest that the number counts of DRGs turn over at K~22, and the surface density of the faint DRGs with K>22 is smaller than that expected from the number counts at the brighter magnitude. The result indicates that while there are many bright galaxies at 2 22 suggest that the mass-dependent color distribution, where most of low-mass galaxies are blue while more massive galaxies tend to have redder colors, had already been established at that epoch.

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Masaru Kajisawa, Masahiro Konishi, Ryuji Suzuki, Chihiro Tokoku, Yuka Katsuno Uchimoto, Tomohiro Yoshikawa, Masayuki Akiyama, Takashi Ichikawa, Masami Ouchi, Koji Omata, Ichi Tanaka, Tetsuo Nishimura, Toru Yamada. 2006-10-12. MOIRCS Deep Survey. I: DRG Number Counts. https://doi.org/10.1093/pasj%2F58.6.951

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