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arXiv · 2207.12428

BAT AGN Spectroscopic Survey XXI: The Data Release 2 Overview

Michael J. Koss·Benny Trakhtenbrot·Claudio Ricci·Franz E. Bauer·Ezequiel Treister·Richard Mushotzky·C. Megan Urry·Tonima T. Ananna·Mislav Balokovic·Jakob S. den Brok·S. Bradley Cenko·Fiona Harrison·Kohei Ichikawa·Isabella Lamperti·Amy Lein·Julian E. Mejia-Restrepo·Kyuseok Oh·Fabio Pacucci·Ryan W. Pfeifle·Meredith C. Powell·George C. Privon·Federica Ricci·Mara Salvato·Kevin Schawinski·Taro Shimizu·Krista L. Smith·Daniel Stern
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Abstract

The BAT AGN Spectroscopic Survey (BASS) is designed to provide a highly complete census of the key physical parameters of supermassive black holes (SMBHs) that power local active galactic nuclei (AGN) (z<0.3), including their bolometric luminosity, black hole mass, accretion rates, and line-of-sight gas obscuration, and the distinctive properties of their host galaxies (e.g., star formation rates, masses, and gas fractions). We present an overview of the BASS data release 2 (DR2), an unprecedented spectroscopic survey in spectral range, resolution, and sensitivity, including 1449 optical (3200-10000 A) and 233 NIR (1-2.5 um) spectra for the brightest 858 ultra-hard X-ray (14-195 keV) selected AGN across the entire sky and essentially all levels of obscuration. This release provides a highly complete set of key measurements (emission line measurements and central velocity dispersions), with 99.9% measured redshifts and 98% black hole masses estimated (for unbeamed AGN outside the Galactic plane). The BASS DR2 AGN sample represents a unique census of nearby powerful AGN, spanning over 5 orders of magnitude in AGN bolometric luminosity, black hole mass, Eddington ratio, and obscuration. The public BASS DR2 sample and measurements can thus be used to answer fundamental questions about SMBH growth and its links to host galaxy evolution and feedback in the local universe, as well as open questions concerning SMBH physics. Here we provide a brief overview of the survey strategy, the key BASS DR2 measurements, data sets and catalogs, and scientific highlights from a series of DR2-based works.

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Michael J. Koss, Benny Trakhtenbrot, Claudio Ricci, Franz E. Bauer, Ezequiel Treister, Richard Mushotzky, C. Megan Urry, Tonima T. Ananna, Mislav Balokovic, Jakob S. den Brok, S. Bradley Cenko, Fiona Harrison, Kohei Ichikawa, Isabella Lamperti, Amy Lein, Julian E. Mejia-Restrepo, Kyuseok Oh, Fabio Pacucci, Ryan W. Pfeifle, Meredith C. Powell, George C. Privon, Federica Ricci, Mara Salvato, Kevin Schawinski, Taro Shimizu, Krista L. Smith, Daniel Stern. 2022-07-25. BAT AGN Spectroscopic Survey XXI: The Data Release 2 Overview. https://doi.org/10.3847/1538-4365%2Fac6c8f

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