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arXiv · 0911.5598

Star forming galaxies in the AKARI Deep Field South: identifications and SEDs

K. Malek·A. Pollo·T. T. Takeuchi·P. Bienias·M. Shirahata·S. Matsuura·M. Kawada
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Abstract

To investigate the nature and properties of far-infrared (FIR) sources from the AKARI Deep Field South (ADF-S), we performed an extensive search for the counterparts of 1000 ADF-S objects brighter than 0.0301 Jy in the WIDE-S (90 $\mu$m) AKARI band in the public databases (NED and SIMBAD). We analyzed the properties of the resulting sample: statistic of the identified objects, number counts, redshift distribution and morphological types. We also made a crude analysis of the clustering properties of the sources and constructed spectral energy distributions (SEDs) of 47 selected objects with the best photometry. Among 1000 investigated ADF-S sources, 545 were identified at other wavelengths. From them, 518 are known galaxies, and 343 of them were not known previously as infra-red sources. We found redshifts of 48 extragalactic objects and morphological types of 77 galaxies. We conclude that the bright FIR point sources observed in the ADF-S are mostly nearby galaxies.Their properties are very similar to properties of the local population of optically bright galaxies, except an unusually high ratio of peculiar or interacting objects and a smaller percentage of elliptical galaxies. The percentage of lenticular galaxies is the same as in the optically bright population which suggests they may frequently contain a significant amount of cool dust. It is possible that source confusion plays a significant role in more than 34% of measurements. The SEDs display a variety of galaxy types, from very actively star forming to very quiescent. Thanks to the AKARI long wavelength bands it was revealed for the first time that these galaxies form a population of objects with very cool dust.

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K. Malek, A. Pollo, T. T. Takeuchi, P. Bienias, M. Shirahata, S. Matsuura, M. Kawada. 2009-11-30. Star forming galaxies in the AKARI Deep Field South: identifications and SEDs. https://doi.org/10.1051/0004-6361/200913419

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