2024-03-28T12:04:50Zhttp://digital.csic.es/dspace-oai/requestoai:digital.csic.es:10261/1700782020-12-13T09:13:23Zcom_10261_37com_10261_4col_10261_290
Mountrichas, George
Georgantopoulos, I.
Ordovás-Pascual, I.
Corral, Amalia
Akylas, A.
Mateos, Silvia
Carrera, Francisco J.
Batziou, E.
2018-09-24T08:57:17Z
2018-09-24T08:57:17Z
2017
Monthly Notices of the Royal Astronomical Society 468(3): 3042-3050 (2017)
http://hdl.handle.net/10261/170078
10.1093/mnras/stx572
http://dx.doi.org/10.13039/501100003329
http://dx.doi.org/10.13039/100000879
http://dx.doi.org/10.13039/501100000780
http://dx.doi.org/10.13039/100000001
http://dx.doi.org/10.13039/100000015
Mid-infrared (IR) colour selection techniques have proved to be very efficient in finding active galactic nuclei (AGN). This is because the AGN heats the surrounding dust producing warm mid-IR colours. Using the Wide-field Infrared Survey Explorer 3.6, 4.5 and 12 μm colours, the largest sample of IR selected AGN has already been produced containing 1.4 million AGN over the whole sky. Here, we explore the X-ray properties of this AGN sample by cross-correlating it with the subsample of the 3XMM X-ray catalogue that has available X-ray spectra and at the same time optical spectroscopy from Sloan Digital Sky Survey (SDSS). Our goal is to find rare luminous obscured AGN. Our final sample contains 65 QSOs with log νLν ≥ 46.2 erg s−1. This IR luminosity cut corresponds to log LX ≈ 45 erg s−1, at the median redshift of our sample (z = 2.3), that lies at the bright end of the X-ray luminosity function at z > 2. The X-ray spectroscopic analysis reveals seven obscured AGN having a column density NH > 1022 cm−2. Six of them show evidence for broad [C IV] absorption lines and five are classified as broad absorption line QSOs. We fit the optical spectra of our X-ray absorbed sources to estimate the optical reddening. We find that none of these show any obscuration according to the optical continuum. These sources add to the growing evidence for populations of luminous QSOs with evidence for substantial absorption by outflowing ionized material, similar to those expected to be emerging from their absorbing cocoons in the framework of AGN/galaxy co-evolution.
eng
openAccess
Black hole physics
Galaxies: Seyfert
Galaxies: haloes
Quasars: general
Galaxies: active
Searching for luminous absorbed sources in the WISE AGN catalogue
artículo