AzTEC millimetre survey of the COSMOS field – III. Source catalogue over 0.72 deg² and plausible boosting by large-scale structure
We present a 0.72 deg² contiguous 1.1-mm survey in the central area of the Cosmological Evolution Survey field carried out to a 1σ ≈ 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-nois...
| Autores: | , |
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| Tipo de recurso: | artículo |
| Estado: | Versión aceptada para publicación |
| Fecha de publicación: | 2011 |
| País: | México |
| Institución: | Instituto Nacional de Astrofísica, Óptica y Electrónica |
| Repositorio: | Repositorio Institucional del INAOE |
| Idioma: | inglés |
| OAI Identifier: | oai:inaoe.repositorioinstitucional.mx:1009/1801 |
| Acceso en línea: | http://inaoe.repositorioinstitucional.mx/jspui/handle/1009/1801 |
| Access Level: | acceso abierto |
| Palabra clave: | info:eu-repo/classification/Inspec/Surveys – Galaxies info:eu-repo/classification/Inspec/Evolution – Cosmology info:eu-repo/classification/Inspec/Miscellaneous – S ubmillimetre info:eu-repo/classification/Inspec/Galaxies info:eu-repo/classification/cti/1 info:eu-repo/classification/cti/21 |
| Sumario: | We present a 0.72 deg² contiguous 1.1-mm survey in the central area of the Cosmological Evolution Survey field carried out to a 1σ ≈ 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 (≲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 ∼0.5 deg² 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 S₁.₁ₘₘ ≳ 5mJy regime, and demonstrate that these excesses in number counts are related to the areas where galaxies at redshifts z≲ 1.1 are more densely clustered. The positions of optical–infrared galaxies in the redshift interval 0.6 ≲ z≲ 0.75 are the ones that show the strongest correlation with the positions of the 1.1-mm bright population (S₁.₁ₘₘ ≳ 5mJy ), a result which does not depend exclusively on the presence of rich clusters within the survey sampled area. Themost 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. |
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