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arXiv · 1002.3618

The AGN fraction of submm-selected galaxies and contributions to the submm/mm-wave extragalactic background light

S. Serjeant·M. Negrello·C. Pearson·A. Mortier·J. Austermann·I. Aretxaga·D. Clements·S. Chapman·S. Dye·J. Dunlop·L. Dunne·D. Farrah·D. Hughes·H. -M. Lee·H. Matsuhara·E. Ibar·M. Im·W. -S. Jeong·S. Kim·S. Oyabu·T. Takagi·T. Wada·G. Wilson·M. Vaccari·M. Yun
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Abstract

We present a comparison of the SCUBA Half Degree Extragalactic Survey (SHADES) at 450, 850 and 1100 microns with deep guaranteed time 15 microns AKARI FU-HYU survey data and Spitzer guaranteed time data at 3.6-24 microns in the Lockman Hole East. The AKARI data was analysed using bespoke software based in part on the drizzling and minimum-variance matched filtering developed for SHADES, and was cross calibrated against Infrared Space Observatory (ISO) fluxes. Our stacking analyses find AKARI 15um galaxies with >~200 microJy contribute >10% of the 450 micron background, but only <4% of the 1100 micron background, suggesting that different populations contribute at mm-wavelengths. We confirm our earlier result that the ultra-deep 450 micron SCUBA-2 Cosmology Survey will be dominated by populations already detected by AKARI and Spitzer mid-infrared surveys. The superb mid-infrared wavelength coverage afforded by combining Spitzer and AKARI photometry is an excellent diagnostic of AGN contributions, and we find that (23-52)% of submm-selected galaxies have AGN bolometric fractions f_AGN>0.3.

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S. Serjeant, M. Negrello, C. Pearson, A. Mortier, J. Austermann, I. Aretxaga, D. Clements, S. Chapman, S. Dye, J. Dunlop, L. Dunne, D. Farrah, D. Hughes, H. -M. Lee, H. Matsuhara, E. Ibar, M. Im, W. -S. Jeong, S. Kim, S. Oyabu, T. Takagi, T. Wada, G. Wilson, M. Vaccari, M. Yun. 2010-02-18. The AGN fraction of submm-selected galaxies and contributions to the submm/mm-wave extragalactic background light. https://doi.org/10.1051/0004-6361/200913483

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