학술논문
The SCUBA-2 Large eXtragalactic Survey: 850um map, catalogue and the bright-end number counts of the XMM-LSS field
Document Type
Working Paper
Author
Garratt, T. K.; Geach, J. E.; Tamura, Y.; Coppin, K. E. K.; Franco, M.; Ao, Y.; Chen, C. -C.; Cheng, C.; Clements, D. L.; Dai, Y. S.; Dannerbauer, H.; Greve, T. R.; Hatsukade, B.; Hwang, H. S.; Jiang, L.; Kohno, K.; Koprowski, M. P.; Michalowski, M. J.; Sawicki, M.; Scott, D.; Shim, H.; Takeuchi, T. T.; Wang, W. -H.; Xue, Y. Q.; Yang, C.
Source
Subject
Language
Abstract
We present 850um imaging of the XMM-LSS field observed for 170 hours as part of the James Clerk Maxwell Telescope SCUBA-2 Large eXtragalactic Survey (S2LXS). S2LXS XMM-LSS maps an area of 9 square degrees, reaching a moderate depth of 1-sigma ~ 4 mJy/beam. This is the largest contiguous area of extragalactic sky mapped by JCMT at 850um to date. The wide area of the S2LXS XMM-LSS survey allows us to probe the ultra-bright (S_850um > 15 mJy), yet rare submillimetre population. We present the S2LXS XMM-LSS catalogue, which comprises 40 sources detected at >5-sigma significance, with deboosted flux densities in the range of 7 mJy to 48 mJy. We robustly measure the bright-end of the 850um number counts at flux densities >7 mJy, reducing the Poisson errors compared to existing measurements. The S2LXS XMM-LSS observed number counts show the characteristic upturn at bright fluxes, expected to be motivated by local sources of submillimetre emission and high-redshift strongly lensed galaxies. We find that the observed 850um number counts are best reproduced by model predictions that include either strong lensing or source blending from a 15 arcsec beam, indicating that both may make an important contribution to the observed over-abundance of bright single dish 850um selected sources. We make the S2LXS XMM-LSS 850um map and >5-sigma catalogue presented here publicly available.
Comment: Accepted for publication in MNRAS
Comment: Accepted for publication in MNRAS