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arXiv · 1005.2562

Star formation in AGN hosts in GOODS-N

Abstract

Sensitive Herschel far-infrared observations can break degeneracies that were inherent to previous studies of star formation in high-z AGN hosts. Combining PACS 100 and 160um observations of the GOODS-N field with 2Msec Chandra data, we detect ~20% of X-ray AGN individually at >3sig. The host far-infrared luminosity of AGN with L2-10~10^43erg/s increases with redshift by an order of magnitude from z=0 to z~1. In contrast, there is little dependence of far-infrared luminosity on AGN luminosity, for L2-10<~10^44erg/s AGN at z>~1. We do not find a dependence of far-infrared luminosity on X-ray obscuring column, for our sample which is dominated by L2-10<10^44erg/s AGN. In conjunction with properties of local and luminous high-z AGN, we interpret these results as reflecting the interplay between two paths of AGN/host coevolution. A correlation of AGN luminosity and host star formation is traced locally over a wide range of luminosities and also extends to luminous high z AGN. This correlation reflects an evolutionary connection, likely via merging. For lower AGN luminosities, star formation is similar to that in non-active massive galaxies and shows little dependence on AGN luminosity. The level of this secular, non-merger driven star formation increasingly dominates over the correlation at increasing redshift.

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BibTeXRIS

L. Shao, D. Lutz, R. Nordon, R. Maiolino, D. M. Alexander, B. Altieri, P. Andreani, H. Aussel, F. E. Bauer, S. Berta, A. Bongiovanni, W. N. Brandt, M. Brusa, A. Cava, J. Cepa, A. Cimatti, E. Daddi, H. Dominguez-Sanchez, D. Elbaz, N. M. Forster Schreiber, N. Geis, R. Genzel, A. Grazian, C. Gruppioni, G. Magdis, B. Magnelli, V. Mainieri, A. M. Perez Garcia, A. Poglitsch, P. Popesso, F. Pozzi, L. Riguccini, G. Rodighiero, E. Rovilos, A. Saintonge, M. Salvato, M. Sanchez Portal, P. Santini, E. Sturm, L. J. Tacconi, I. Valtchanov, M. Wetzstein, E. Wieprecht. 2010-05-14. Star formation in AGN hosts in GOODS-N. https://doi.org/10.1051/0004-6361/201014606

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