BASS. XXIV. The BASS DR2 Spectroscopic Line Measurements and AGN Demographics

Creators: Oh, Kyuseok; Koss, Michael J.; Ueda, Yoshihiro; Stern, Daniel; Ricci, Claudio; Trakhtenbrot, Benny; Powell, Meredith C.; den Brok, Jakob S.; Lamperti, Isabella; Mushotzky, Richard; Ricci, Federica; Bär, Rudolf E.; Rojas, Alejandra F.; Ichikawa, Kohei; Riffel, Rogério; Treister, Ezequiel; Harrison, Fiona; Urry, C. Megan; Bauer, Franz E.; Schawinski, Kevin

Abstract

We present the second catalog and data release of optical spectral line measurements and active galactic nucleus (AGN) demographics of the BAT AGN Spectroscopic Survey, which focuses on the Swift-BAT hard X-ray detected AGNs. We use spectra from dedicated campaigns and publicly available archives to investigate spectral properties of most of the AGNs listed in the 70 month Swift-BAT all-sky catalog; specifically, 743 of the 746 unbeamed and unlensed AGNs (99.6%). We find a good correspondence between the optical emission line widths and the hydrogen column density distributions using the X-ray spectra, with a clear dichotomy of AGN types for N_H = 10²² cm⁻². Based on optical emission-line diagnostics, we show that 48%–75% of BAT AGNs are classified as Seyfert, depending on the choice of emission lines used in the diagnostics. The fraction of objects with upper limits on line emission varies from 6% to 20%. Roughly 4% of the BAT AGNs have lines too weak to be placed on the most commonly used diagnostic diagram, [O iii]λ5007/Hβ versus [N ii]λ6584/Hα, despite the high signal-to-noise ratio of their spectra. This value increases to 35% in the [O iii]λ5007/[O ii]λ3727 diagram, owing to difficulties in line detection. Compared to optically selected narrow-line AGNs in the Sloan Digital Sky Survey, the BAT narrow-line AGNs have a higher rate of reddening/extinction, with Hα/Hβ > 5 (∼36%), indicating that hard X-ray selection more effectively detects obscured AGNs from the underlying AGN population. Finally, we present a subpopulation of AGNs that feature complex broad lines (34%, 250/743) or double-peaked narrow emission lines (2%, 17/743).

Additional Information

© 2022. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. Received 2021 December 16; revised 2022 February 16; accepted 2022 February 17; published 2022 July 15. The BAT AGN Spectroscopic Survey Data Release 2. We are grateful to the anonymous referee for a number of clarifications that improved the quality of the manuscript. K.O. acknowledges support from the National Research Foundation of Korea (NRF-2020R1C1C1005462). This research was supported in part by the Japan Society for the Promotion of Science (JSPS) postdoctoral fellowship program for research in Japan (ID: P17321). We acknowledge support from NASA through ADAP award NNH16CT03C (M.K.); the JSPS KAKENHI grant No. 20H01946 (Y.U.); the Fondecyt Iniciacion grant 11190831 (C.R.); the Israel Science Foundation (grant No. 1849/19, B.T.); the Comunidad de Madrid through the Atracción de Talento Investigador Grant 2018-T1/TIC-11035 (I.L.); FONDECYT Postdoctorado project No. 3210157 (A.R.L.). R.R. thanks to Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq, Proj. 311223/2020-6, 304927/2017-1 and 400352/2016-8), Fundação de amparo à pesquisa do Rio Grande do Sul (FAPERGS, Proj. 16/2551-0000251-7 and 19/1750-2), Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES, Proj. 0001). We acknowledge support from FONDECYT Regular 1190818 (E.T., F.E.B.) and 1200495 (F.E.B., E.T.), ANID grants CATA-Basal AFB-170002 and FB210003 (E.T., F.E.B.), Anillo ACT172033 (E.T.), Millennium Nucleus NCN19_058 (TITANs; E.T.) and Millennium Science Initiative Program 2013 ICN12_009 (MAS; F.E.B.). C.M.U. acknowledges support from the National Science Foundation under grant No. AST-1715512. Some of the optical spectra were taken with Doublespec at Palomar via Yale (PI M. Powell, 2017-2019, 16 nights) as well as Caltech (PI F. Harrison) and JPL (PI D. Stern) from programs from 2013–2020. This work made use of observations collected at the European Southern Observatory under ESO programs 98.A-0635, 99-A-0403, 100.B-0672, 101.A-0765, 102.A-0433, 103.A-0521, and 104.A-0353. Based on observations from seven CNTAC programs: CN2016A-80, CN2018A-104, CN2018B-83, CN2019A-70, CN2019B-77, CN2020A-90, and CN2020B-48 (PI C. Ricci). Based on observations obtained at the Southern Astrophysical Research (SOAR) telescope, which is a joint project of the Ministério da Ciência, Tecnologia e Inovações (MCTI/LNA) do Brasil, the US National Science Foundations NOIRLab, the University of North Carolina at Chapel Hill (UNC), and Michigan State University (MSU). Based on observations at Kitt Peak National Observatory at NSFs NOIRLab (NOIRLab Prop. ID 52, 2946; PI: F. Bauer), which is managed by the Association of Universities for Research in Astronomy (AURA) under a cooperative agreement with the National Science Foundation. Some of the data presented herein were obtained at the W.M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W.M. Keck Foundation. The authors wish to recognize and acknowledge the very significant cultural role and reverence that the summit of Maunakea has always had within the indigenous Hawaiian community. We are most fortunate to have the opportunity to conduct observations from this mountain. This research has made use of NASA's ADS Service. This research has made use of the NASA/ IPAC Infrared Science Archive, which is operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration. Funding for SDSS-III has been provided by the Alfred P. Sloan Foundation, the Participating Institutions, the National Science Foundation, and the U.S. Department of Energy Office of Science. The SDSS-III website is http://www.sdss3.org/. SDSS-III is managed by the Astrophysical Research Consortium for the Participating Institutions of the SDSS-III Collaboration including the University of Arizona, the Brazilian Participation Group, Brookhaven National Laboratory, Carnegie Mellon University, University of Florida, the French Participation Group, the German Participation Group, Harvard University, the Instituto de Astrofisica de Canarias, the Michigan State/Notre Dame/JINA Participation Group, Johns Hopkins University, Lawrence Berkeley National Laboratory, Max Planck Institute for Astrophysics, Max Planck Institute for Extraterrestrial Physics, New Mexico State University, New York University, Ohio State University, Pennsylvania State University, University of Portsmouth, Princeton University, the Spanish Participation Group, University of Tokyo, University of Utah, Vanderbilt University, University of Virginia, University of Washington, and Yale University. The Digitized Sky Surveys were produced at the Space Telescope Science Institute under U.S. Government grant NAG W-2166. The images of these surveys are based on photographic data obtained using the Oschin Schmidt Telescope on Palomar Mountain and the UK Schmidt Telescope. The plates were processed into the present compressed digital form with the permission of these institutions. The National Geographic Society—Palomar Observatory Sky Atlas (POSS-I) was made by the California Institute of Technology with grants from the National Geographic Society. The Second Palomar Observatory Sky Survey (POSS-II) was made by the California Institute of Technology with funds from the National Science Foundation, the National Geographic Society, the Sloan Foundation, the Samuel Oschin Foundation, and the Eastman Kodak Corporation. The Oschin Schmidt Telescope is operated by the California Institute of Technology and Palomar Observatory. The UK Schmidt Telescope was operated by the Royal Observatory Edinburgh, with funding from the UK Science and Engineering Research Council (later the UK Particle Physics and Astronomy Research Council), until 1988 June, and thereafter by the Anglo-Australian Observatory. The blue plates of the southern Sky Atlas and its Equatorial Extension (together known as the SERC-J), as well as the Equatorial Red (ER), and the Second Epoch [red] Survey (SES) were all taken with the UK Schmidt. Facilities: Du Pont (Boller and Chivens spectrograph) - , Hale (Doublespec) - , Keck:I (LRIS) - , SOAR (Goodman) - , Swift(BAT) - , VLT:Kueyen (X-Shooter) - . Software: gandalf (Sarzi et al. 2006), ESO Reflex (Freudling et al. 2013).

Attached Files

Published - Oh_2022_ApJS_261_4.pdf

Accepted Version - 2203.00017.pdf

Files

2203.00017.pdf

Files (4.7 MB)

Name	Size	Download all
2203.00017.pdf md5:48e3bc38ee569ea2337d950d83f7ff40	2.3 MB	Preview Download
Oh_2022_ApJS_261_4.pdf md5:e1892815f9e7f2b10a3f71d51e013daf	2.4 MB	Preview Download

Additional details

	All versions	This version
Views	0	0
Downloads	0	0
Data volume	0 Bytes	0 Bytes