Black hole virial masses from single-epoch photometry

The miniJPAS test case

¹ Donostia International Physics Center, Paseo Manuel de Lardizabal 4, 20018 Donostia-San Sebastian, Spain
e-mail: jonas.chaves@dipc.org
² Ikerbasque, Basque Foundation for Science, 48013 Bilbao, Spain
³ School of Physics and Astronomy, Tel Aviv University, Tel Aviv 69978, Israel
⁴ Facultad de Ciencias Físicas, Universidad Complutense de Madrid, Plaza de Ciencias, 1, 28040 Madrid, Spain
⁵ Departamento de Astronomia, Instituto de Física, Universidade Federal do Rio Grande do Sul (UFRGS), Av. Bento Gonçalves, 9500 Porto Alegre, RS, Brazil
⁶ Instituto de Física, Universidade de São Paulo, Rua do Matão 1371, CEP 05508-090 São Paulo, Brazil
⁷ Instituto de Astrofísica de Andalucía (CSIC), PO Box 3004 18080 Granada, Spain
⁸ Centro de Estudios de Física del Cosmos de Aragón (CEFCA), Plaza San Juan, 1, 44001 Teruel, Spain
⁹ Instituto de Astrofísica de Canarias, Calle Vía Láctea s/n, 38205 La Laguna, Spain
¹⁰ Departamento de Astrofísica, Universidad de La Laguna, 38205 La Laguna, Spain
¹¹ Centro de Estudios de Física del Cosmos de Aragón (CEFCA), Unidad Asociada al CSIC, Plaza San Juan, 1, 44001 Teruel, Spain
¹² Observatório Nacional/MCTIC, Rua General José Cristino, 77, São Cristóvão, Rio de Janeiro, RJ, 20921-400, Brazil
¹³ Institute of Astronomy, Geophysics and Atmospheric Sciences, University of São Paulo, Rua do Matão, 1226, São Paulo, SP 05508-090, Brazil
¹⁴ Department of Physics, Lancaster University, Lancaster LA1 4YB, UK
¹⁵ Instituto de Física, Universidade Federal da Bahia, 40210-340 Salvador, BA, Brazil
¹⁶ Department of Astronomy, University of Michigan, 311 West Hall, 1085 South University Ave., Ann Arbor, USA
¹⁷ University of Alabama, Department of Physics and Astronomy, Gallalee Hall, Tuscaloosa, AL 35401, USA
¹⁸ Instruments4, 4121 Pembury Place, La Canada Flintridge, CA 91011, USA

Received: 2 November 2021
Accepted: 26 January 2022

Abstract

Context. Precise measurements of black hole masses are essential to understanding the coevolution of these sources and their host galaxies.

Aims. We develop a novel approach for computing black hole virial masses using measurements of continuum luminosities and emission line widths from partially overlapping, narrow-band observations of quasars; we refer to this technique as single-epoch photometry.

Methods. This novel method relies on forward-modelling quasar observations for estimating emission line widths, which enables unbiased measurements even for lines coarsely resolved by narrow-band data. We assess the performance of this technique using quasars from the Sloan Digital Sky Survey (SDSS) observed by the miniJPAS survey, a proof-of-concept project of the Javalambre Physics of the Accelerating Universe Astrophysical Survey (J-PAS) collaboration covering ≃1 deg² of the northern sky using the 56 J-PAS narrow-band filters.

Results. We find remarkable agreement between black hole masses from single-epoch SDSS spectra and single-epoch miniJPAS photometry, with no systematic difference between these and a scatter ranging from 0.4 to 0.07 dex for masses from log(M_BH)≃8 to 9.75, respectively. Reverberation mapping studies show that single-epoch masses present approximately 0.4 dex precision, letting us conclude that our novel technique delivers black hole masses with only mildly lower precision than single-epoch spectroscopy.

Conclusions. The J-PAS survey will soon start observing thousands of square degrees without any source preselection other than the photometric depth in the detection band, and thus single-epoch photometry has the potential to provide details on the physical properties of quasar populations that do not satisfy the preselection criteria of previous spectroscopic surveys.