Euclid Quick Data Release (Q1). The active galaxies of Euclid
Collaboration
Citations per year
0 Citations
Abstract: (arXiv)
We present a catalogue of candidate active galactic nuclei (AGN) in the Quick Release (Q1) fields. For each source we collect multi-wavelength photometry and spectroscopy information from Galaxy Evolution Explorer (GALEX), , Dark Energy Survey (DES), Wise-field Infrared Survey Explorer (WISE), , Dark Energy Survey (DESI), and Sloan Digital Sky Survey (SDSS), including spectroscopic redshift from public compilations. We investigate the AGN contents of the Q1 fields by applying selection criteria using colours and WISE-AllWISE cuts finding respectively 292,222 and 65,131 candidates. We also create a high-purity QSO catalogue based on DR3 information containing 1971 candidates. Furthermore, we utilise the collected spectroscopic information from DESI to perform broad-line and narrow-line AGN selections, leading to a total of 4392 AGN candidates in the Q1 field. We investigate and refine the Q1 probabilistic random forest QSO population, selecting a total of 180,666 candidates. Additionally, we perform SED fitting on a subset of sources with available , and by utilizing the derived AGN fraction, we identify a total of 7766 AGN candidates. We discuss purity and completeness of the selections and define two new colour selection criteria (_ and _) to improve on purity, finding 313,714 and 267,513 candidates respectively in the Q1 data. We find a total of 229,779 AGN candidates equivalent to an AGN surface density of 3641 deg for , and a subsample of 30,422 candidates corresponding to an AGN surface density of 482 deg when limiting the depth to . The surface density of AGN recovered from this work is in line with predictions based on the AGN X-ray luminosity functions.Note:
- Paper submitted as part of the A&A Special Issue "Euclid Quick Data Release (Q1)", 30 pages, 20 figures
References(599)
Figures(19)