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SCUBA-2 Ultra Deep Imaging EAO Survey (STUDIES): faint-end counts at 450 μm

Wang, Wei-Hao; Lin, Wei-Ching; Lim, Chen-Fatt; Smail, Ian; Chapman, Scott C.; Zheng, Xian Zhong; Shim, Hyunjin; Kodama, Tadayuki; Almaini, Omar; Ao, Yiping; Blain, Andrew W.; Bourne, Nathan; Bunker, Andrew J.; Chang, Yu-Yen; Chao, Dani C.-Y.; Chen, Chian-Chou; Clements, David L.; Conselice, Christopher J.; Cowley, William I.; Dannerbauer, Helmut; Dunlop, James S.; Geach, James E.; Goto, Tomotsugu; Jiang, Linhua; Ivison, Rob J.; Jeong, Woong-Seob; Kohno, Kotaro; Kong, Xu; Lee, Chien-Hsu; Lee, Hyung Mok; Lee, Minju; Michałowski, Michał J.; Oteo, Iván; Sawicki, Marcin; Scott, Douglas; Shu, Xin Wen; Simpson, James M.; Tee, Wei-Leong; Toba, Yoshiki; Valiante, Elisabetta; Wang, Jun-Xian; Wang, Ran; Wardlow, Julie L.


Wei-Hao Wang

Wei-Ching Lin

Chen-Fatt Lim

Ian Smail

Scott C. Chapman

Xian Zhong Zheng

Hyunjin Shim

Tadayuki Kodama

Omar Almaini

Yiping Ao

Andrew W. Blain

Nathan Bourne

Andrew J. Bunker

Yu-Yen Chang

Dani C.-Y. Chao

Chian-Chou Chen

David L. Clements

Christopher J. Conselice

William I. Cowley

Helmut Dannerbauer

James S. Dunlop

James E. Geach

Tomotsugu Goto

Linhua Jiang

Rob J. Ivison

Woong-Seob Jeong

Kotaro Kohno

Xu Kong

Chien-Hsu Lee

Hyung Mok Lee

Minju Lee

Michał J. Michałowski

Iván Oteo

Marcin Sawicki

Douglas Scott

Xin Wen Shu

James M. Simpson

Wei-Leong Tee

Yoshiki Toba

Elisabetta Valiante

Jun-Xian Wang

Ran Wang

Julie L. Wardlow


The SCUBA-2 Ultra Deep Imaging EAO Survey (STUDIES) is a three-year JCMT Large Program aiming to reach the 450 μm confusion limit in the COSMOS-CANDELS region to study a representative sample of the high-redshift far-infrared galaxy population that gives rise to the bulk of the far-infrared background. We present the first-year data from STUDIES. We reached a 450 μm noise level of 0.91 mJy for point sources at the map center, covered an area of 151 arcmin2, and detected 98 and 141 sources at 4.0σ and 3.5σ, respectively. Our derived counts are best constrained in the 3.5–25 mJy regime using directly detected sources. Below the detection limits, our fluctuation analysis further constrains the slope of the counts down to 1 mJy. The resulting counts at 1–25 mJy are consistent with a power law having a slope of −2.59 (±0.10 for 3.5–25 mJy, and ${}_{-0.7}^{+0.4}$ for 1–3.5 mJy). There is no evidence of a faint-end termination or turnover of the counts in this flux density range. Our counts are also consistent with previous SCUBA-2 blank-field and lensing-cluster surveys. The integrated surface brightness from our counts down to 1 mJy is 90.0 ± 17.2 Jy deg−2, which can account for up to ${83}_{-16}^{+15} \% $ of the COBE 450 μm background. We show that Herschel counts at 350 and 500 μm are significantly higher than our 450 μm counts, likely caused by its large beam and source clustering. High angular resolution instruments like SCUBA-2 at 450 μm are therefore highly beneficial for measuring the luminosity and spatial density of high-redshift dusty galaxies.

Journal Article Type Article
Publication Date Nov 20, 2017
Journal Astrophysical Journal
Print ISSN 0004-637X
Electronic ISSN 1538-4357
Publisher American Astronomical Society
Peer Reviewed Peer Reviewed
Volume 850
Issue 1
APA6 Citation Wang, W., Lin, W., Lim, C., Smail, I., Chapman, S. C., Zheng, X. Z., …Wardlow, J. L. (2017). SCUBA-2 Ultra Deep Imaging EAO Survey (STUDIES): faint-end counts at 450 μm. Astrophysical Journal, 850(1), doi:10.3847/1538-4357/aa911b
Keywords galaxies: high-redshift ; galaxies: evolution ;
submillimeter: galaxies ; cosmology: cosmic ; background radiation
Publisher URL
Copyright Statement Copyright information regarding this work can be found at the following address:


Wang_2017_ApJ_850_37.pdf (1.7 Mb)

Copyright Statement
Copyright information regarding this work can be found at the following address:

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