SCUBA-2 Ultra Deep Imaging EAO Survey (STUDIES): Faint-End Counts at 450 um
| Autor: | 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, Michalowski, Michal J., Oteo, Ivan, 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. |
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| Rok vydání: | 2017 |
| Předmět: | |
| Druh dokumentu: | Working Paper |
| DOI: | 10.3847/1538-4357/aa911b |
| Popis: | The SCUBA-2 Ultra Deep Imaging EAO Survey (STUDIES) is a three-year JCMT Large Program aiming at reaching the 450 $\mu$m 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 have reached a 450 $\mu$m noise level of 0.91~mJy for point sources at the map center, covered an area of 151 arcmin$^2$, and detected 98 and 141 sources at 4.0 and 3.5 $\sigma$, 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 $-2.59$ ($\pm0.10$ for 3.5-25 mJy, and $^{+0.4}_{-0.7}$ for 1-3.5 mJy). There is no evidence of a faint-end termination or turn-over 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 $90.0\pm17.2$ Jy deg$^{-2}$, which can account for up to $83^{+15}_{-16}\%$ of the COBE 450 $\mu$m background. We show that Herschel counts at 350 and 500 $\mu$m are significantly higher than our 450 $\mu$m counts, likely caused by its large beam and source clustering. High-angular resolution instruments like SCUBA-2 at 450 $\mu$m are therefore highly beneficial for measuring the luminosity and spatial density of high-redshift dusty galaxies. Comment: ApJ accepted. revised version uploaded |
| Databáze: | arXiv |
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