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arXiv · astro-ph/0403645

Colors of AGN host galaxies at 0.5<z<1.1 from GEMS

S. F. Sanchez·K. Jahnke·L. Wisotzki·D. H. McIntosh·E. F. Bell·M. Barden·S. V. W. Beckwith·A. Borch·J. A. R. Caldwell·B. Haeussler·S. Jogee·K. Meisenheimer·C. Y. Peng·H. -W. Rix·R. S. Somerville·C. Wolf
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Abstract

We present the results from a study of the host galaxies of 15 optically selected AGNs with 0.5<z<1.1 from GEMS. GEMS is a Hubble Space Telescope imaging survey of a ~28"x28" contiguous field centered on the Chandra Deep Field South in the F606W and F850LP filter bands. It incorporates the SEDs and redshifts of ~10000 objects, obtained by the COMBO-17 project. We have detected the host galaxies of all 15 AGNs in the F850LP-band (and 13/15 in the F606W-band), recovering their fluxes, morphologies and structural parameters. We find that 80% of the host galaxies have early-type (bulge-dominated) morphologies, while the rest have structures characteristic of late-type (disk-dominated) galaxies. We find that 25% of the early types, and 30% of the late types, exhibit disturbances consistent with galaxy interactions. The hosts show a wide range of colors, from those of red-sequence galaxies to blue colors consistent with ongoing star formation. Roughly 70% of the morphologically early-type hosts have rest-frame blue colors, a much larger fraction than those typical of non-active morphologically early-type galaxies in this redshift and luminosity range. Yet, we find that the early-type hosts are structurally similar to red-sequence ellipticals, inasmuch as they follow an absolute magnitude versus half-light size correlation that are consistent with the mean relation for early-type galaxies at similar redshifts.

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S. F. Sanchez, K. Jahnke, L. Wisotzki, D. H. McIntosh, E. F. Bell, M. Barden, S. V. W. Beckwith, A. Borch, J. A. R. Caldwell, B. Haeussler, S. Jogee, K. Meisenheimer, C. Y. Peng, H. -W. Rix, R. S. Somerville, C. Wolf. 2004-06-14. Colors of AGN host galaxies at 0.5<z<1.1 from GEMS. https://doi.org/10.1086/423234

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