BAT AGN Spectroscopic Survey. I. Spectral Measurements, Derived Quantities, and AGN Demographics

By M. Koss, B. Trakhtenbrot, C. Ricci, I. Lamperti, K. Oh, S. Berney, Kevin Schawinski, M. Baloković, L. Baronchelli, D. Crenshaw and 14 more. 2017

224 citations recorded by the source corpus.

We present the first catalog and data release of the Swift-BAT AGN Spectroscopic Survey. We analyze optical spectra of the majority of the detected AGNs (77%, 642/836)based on their 14–195 keV emission in the 70-month Swift-BAT all-sky catalog. This includes redshift determination, absorption and emission-line measurements, and black hole mass and accretion rate estimates for the majority of obscured and unobscured AGNs (74%, 473/642), with 340 measured for the first time. With ∼90% of sources at , the survey represents a significant advance in the census of hard X-ray-selected AGNs in the local universe. In this first catalog paper, we describe the spectroscopic observations and data sets, and our initial spectral analysis. The FWHMs of the emission lines show broad agreement with the X-ray obscuration (∼94%), such that Sy 1–1.8 have cm−2, and Seyfert 2 have cm−2. Seyfert 1.9, however, show a range of column densities. Compared to narrow-line AGNs in the SDSS, the X-ray-selected AGNs have a larger fraction of dusty host galaxies ( ), suggesting that these types of AGN are missed in optical surveys. Using the [O iii] λ5007/Hβ and [N ii] λ6583/Hα emission-line diagnostic, about half of the sources are classified as Seyferts; ∼15% reside in dusty galaxies that lack an Hβ detection, but for which the upper limits on line emission imply either a Seyfert or LINER, are in galaxies with weak or no emission lines despite high-quality spectra, and a few percent each are LINERS, composite galaxies, H ii regions, or in known beamed AGNs.

Subfields: Astronomy and Astrophysics, Instrumentation, Nuclear and High Energy Physics

View Paper: https://www.semanticscholar.org/paper/57d2997a16d18bfe819a326644dba694646c54cd

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The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Astronomy and Astrophysics

1. D. M. Alexander
2. R. Hickox
3. E. Treister
4. Kevin Schawinski
5. F. E. Bauer
6. Y. Ueda
7. W. N. Brandt
8. N. Gehrels

In Instrumentation

1. D. M. Alexander
2. R. Hickox
3. Kevin Schawinski
4. Y. Ueda
5. C. Ricci
6. E. Treister
7. S. Cenko
8. B. Trakhtenbrot

In Nuclear and High Energy Physics

1. D. M. Alexander
2. R. Hickox
3. E. Treister
4. R. Mushotzky
5. Kevin Schawinski
6. C. Ricci
7. F. E. Bauer
8. Poshak Gandhi

Citations in the corpus

• The 105-Month Swift-BAT All-sky Hard X-Ray Survey (2018, background): “…edition of quasars and AGN catalogues (Véron-Cetty & Véron 201020) as well as recent investigation from the Swift -BAT AGN Spectroscopic Survey (Koss et al. 2017; Ricci et al. 2017a) and INTEGRAL mission based X-ray catalogues (INTEGRAL General Reference catalog21, INTEGRAL IBIS/ISGRI…”
• BAT AGN Spectroscopic Survey. V. X-Ray Properties of the Swift/BAT 70-month AGN Catalog (2017, methodology): “A large effort has been made to collect optical spectroscopy for most of the sources reported in the 70-month Swift/BAT catalog, which allowed to infer black hole masses for both obscured and unobscured objects (Koss et al. 2017).”
• Obscured Active Galactic Nuclei (2018, background): “…the optical spectral types of AGN if NH = 10 22 cm−2 is taken as the threshold between Xray absorbed and X-ray unabsorbed AGN (≈ 80–90% agreement in the X-ray and optical obscuration signatures; e.g., Malizia et al. 2012; Merloni et al. 2014; Burtscher et al. 2016; Koss et al. 2017); see Figure 7.”