Plionis, M.M.PlionisKoutoulidis, L.L.KoutoulidisKoulouridis, E.E.KoulouridisMoscardini, L.L.MoscardiniLidman, C.C.LidmanPierre, M.M.PierreAdami, C.C.AdamiCHIAPPETTI, LUCIOLUCIOCHIAPPETTIFaccioli, L.L.FaccioliFotopoulou, S.S.FotopoulouPacaud, F.F.PacaudPaltani, S.S.Paltani2020-10-052020-10-0520180004-6361http://hdl.handle.net/20.500.12386/27590The XMM-XXL Survey spans two fields of 25 deg<SUP>2</SUP> each observed for more than 6 Ms with XMM, which provided a sample of tens of thousands of point sources with a flux limit of 2.2 × 10<SUP>-15</SUP> and 1.4 × 10<SUP>-14</SUP> erg s<SUP>-1</SUP> cm<SUP>2</SUP>, corresponding to 50% of the area curve, in the soft band (0.5-2 keV) and hard band (2-10 keV), respectively. In this paper we present the spatial clustering properties of 3100 and 1900 X-ray active galactic nuclei (AGNs) in the soft and hard bands, respectively, which have been spectroscopically observed with the AAOmega facility. This sample is 90% redshift complete down to an optical magnitude limit of r ≲ 21.8. The sources span the redshift interval 0 < z < 5.2, although in the current analysis we limit our samples to z ≤ 3, with corresponding sample median values of z̅ ≃ 0.96 and 0.79 for the soft band and hard band, respectively. We employ the projected two-point correlation function to infer the spatial clustering and find a correlation length r<SUB>0</SUB> = 7.0(±0.34) and 6.42(±0.42) h<SUP>-1</SUP> Mpc, respectively, for the soft- and hard-band detected sources with a slope for both cases of γ = 1.44(±0.1). The power-law clustering was detected within comoving separations of 1 and 25 h<SUP>-1</SUP> Mpc. These results, as well as those derived in two separate redshift ranges, provide bias factors of the corresponding AGN host dark matter halos that are consistent with a halo mass of log<SUB>10</SUB>[M<SUB>h</SUB>/(h<SUP>-1</SUP>M<SUB>☉</SUB>)] = 13.04 ± 0.06, confirming the results of most recent studies based on smaller X-ray AGN samples. <P />Based on observations obtained with XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA.STAMPAenArticle10.1051/0004-6361/2018329702-s2.0-85057344452000450930100017https://www.aanda.org/articles/aa/full_html/2018/12/aa32970-18/aa32970-18.htmlhttps://arxiv.org/abs/1804.064092018A&A...620A..17PFIS/05 - ASTRONOMIA E ASTROFISICAERC sectors::Physical Sciences and Engineering::PE9 Universe sciences: astro-physics/chemistry/biology; solar systems; stellar, galactic and extragalactic astronomy, planetary systems, cosmology, space science, instrumentation