The XMM-Newton wide field survey in the COSMOS field: Clustering dependence of X-ray selected AGN on host galaxy properties

A. Viitanen, V. Allevato, A. Finoguenov, A. Bongiorno, N. Cappelluti, R. Gilli, T. Miyaji, M. Salvato, G. Hasinger, M. Brusa
2019 Astronomy and Astrophysics  
We study the spatial clustering through the projected two-point correlation function of 632(1130) XMM-COSMOS Active Galactic Nuclei (AGNs) with known spectroscopic (spectroscopic or photometric) redshifts in the range z = [0.1 - 2.5] in order to measure the AGN bias and estimate the typical mass of the hosting dark matter (DM) halo as a function of AGN host galaxy properties. We create AGN subsamples in terms of stellar mass M_* and specific black hole accretion rate L_X/M_*, to probe how AGN
more » ... vironment depends on these quantities. For the full spectroscopic AGN sample, we measure a typical DM halo mass of log (M_halo / h^-1M_)= 12.79_-0.43^+0.26, similar to galaxy group environments and in line with previous studies for moderate-luminosity X-ray selected AGN. We find no significant dependence on L_X/M_*, with log (M_halo / h^-1M_) = 13.06_-0.38^+0.23 (12.97_-1.26^+0.39) for the low (high) L_X/M_* subsample. We also find no difference in the hosting halos in terms of M_* with log (M_halo / h^-1M_) = 12.93_-0.62^+0.31 (12.90_-0.62^+0.30) for the low (high) M_* subsample. By comparing the M_*-M_halo relation derived for XMM-COSMOS AGN subsamples with what is expected for normal non-active galaxies by abundance matching and clustering results, we find that the typical DM halo mass of our high M_* AGN subsample is similar to that of non-active galaxies. However, AGNs in our low M_* subsample are found in more massive halos than non-active galaxies. By excluding AGNs in galaxy groups from the clustering analysis, we find evidence that the result for low M_* may be due a larger fraction of AGNs as satellites in massive halos.
doi:10.1051/0004-6361/201935186 fatcat:vhztyj6kznfw5atigir5dpph4y