X-ray spectroscopic survey of highly-accreting AGN

Autor: M. Bischetti, A. Luminari, M. Laurenti, Simone Bianchi, Angela Bongiorno, G. Vietri, A. del Olmo, Paola Marziani, Giorgio Lanzuisi, R. Middei, M. Perri, Francesco Tombesi, Claudio Ricci, Cristian Vignali, Enrico Piconcelli, Luca Zappacosta, F. Vagnetti
Přispěvatelé: Laurenti M., Piconcelli E., Zappacosta L., Tombesi F., Vignali C., Bianchi S., Marziani P., Vagnetti F., Bongiorno A., Bischetti M., Del Olmo A., Lanzuisi G., Luminari A., Middei R., Perri M., Ricci C., Vietri G., Laurenti, M., Piconcelli, E., Zappacosta, L., Tombesi, F., Vignali, C., Bianchi, S., Marziani, P., Vagnetti, F., Bongiorno, A., Bischetti, M., del Olmo, A., Lanzuisi, G., Luminari, A., Middei, R., Perri, M., Ricci, C., Vietri, G., European Commission, Ministerio de Ciencia e Innovación (España), Ministero dell'Istruzione, dell'Università e della Ricerca, Istituto Nazionale di Astrofisica
Jazyk: angličtina
Rok vydání: 2022
Předmět:
Active galactic nucleus
active [Galaxies]
Astrophysics::High Energy Astrophysical Phenomena
astro-ph.GA
quasars
Quasars: supermassive black holes
FOS: Physical sciences
active
Astrophysics
Astrophysics::Cosmology and Extragalactic Astrophysics
Lambda
Luminosity
Bolometric correction
galaxies
quasar
Continuum (set theory)
Astrophysics::Galaxy Astrophysics
Physics
High Energy Astrophysical Phenomena (astro-ph.HE)
astro-ph.HE
Accretion (meteorology)
Settore FIS/05
galaxie
supermassive black holes
Order (ring theory)
general [Quasars]
Astronomy and Astrophysics
Galaxies: active
Astrophysics - Astrophysics of Galaxies
Quasars: general
Black hole
Space and Planetary Science
general
Astrophysics of Galaxies (astro-ph.GA)
Astrophysics - High Energy Astrophysical Phenomena
supermassive black holes [Quasars]
Zdroj: Digital.CSIC. Repositorio Institucional del CSIC
instname
Popis: Improving our understanding of the nuclear properties of high-Eddington-ratio (λEdd) active galactic nuclei (AGN) is necessary since at this regime the radiation pressure is expected to affect the structure and efficiency of the accretion disc-corona system. This may cause departures from the typical nuclear properties of low-λEdd AGN, which have been largely studied so far. We present here the X-ray spectral analysis of 14 radio-quiet, λEdd ≳ 1 AGN at 0.4 ≤ z ≤ 0.75, observed with XMM-Newton. Optical/UV data from simultaneous Optical Monitor observations have also been considered. These quasars were selected to have relatively high values of black hole mass (MBH ∼ 108 − 8.5 M⊙) and bolometric luminosity (Lbol ∼ 1046 erg s−1) in order to complement previous studies of high-λEdd AGN at lower MBH and Lbol. We studied the relation between λEdd and other key X-ray spectral parameters, such as the photon index (Γ) of the power-law continuum, the X-ray bolometric correction (kbol, X), and the optical/UV-to-X-ray spectral index (αox). Our analysis reveals that, despite the homogeneous optical and supermassive black hole accretion properties, the X-ray properties of these high-λEdd AGN are quite heterogeneous. We indeed measured values of Γ between 1.3 and 2.5, at odds with the expectations based on previously reported Γ − λEdd relations, for which Γ ≥ 2 would be a ubiquitous hallmark of AGN with λEdd ∼ 1. Interestingly, we found that ∼30% of the sources are X-ray weak, with an X-ray emission about a factor of ∼10 − 80 fainter than that of typical AGN at similar UV luminosities. The X-ray weakness seems to be intrinsic and not due to the presence of absorption along the line of sight to the nucleus. This result may indicate that high-λEdd AGN commonly undergo periods of intrinsic X-ray weakness. Furthermore, results from follow-up monitoring with Swift of one of these X-ray weak sources suggest that these periods can last for several years. © ESO 2022.
This work is based on observations obtained with XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA. Part of this work is based on archival data, software and online services provided by the Space Science Data Center – ASI. This work has been partially supported by the ASI-INAF program I/004/11/4. ML acknowledges financial support from the PhD programme in Astronomy, Astrophysics and Space Science supported by MIUR (Ministero dell’Istruzione, dell’Università e della Ricerca). EP, LZ, FT, SB, AL and GV acknowledge financial support under ASI/INAF contract 2017-14-H.0. EP, SB, MB and GV acknowledge support from PRIN MIUR project “Black Hole winds and the Baryon Life Cycle of Galaxies: the stone-guest at the galaxy evolution supper”, contract #2017PH3WAT. AdO acknowledges financial support from the State Agency for Research of the Spanish MCIU through the project PID2019-106027GB-C41 and the “Center of Excellence Severo Ochoa” award to the Instituto de Astrofísica de Andalucía (SEV-2017-0709). RM acknowledges the financial support of INAF (Istituto Nazionale di Astrofisica), Osservatorio Astronomico di Roma, ASI (Agenzia Spaziale Italiana) under contract to INAF: ASI 2014-049-R.0 dedicated to SSDC. CR acknowledges support from the Fondecyt Iniciacion grant 11190831.
Databáze: OpenAIRE
Externí odkaz: