Dusty Universe viewed by AKARI far infrared detector

K. Malek , A. Pollo , T. T. Takeuchi , E. Giovannoli , V. Buat (1) , D. Burgarella (1) , M. Malkan , A. Kurek

1 LAM - Laboratoire d'Astrophysique de Marseille

We present the results of the analysis of multiwavelength Spectral Energy Distributions (SEDs) of far-infrared galaxies detected in the AKARI Deep Field-South (ADF-S) Survey. The analysis uses a carefully selected sample of 186 sources detected at the 90 mu m AKARI band, identified as galaxies with cross-identification in public catalogues. For sources without known spectroscopic redshifts, we estimate photometric redshifts after a test of two independent methods: one based on using mainly the optical-mid infrared range, and one based on the whole range of ultraviolet-far infrared data. We observe a vast improvement in the estimation of photometric redshifts when far infrared data are included, compared with an approach based mainly on the optical-mid infrared range. We discuss the physical properties of our far-infrared-selected sample. We conclude that this sample consists mostly of rich in dust and young stars nearby galaxies, and, furthermore, that almost 25% of these sources are (Ultra) Luminous Infrared Galaxies. Average SEDs normalized at 90 mu m for normal galaxies (138 sources), LIRGs (30 sources), and ULIRGs (18 galaxies) show a significant shift in the peak wavelength of the dust emission, and an increasing ratio between their bolometric and dust luminosities which varies from 0.39 to 0.73.

Domaines: Astrophysique [astro-ph]

K. Malek, A. Pollo, T. T. Takeuchi, E. Giovannoli, V. Buat, et al.. Dusty Universe viewed by AKARI far infrared detector. Earth Planets and Space, 2013, 65 (10), pp.1101--1108. ⟨10.5047/eps.2013.06.005⟩. ⟨hal-01439553⟩