Host galaxy properties of X-ray active galactic nuclei in the local Universe

We study the host galaxy properties of active galactic nuclei (AGN) that have been detected in X-rays in the nearby Universe (z < 0.2). For that purpose, we use the catalogue provided by the ROSAT-2RXS in the 0.1–2.4 keV energy band, one of the largest X-ray datasets with spectroscopic observatio...

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Detalles Bibliográficos
Autores: Koutoulidis, L., Mountrichas, George, Georgantopoulos, Ioannis, Pouliasis, Ektoras, Plionis, Manolis
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2022
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/279951
Acceso en línea:http://hdl.handle.net/10261/279951
Access Level:acceso abierto
Palabra clave:Galaxies: nuclei
X-ray galaxies
Methods: data analysis
Galaxies: active
Methods: observational
Galaxies: star formation
Descripción
Sumario:We study the host galaxy properties of active galactic nuclei (AGN) that have been detected in X-rays in the nearby Universe (z < 0.2). For that purpose, we use the catalogue provided by the ROSAT-2RXS in the 0.1–2.4 keV energy band, one of the largest X-ray datasets with spectroscopic observations. Our sample consists of ∼900 X-ray AGN. The catalogue provides classification of the sources into type 1 and 2 based on optical spectra. Approximately 25% of the AGN are type 2. We use the available optical, near-IR, and mid-IR photometry to construct spectral energy distributions (SEDs). We measure the stellar mass (M*) and star formation rate (SFR) of the AGN by fitting these SEDs with the X-CIGALE code. We compare the M* and SFR of the two AGN populations, taking their different redshift and luminosity distributions into account. Based on our results, type 2 AGN tend to live in more massive galaxies compared to their type 1 counterparts (log [M∗(M⊙)] = 10.49−0.10+0.16 vs. 10.23−0.08+0.05), in agreement with previous studies at higher redshifts. In terms of SFRs, our analysis shows that, in the nearby Universe, the number of X-ray AGN that live in quiescent systems is higher compared to at higher redshifts, in accordance with previous studies in the local Universe. However, the majority of AGN (∼75%) live inside or above the main sequence.