AzTEC millimetre survey of the COSMOS field - III. Source catalogue over 0.72 deg(2) and plausible boosting by large-scale structure

作者：Aretxaga I^*; Wilson G W; Aguilar E; Alberts S; Scott K S; Scoville N; Yun M S; Austermann J; Downes T P; Ezawa H; Hatsukade B; Hughes D H; Kawabe R; Kohno K; Oshima T; Perera T A; Tamura Y; Zeballos M

来源：Monthly Notices of the Royal Astronomical Society, 2011, 415(4): 3831-3850.

DOI：10.1111/j.1365-2966.2011.18989.x

• surveys
• galaxies: evolution
• cosmology: miscellaneous
• submillimetre: galaxies

We present a 0.72 deg(2) contiguous 1.1-mm survey in the central area of the Cosmological Evolution Survey field carried out to a 1 sigma approximate to 1.26 mJy beam(-1) depth with the AzTEC camera mounted on the 10-m Atacama Submillimeter Telescope Experiment. We have uncovered 189 candidate sources at a signal-to-noise ratio (S/N) >= 3.5, out of which 129, with S/N >= 4, can be considered to have little chance of being spurious (less than or similar to 2 per cent). We present the number counts derived with this survey, which show a significant excess of sources when compared to the number counts derived from the similar to 0.5 deg(2) area sampled at similar depths in the Submillimetre Common-User Bolometer Array (SCUBA) HAlf Degree Extragalactic Survey (SHADES). They are, however, consistent with those derived from fields that were considered too small to characterize the overall blank-field population. We identify differences to be more significant in the S-1.1mm greater than or similar to 5mJy regime, and demonstrate that these excesses in number counts are related to the areas where galaxies at redshifts z less than or similar to 1.1 are more densely clustered. The positions of optical-infrared galaxies in the redshift interval 0.6 less than or similar to z less than or similar to 0.75 are the ones that show the strongest correlation with the positions of the 1.1-mm bright population (S-1.1mm greater than or similar to 5 mJy), a result which does not depend exclusively on the presence of rich clusters within the survey sampled area. The most likely explanation for the observed excess in number counts at 1.1-mm is galaxy-galaxy and galaxy-group lensing at moderate amplification levels, which increases in amplitude as one samples larger and larger flux densities. This effect should also be detectable in other high-redshift populations.

• 出版日期2011-8
• 单位中国科学院国家天文台