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arXiv · 1808.04502

Alma Twenty-six Arcmin^2 Survey Of Goods-s At One-millimeter (asagao): Source Catalog And Number Counts

Abstract

We present the survey design, data reduction, construction of images, and source catalog of the Atacama Large Millimeter/submillimeter Array (ALMA) twenty-six arcmin^2 survey of GOODS-S at one-millimeter (ASAGAO). ASAGAO is a deep (1sigma ~ 61 uJy/beam for a 250 klambda-tapered map with a synthesized beam size of 0.51" x 0.45") and wide area (26 arcmin^2) survey on a contiguous field at 1.2 mm. By combining with ALMA archival data in the GOODS-South field, we obtained a deeper map in the same region (1sigma ~ 30 uJy/beam for a deep region with a 250 klambda-taper, and a synthesized beam size of 0.59" x 0.53"), providing the largest sample of sources (25 sources at >=5.0sigma, 45 sources at >=4.5sigma) among ALMA blank-field surveys to date. The number counts shows that 52(+11 -8)% of the extragalactic background light at 1.2 mm is resolved into discrete sources at S1.2m > 135 uJy. We create infrared (IR) luminosity functions (LFs) in the redshift range of z = 1-3 from the ASAGAO sources with KS-band counterparts, and constrain the faintest luminosity of the LF at 2.0 < z < 3.0. The LFs are consistent with previous results based on other ALMA and SCUBA-2 observations, which suggest a positive luminosity evolution and negative density evolution with increasing redshift. We find that obscured star-formation of sources with IR luminosities of log(L(IR)/Lsun)} ~> 11.8 account for ~~60%-90% of the z ~ 2 cosmic star-formation rate density.

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Bunyo Hatsukade, Kotaro Kohno, Yuki Yamaguchi, Hideki Umehata, Yiping Ao, Itziar Aretxaga, Karina I. Caputi, James S. Dunlop, Eicihi Egami, Daniel Espada, Seiji Fujimoto, Natsuki Hayatsu, David H. Hughes, Soh Ikarashi, Daisuke Iono, Rob J. Ivison, Ryohei Kawabe, Tadayuki Kodama, Minju Lee, Yuichi Matsuda, Kouihiro Nakanishi, Kouji Ohta, Masami Ouchi, Wiphu Rujopakarn, Tomoko Suzuki, Yocihi Tamura, Yoshihiro Ueda, Tao Wang, Wei-hao Wang, Grant W. Wilson, Yuki Yoshimura, Min S. Yun. 2018-08-14. Alma Twenty-six Arcmin^2 Survey Of Goods-s At One-millimeter (asagao): Source Catalog And Number Counts. https://doi.org/10.1093/pasj%2Fpsy104

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