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arXiv · 1910.08084

The Chandra COSMOS Legacy Survey: clustering dependence of Type 2 AGN on host galaxy properties

V. Allevato·A. Viitanen·A. Finoguenov·F. Civano·H. Suh·F. Shankar·A. Bongiorno·A. Ferrara·R. Gilli·T. Miyaji·S. Marchesi·N. Cappelluti·M. Salvato
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Abstract

Aims. We perform clustering measurements of 800 X-ray selected Chandra COSMOS Legacy (CCL) Type 2 AGN with known spectroscopic redshift to probe the halo mass dependence on AGN host galaxy properties, such as galaxy stellar mass Mstar, star formation rate (SFR) and specific black hole accretion rate (BHAR), in the redshift range z = [0 - 3]. Methods. We split the sample of AGN with known spectroscopic redshits according to Mstar, SFR and specific BHAR, while matching the distributions in terms of the other parameters, including redshift. We measure the projected two-point correlation function wp(rp) and model it with the 2-halo term to derive the large-scale bias b and the corresponding typical mass of the hosting halo, for the different subsamples. Results. We found no significant dependence of the large-scale bias and typical halo mass on galaxy stellar mass and specific BHAR for CCL Type 2 AGN at mean z~1, while a negative dependence on SFR is observed, with lower SFR AGN residing in richer environment. Mock catalogs of AGN matched to have the same X-ray luminosity, stellar mass, specific BHAR and SFR of CCL Type 2 AGN, almost reproduce the observed Mstar, specific BHAR and SFR-Mh relations, when assuming a fraction of satellite AGN of 15%, which corresponds to a ratio between the probabilities of satellite and central AGN of being active Q = 2. Mock matched normal galaxies follow a slightly steeper Mstar -Mh relation with low mass mock galaxies residing in less massive halos than mock AGN of similar mass, and are less biased than mock AGN with similar specific BHAR and SFR, at least for Q > 1.

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V. Allevato, A. Viitanen, A. Finoguenov, F. Civano, H. Suh, F. Shankar, A. Bongiorno, A. Ferrara, R. Gilli, T. Miyaji, S. Marchesi, N. Cappelluti, M. Salvato. 2019-10-17. The Chandra COSMOS Legacy Survey: clustering dependence of Type 2 AGN on host galaxy properties. https://doi.org/10.1051/0004-6361/201936191

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