THE CHANDRA COSMOS LEGACY SURVEY: CLUSTERING of X-RAY-SELECTED AGNs at 2.9 ≤ z ≤ 5.5 USING PHOTOMETRIC REDSHIFT PROBABILITY DISTRIBUTION FUNCTIONS

We present the measurement of the projected and redshift-space two-point correlation function (2pcf) of the new catalog of Chandra COSMOS-Legacy active galactic nucleus (AGN) at 2.9 ≤ z ≤ 5.5 ( 10⁴⁶erg s^-1) using the generalized clustering estimator based on phot-z probability distribution functions in addition to any available spec-z. We model the projected 2pcf, estimated using π _max = 200 h^-1 Mpc with the two-halo term and we derive a bias at z ∼ 3.4 equal to b = , which corresponds to a typical mass of the hosting halos of log M _h = h^-1 M _o. A similar bias is derived using the redshift-space 2pcf, modeled including the typical phot-z error σ _z = 0.052 of our sample at z ≥ 2.9. Once we integrate the projected 2pcf up to π _max = 200 h^-1 Mpc, the bias of XMM and Chandra COSMOS at z = 2.8 used in Allevato et al. is consistent with our results at higher redshifts. The results suggest only a slight increase of the bias factor of COSMOS AGNs at z 3 with the typical hosting halo mass of moderate-luminosity AGNs almost constant with redshift and equal to log M _h = at z = 2.8 and log M _h = at z ∼ 3.4, respectively. The observed redshift evolution of the bias of COSMOS AGNs implies that moderate-luminosity AGNs still inhabit group-sized halos at z 3, but slightly less massive than observed in different independent studies using X-ray AGNs at z ≤ 2.