Browsing by Author "Harrison, Fiona"

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    An Iwasawa-Taniguchi effect for Compton-thick active galactic nuclei
    (2018) Boorman, Peter G.; Gandhi, Poshak; Balokovic, Mislav; Brightman, Murray; Harrison, Fiona; Ricci, Claudio; Stern, Daniel
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    BASS XLIV. Morphological preferences of local hard X-ray selected AGNs
    (EDP Sciences, 2025) Parra Tello, Miguel Agustín; Bauer, Franz E.; Cicco, Demetra de; Doll, Goran; Koss, Michael; Treister, Ezequiel; Finlez, Carolina; Troncoso Balbiano, Marco Javier; Auge, Connor; Moral Castro, Ignacio del; Chung, Aeree; Gupta, Kriti K.; Kim, Jeein; Oh, Kyuseok; Ricci, Claudio; Ricci, Federica; Rojas, Alejandra; Caglar, Turgay; Harrison, Fiona; Powell, Meredith C.; Stern, Daniel; Trakhtenbrot, Benny; Urry, C. Megan
    We present detailed morphological classifications for the hosts of 1189 hard X-ray selected (14–195 keV) active galactic nuclei (AGNs) from the Swift-BAT 105-month catalog as part of the BAT AGN Spectroscopic Survey (BASS). BASS provides a powerful all-sky census of nearby AGNs, minimizing obscuration biases and providing a robust dataset for studying AGN-host galaxy connections. Classifications are based on a volunteer-based visual inspection workflow on the Zooniverse platform, adapted from the Galaxy Zoo DECaLS (GZD) project. Dual-contrast grz color composite images, generated from public surveys (e.g., NOAO Legacy Survey, Pan-STARRS, SDSS) and dedicated observations enabled key morphological features to be identified. Our analysis reveals that, with respect to a control sample of inactive galaxies, BASS AGN hosts show a deficiency of smooth elliptical galaxies (∼70%) and spiral galaxies with prominent arms (∼80%), while displaying an excess of mergers or disturbed systems (∼400%), and disk galaxies without a spiral structure (∼300%). These trends are found after controlling for redshift and i-band magnitude, which suggests a preference for AGN activity in gas-rich, dynamically disturbed environments or transitional disk systems. We also find a higher bar fraction among AGN hosts than in a control sample (∼50% vs. ∼30%). We further explore the relationships between AGN properties (e.g., X-ray luminosity, black hole mass, and Eddington ratio) and host morphology, and find that high-luminosity and high-accretion AGNs preferentially reside in smooth or point-like hosts. At the same time, lower-luminosity AGNs are more common in disk galaxies. These results underscore the importance of morphological studies in understanding the fueling and feedback mechanisms that drive AGN activity and their role in galaxy evolution. Our dataset provides a valuable benchmark for future multiwavelength surveys (e.g. LSST, Roman, and Euclid) and automated morphological classification efforts.
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    BASS XXXII: Studying the Nuclear Millimeter-wave Continuum Emission of AGNs with ALMA at Scales ≲100-200 pc
    (2022) Kawamuro, Taiki; Ricci, Claudio; Imanishi, Masatoshi; Mushotzky, Richard F.; Izumi, Takuma; Ricci, Federica; Bauer, Franz E.; Koss, Michael J.; Trakhtenbrot, Benny; Ichikawa, Kohei; Rojas, Alejandra F.; Smith, Krista Lynne; Shimizu, Taro; Oh, Kyuseok; den Brok, Jakob S.; Baba, Shunsuke; Balokovic, Mislay; Chang, Chin-Shin; Kakkad, Darshan; Pfeifle, Ryan W.; Privon, George C.; Temple, Matthew J.; Ueda, Yoshihiro; Harrison, Fiona; Powell, Meredith C.; Stern, Daniel; Urry, Meg; Sanders, David B.
    To understand the origin of nuclear (less than or similar to 100 pc) millimeter-wave (mm-wave) continuum emission in active galactic nuclei (AGNs), we systematically analyzed subarcsecond resolution Band-6 (211-275 GHz) Atacama Large Millimeter/submillimeter Array data of 98 nearby AGNs (z < 0.05) from the 70 month Swift/BAT catalog. The sample, almost unbiased for obscured systems, provides the largest number of AGNs to date with high mm-wave spatial resolution sampling (similar to 1-200 pc), and spans broad ranges of 14-150 keV luminosity {40< log [L-14(-150)/(erg s(-1))] < 45}, black hole mass [5 < log(M-BH/M-circle dot) < 10], and Eddington ratio (-4 < log lambda(Edd) < 2). We find a significant correlation between 1.3 mm (230 GHz) and 14-150 keV luminosities. Its scatter is approximate to 0.36 dex, and the mm-wave emission may serve as a good proxy of the AGN luminosity, free of dust extinction up to N-H similar to 10(26) CM-2. While the mm-wave emission could be self-absorbed synchrotron radiation around the X-ray corona according to past works, we also discuss different possible origins of the mm-wave emission: AGN-related dust emission, outflow-driven shocks, and a small-scale (<200 pc) jet. The dust emission is unlikely to be dominant, as the mm-wave slope is generally flatter than expected. Also, due to no increase in the mm-wave luminosity with the Eddington ratio, a radiation-driven outflow model is possibly not the common mechanism Furthermore, we find independence of the mm-wave luminosity on indicators of the inclination angle from the polar axis of the nuclear structure, which is inconsistent with a jet model whose luminosity depends only on the angle.
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    BASS XXXIX: Swift-BAT AGN with changing-look optical spectra
    (2023) Temple, Matthew J.; Ricci, Claudio; Koss, Michael J.; Trakhtenbrot, Benny; Bauer, Franz E.; Mushotzky, Richard; Rojas, Alejandra F.; Caglar, Turgay; Harrison, Fiona; Oh, Kyuseok; Gonzalez, Estefania Padilla; Powell, Meredith C.; Ricci, Federica; Riffel, Rogerio; Stern, Daniel; Urry, C. Megan
    Changing-look (CL) AGN are unique probes of accretion onto supermassive black holes (SMBHs), especially when simultaneous observations in complementary wavebands allow investigations into the properties of their accretion flows. We present the results of a search for CL behaviour in 412 Swift-BAT detected AGN with multiple epochs of optical spectroscopy from the BAT AGN Spectroscopic Survey (BASS). 125 of these AGN also have 14-195 keV ultra-hard X-ray light curves from Swift-BAT which are contemporaneous with the epochs of optical spectroscopy. Eight CL events are presented for the first time, where the appearance or disappearance of broad Balmer line emission leads to a change in the observed Seyfert type classification. Combining with known events from the literature, 21 AGN from BASS are now known to display CL behaviour. Nine CL events have 14-195 keV data available, and five of these CL events can be associated with significant changes in their 14-195 keV flux from BAT. The ultra-hard X-ray flux is less affected by obscuration and so these changes in the 14-195 keV band suggest that the majority of our CL events are not due to changes in line-of-sight obscuration. We derive a CL rate of 0.7-6.2 per cent on 10-25 yr time-scales, and show that many transitions happen within at most a few years. Our results motivate further multiwavelength observations with higher cadence to better understand the variability physics of accretion onto SMBHs.
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    BASS-XL: X-ray variability properties of unobscured active galactic nuclei
    (2023) Tortosa, Alessia; Ricci, Claudio; Arevalo, Patricia; Koss, Michael J.; Bauer, Franz E.; Trakhtenbrot, Benny; Mushotzky, Richard; Temple, Matthew J.; Ricci, Federica; Lilayu, Alejandra Rojas; Kawamuro, Taiki; Caglar, Turgay; Liu, Tingting; Harrison, Fiona; Oh, Kyuseok; Powell, Meredith Clark; Stern, Daniel; Urry, Claudia Megan
    We investigate the X-ray variability properties of Seyfert 1 Galaxies belonging to the BAT AGN Spectroscopic Survey (BASS). The sample includes 151 unobscured (N-H < 10(22) cm(-2)) AGNs observed with XMM-Newton for a total exposure time of similar to 27 ms, representing the deepest variability study done so far with high signal-to-noise XMM-Newton observations, almost doubling the number of observations analysed in previous works. We constrain the relation between the normalized excess variance and the 2-10 keV AGN luminosities, black hole masses, and Eddington ratios. We find a highly significant correlation between sigma(2)(NXS) and M-BH, with a scatter of similar to 0.85 dex. For sources with high L2-10 this correlation has a lower normalization, confirming that more luminous (higher mass) AGNs show less variability. We explored the sigma(2)(NXS) versus M-BH relation for the sub-sample of sources with M-BH estimated via the 'reverberation mapping' technique, finding a tighter anticorrelation, with a scatter of similar to 0.65 dex. We examine how the sigma(2)(NXS) changes with energy by studying the relation between the variability in the hard (3-10 keV) and the soft (0.2-1 keV)/medium (1-3 keV) energy bands, finding that the spectral components dominating the hard energy band are more variable than the spectral components dominating in softer energy bands, on time-scales shorter than 10 ks.
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    BASS. LIII. The Eddington Ratio as the Primary Regulator of the Fraction of X-Ray Emission in Active Galactic Nuclei
    (2025) Gupta, Kriti Kamal; Ricci, Claudio; Tortosa, Alessia; Temple, Matthew J.; Koss, Michael J.; Trakhtenbrot, Benny; Bauer, Franz E.; Treister, Ezequiel; Mushotzky, Richard; Kammoun, Elias; Papadakis, Iossif; Oh, Kyuseok; Rojas, Alejandra; Chang, Chin-Shin; Diaz, Yaherlyn; Jana, Arghajit; Kakkad, Darshan; Moral Castro, Ignacio del; Peca, Alessandro; Powell, Meredith C.; Stern, Daniel; Urry, C. Megan; Harrison, Fiona
    Active galactic nuclei (AGN) emit radiation via accretion across the entire energy spectrum. While the standard disk and corona model can somewhat describe this emission, it fails to predict specific features such as the soft X-ray excess, the short-term optical/UV variability, and the observed UV/X-ray correlation in AGN. In this context, the fraction of AGN emission in different bands (i.e., bolometric corrections) can be useful to better understand the accretion physics of AGN. Past studies have shown that the X-ray bolometric corrections are strongly dependent on the physical properties of AGN, such as their luminosities and Eddington ratios. However, since these two parameters depend on each other, it has been unclear which is the main driver of the X-ray bolometric corrections. We present here results from a large study of hard-X-ray-selected (14–195 keV) nearby (z < 0.1) AGN. Based on our systematic analysis of the simultaneous optical-to-X-ray spectral energy distributions of 236 unobscured AGN, we found that the primary parameter controlling the X-ray bolometric corrections is the Eddington ratio. Our results show that, while the X-ray bolometric correction increases with the bolometric luminosity for sources with intermediate Eddington ratios (0.01–1), this dependence vanishes for sources with lower Eddington ratios (<0.01). This could be used as evidence for a change in the accretion physics of AGN at low Eddington ratios.
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    BASS. XLIX. Characterization of Highly Luminous and Obscured AGNs: Local X-Ray and [Ne V]λ3426 Emission in Comparison with the High-redshift Universe
    (2025) Peca, Alessandro; Koss, Michael J.; Oh, Kyuseok; Ricci, Claudio; Trakhtenbrot, Benny; Mushotzky, Richard; Treister, Ezequiel; Urry, C. Megan; Pizzetti, Andrealuna; Ichikawa, Kohei; Tortosa, Alessia; Ricci, Federica; Signorini, Matilde; Kakkad, Darshan; Chang, Chin-Shin; Mazzolari, Giovanni; Caglar, Turgay; Magno, Macon; Moral Castro, Ignacio del; Boorman, Peter G.; Ananna, Tonima T.; Harrison, Fiona; Stern, Daniel; Sanders, David
    We present a detailed analysis of the most luminous and obscured active galactic nuclei (AGNs) detected in the ultra-hard X-ray band (14–195 kev) by the Swift/Burst Alert Telescope. Our sample comprises 21 X-ray luminous (log LX/erg s > 44.6 1 , 2–10 keV) AGNs at z < 0.6, optically classified as Seyfert 1.9 and 2. Using NuSTAR, XMM-Newton, Suzaku, and Chandra data, we constrain AGN properties such as absorption column density NH, photon index Γ, intrinsic LX, covering factor, and iron Kα equivalent width. We find median line-ofsight / = + logNH cm 23.5 2 1.2 0.5 and 2–10 keV rest-frame, de-absorbed / = + log LX erg s 44.7 1 0.6 0.8, at the 5th and 95th percentiles. For sources with black hole mass estimates (12/20), we find a weak correlation between Γ and Eddington ratio (λEdd). Of these, six (50% ± 13%) lie in the NH-λEdd “forbidden region” and exhibit a combined higher prevalence of NH variability and outflow signatures, suggesting a transitional phase where AGN feedback may be clearing the obscuring material. For the 13/21 sources with multi-epoch X-ray spectroscopy, + 85 1 5 5% exhibit variability in either 2–10 keV flux (+ 77 1 8 5%) or line-of-sight NH (+ 33 1 1 0 5% ). For the 20/21 sources with available near-UV/optical spectroscopy, we detect [Ne v]λ3426 in 17 (+ 85 11 5 %), confirming its reliability to probe AGN emission even in heavily obscured systems. When renormalized to the same [O III]λ5007 peak flux as z = 2 −9 narrow-line AGNs identified with JWST, our sample exhibits significantly stronger [Ne v]λ3426 emission, suggesting that high-redshift obscured AGNs may be intrinsically weaker in [Ne v]λ3426 or that [Ne v]λ3426 is more challenging to detect in those environments. The sources presented in this work serve as a benchmark for high-redshift analogs, showing the potential of [Ne v]λ3426 to reveal obscured AGNs and the need for future missions to expand X-ray studies into the high-redshift Universe.
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    BASS. XXI. The Data Release 2 Overview
    (2022) Koss, Michael J.; Trakhtenbrot, Benny ; Ricci, Claudio ; Bauer, Franz Erik; Treister, Ezequiel ; Mushotzky, Richard ; Urry, C. Megan ; Ananna, Tonima T. ; Baloković, Mislav ; den Brok, Jakob S. ; Cenko, S. Bradley ; Harrison, Fiona ; Ichikawa, Kohei ; Lamperti, Isabella; Lein, Amy ; Mejía-Restrepo, Julian E. ; Oh, Kyuseok ; Pacucci, Fabio ; Pfeifle, Ryan W. ; Powell, Meredith C. ; Privon, George C. ; Ricci, Federica; Salvato, Mara ; Schawinski, Kevin ; Shimizu, Taro ; Krista L. Smith; Stern, Daniel
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    BASS. XXII. The BASS DR2 AGN Catalog and Data
    (2022) Koss, Michael J. ; Ricci, Claudio ; Trakhtenbrot, Benny ; Oh, Kyuseok ; den Brok, Jakob S. ; Mejía-Restrepo, Julian E. ; Stern, Daniel ; Privon, George C. ; Treister, Ezequiel ; Powell, Meredith C.; Mushotzky, Richard ; Bauer, Franz Erik; Ananna, Tonima T. ; Baloković, Mislav ; Bär, Rudolf ; Becker, George ; Bessiere, Patricia ; Burtscher, Leonard ; Caglar, Turgay ; Congiu, Enrico ; Evans, Phil ; Harrison, Fiona ; Heida, Marianne ; Ichikawa, Kohei ; Kamraj, Nikita; Lamperti, Isabella; Pacucci, Fabio ; Ricci, Federica ; Riffel, Rogério; Rojas, Alejandra F. ; Schawinski, Kevin ; Temple, Matthew J. ; Urry, C. Megan ; Veilleux, Sylvain ; Williams, Jonathan
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    BASS. XXIII. A New Mid-infrared Diagnostic for Absorption in Active Galactic Nuclei
    (2022) Pfeifle, Ryan W.; Ricci, Claudio; Boorman, Peter G.; Stalevski, Marko; Asmus, Daniel; Trakhtenbrot, Benny; Koss, Michael J.; Stern, Daniel; Ricci, Federica; Satyapal, Shobita; Ichikawa, Kohei; Rosario, David J.; Caglar, Turgay; Treister, Ezequiel; Powell, Meredith; Oh, Kyuseok; Urry, C. Megan; Harrison, Fiona
    In this study, we use the Swift/BAT AGN sample, which has received extensive multiwavelength follow-up analysis as a result of the BAT AGN Spectroscopic Survey, to develop a diagnostic for nuclear obscuration by examining the relationship between the line-of-sight column densities (N-H), the 2-10 keV to 12 mu m luminosity ratio, and WISE mid-infrared colors. We demonstrate that heavily obscured AGNs tend to exhibit both preferentially "redder" mid-infrared colors and lower values of L-X,L-Obs./L-12 mu m than less obscured AGNs, and we derive expressions relating N-H to the L-X,L-Obs./L-12 mu m and L-22 mu m/L-4.6 mu m luminosity ratios, as well as develop diagnostic criteria using these ratios. Our diagnostic regions yield samples that are greater than or similar to 80% complete and greater than or similar to 60% pure for AGNs with log(N-H/cm(-2)) >= 24, as well as greater than or similar to 85% pure for AGNs with log(N-H/cm(-2)) greater than or similar to 23.5. We find that these diagnostics cannot be used to differentiate between optically star-forming galaxies and active galaxies. Further, mid-IR contributions from host galaxies that dominate the observed 12 mu m emission can lead to larger apparent X-ray deficits and redder mid-IR colors than the AGNs would intrinsically exhibit, though this effect helps to better separate less and more obscured AGNs. Finally, we test our diagnostics on two catalogs of AGNs and infrared galaxies, including the XMM-Newton XXL-N field, and we identify several known Compton-thick AGNs, as well as a handful of candidate heavily obscured AGNs based upon our proposed obscuration diagnostics.
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    BASS. XXIV. The BASS DR2 Spectroscopic Line Measurements and AGN Demographics
    (2022) 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; Bar, Rudolf E.; Rojas, Alejandra F.; Ichikawa, Kohei; Riffel, Rogerio; Treister, Ezequiel; Harrison, Fiona; Urry, C. Megan; Bauer, Franz E.; Schawinski, Kevin
    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) = 10(22) 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]lambda 5007/H beta versus [N ii]lambda 6584/H alpha, despite the high signal-to-noise ratio of their spectra. This value increases to 35% in the [O iii]lambda 5007/[O ii]lambda 3727 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 H alpha/H beta > 5 (similar to 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).
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    BASS. XXIX. The Near-infrared View of the Broad-line Region (BLR): The Effects of Obscuration in BLR Characterization
    (2022) Ricci, Federica ; Treister, Ezequiel ; Bauer, Franz E.; Mejía-Restrepo, Julian E. ; Koss, Michael J. ; den Brok, Jakob S. ; Baloković, Mislav ; Bär, Rudolf ; Bessiere, Patricia ; Caglar, Turgay ; Harrison, Fiona ; Ichikawa, Kohei ; Kakkad, Darshan; Lamperti, Isabella ; Mushotzky, Richard ; Oh, Kyuseok ; Powell, Meredith C. ; Privon, George C. ; Ricci, Claudio ; Riffel, Rogerio ; Rojas, Alejandra F. ; Sani, Eleonora ; Smith, Krista L. ; Stern, Daniel ; Trakhtenbrot, Benny ; Urry, C. Megan ; Veilleux, Sylvain
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    BASS. XXVI. DR2 Host Galaxy Stellar Velocity Dispersions
    (2022) Koss, Michael J.; Trakhtenbrot, Benny; Ricci, Claudio; Oh, Kyuseok; Bauer, Franz E.; Stern, Daniel; Caglar, Turgay; den Brok, Jakob S.; Mushotzky, Richard; Ricci, Federica; Mejia-Restrepo, Julian E.; Lamperti, Isabella; Treister, Ezequiel; Baer, Rudolf E.; Harrison, Fiona; Powell, Meredith C.; Privon, George C.; Riffel, Rogerio; Rojas, Alejandra F.; Schawinski, Kevin; Urry, C. Megan
    We present new central stellar velocity dispersions for 484 Sy 1.9 and Sy 2 from the second data release of the Swift/BAT AGN Spectroscopic Survey (BASS DR2). This constitutes the largest study of velocity dispersion measurements in X-ray-selected obscured active galactic nuclei (AGN) with 956 independent measurements of the Ca ii H and K lambda 3969, 3934 and Mg I lambda 5175 region (3880-5550 angstrom) and the calcium triplet region (8350-8730 angstrom) from 642 spectra mainly from VLT/X-Shooter or Palomar/DoubleSpec. Our sample spans velocity dispersions of 40-360 km s(1), corresponding to 4-5 orders of magnitude in black hole mass (M (BH) = 10(5.5-9.6) M (circle dot)), bolometric luminosity (L (bol) similar to 10(42-46) erg s(-1)), and Eddington ratio (L/L (Edd) similar to 10(-5) to 2). For 281 AGN, our data and analysis provide the first published central velocity dispersions, including six AGN with low-mass black holes (M (BH) = 10(5.5-6.5) M (circle dot)), discovered thanks to high spectral resolution observations (sigma (inst) similar to 25 km s(-1)). The survey represents a significant advance with a nearly complete census of velocity dispersions of hard X-ray-selected obscured AGN with measurements for 99% of nearby AGN (z < 0.1) outside the Galactic plane ( divide b divide > 10 degrees). The BASS AGN have much higher velocity dispersions than the more numerous optically selected narrow-line AGN (i.e., similar to 150 versus similar to 100 km s(-1)) but are not biased toward the highest velocity dispersions of massive ellipticals (i.e., >250 km s(-1)). Despite sufficient spectral resolution to resolve the velocity dispersions associated with the bulges of small black holes (similar to 10(4-5) M (circle dot)), we do not find a significant population of super-Eddington AGN. Using estimates of the black hole sphere of influence from velocity dispersion, direct stellar and gas black hole mass measurements could be obtained with existing facilities for more than similar to 100 BASS AGN.
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    BASS. XXVIII. Near-infrared Data Release 2: High-ionization and Broad Lines in Active Galactic Nuclei
    (2022) den Brok, Jakob S.; Koss, Michael J.; Trakhtenbrot, Benny; Stern, Daniel; Cantalupo, Sebastiano; Lamperti, Isabella; Ricci, Federica; Ricci, Claudio; Oh, Kyuseok; Bauer, Franz E.; Riffel, Rogerio; Rodriguez-Ardila, Alberto; Baer, Rudolf; Harrison, Fiona; Ichikawa, Kohei; Mejia-Restrepo, Julian E.; Mushotzky, Richard; Powell, Meredith C.; Boissay-Malaquin, Rozenn; Stalevski, Marko; Treister, Ezequiel; Urry, C. Megan; Veilleux, Sylvain
    We present the BAT AGN Spectroscopic Survey (BASS) Near-infrared Data Release 2 (DR2), a study of 168 nearby ((z) over bar = 0.04, z < 0.6) active galactic nuclei (AGN) from the all-sky Swift Burst Array Telescope X-ray survey observed with the Very Large Telescope (VLT)/X-shooter in the near-infrared (NIR; 0.8-2.4 mu m). We find that 49/109 (45%) Seyfert 2 and 35/58 (60%) Seyfert 1 galaxies observed with VLT/X-shooter show at least one NIR high-ionization coronal line (CL; ionization potential chi > 100 eV). Comparing the emission of the [Si VI] lambda 1.9640 CL with the X-ray emission for the DR2 AGN, we find a significantly tighter correlation, with a lower scatter (0.37 dex) than that for the optical [O III] lambda 5007 line (0.71 dex). We do not find any correlation between CL emission and the X-ray photon index Gamma. We find a clear trend of line blueshifts with increasing ionization potential in several CLs, such as [Si VI] lambda 1.9640, [Si X] lambda 1.4300, [S VIII] lambda 0.9915, and [S IX] lambda 1.2520, indicating the radial structure of the CL region. Finally, we find a strong underestimation bias in black hole mass measurements of Sy 1.9 using broad H alpha due to the presence of significant dust obscuration. In contrast, the broad Pa alpha and Pa beta emission lines are in agreement with the M-sigma relation. Based on the combined DR1 and DR2 X-shooter sample, the NIR BASS sample now comprises 266 AGN with rest-frame NIR spectroscopic observations, the largest set assembled to date.
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    BASS. XXXIV. A Catalog of the Nuclear Millimeter-wave Continuum Emission Properties of AGNs Constrained on Scales ≤ 100-200 pc
    (IOP Publishing Ltd, 2023) Kawamuro, Taiki; Ricci, Claudio; Mushotzky, Richard F.; Imanishi, Masatoshi; Bauer, Franz Erik; Ricci, Federica; Koss, Michael J.; Privon, George C.; Trakhtenbrot, Benny; Izumi, Takuma; Ichikawa, Kohei; Rojas, Alejandra F.; Smith, Krista Lynne; Shimizu, Taro; Oh, Kyuseok; den Brok, Jakob S.; Baba, Shunsuke; Balokovic, Mislav; Chang, Chin-Shin; Kakkad, Darshan; Pfeifle, Ryan W.; Temple, Matthew J.; Ueda, Yoshihiro; Harrison, Fiona; Powell, Meredith C.; Stern, Daniel; Urry, Meg; Sanders, David B.
    We present a catalog of the millimeter-wave (mm-wave) continuum properties of 98 nearby (z < 0.05) active galactic nuclei (AGNs) selected from the 70 month Swift/BAT hard-X-ray catalog that have precisely determined X-ray spectral properties and subarcsecond-resolution Atacama Large Millimeter/submillimeter Array Band 6 (211-275 GHz) observations as of 2021 April. Due to the hard-X-ray (>10 keV) selection, the sample is nearly unbiased for obscured systems at least up to Compton-thick-level obscuration, and provides the largest number of AGNs with high-physical-resolution mm-wave data (less than or similar to 100-200 pc). Our catalog reports emission peak coordinates, spectral indices, and peak fluxes and luminosities at 1.3 mm (230 GHz). Additionally, high-resolution mm-wave images are provided. Using the images and creating radial surface brightness profiles of mm-wave emission, we identify emission extending from the central sources and isolated blob-like emission. Flags indicating the presence of these emission features are tabulated. Among 90 AGNs with significant detections of nuclear emission, 37 AGNs (approximate to 41%) appear to have both or one of extended or blob-like components. We, in particular, investigate AGNs that show well-resolved mm-wave components and find that these seem to have a variety of origins (i.e., a jet, radio lobes, a secondary AGN, stellar clusters, a narrow-line region, galaxy disk, active star formation regions, or AGN-driven outflows), and some components have currently unclear origins.
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    BASS. XXXV. The MBH-σ* Relation of 105 Month Swift-BAT Type 1 AGNs
    (IOP Publishing Ltd, 2023) Caglar, Turgay; Koss, Michael J.; Burtscher, Leonard; Trakhtenbrot, Benny; Erdim, M. Kiyami; Mejia-Restrepo, Julian E.; Ricci, Federica; Powell, Meredith C.; Ricci, Claudio; Mushotzky, Richard; Bauer, Franz Erik; Ananna, Tonima T.; Baer, Rudolf E.; Brandl, Bernhard; Brinchmann, Jarle; Harrison, Fiona; Ichikawa, Kohei; Kakkad, Darshan; Oh, Kyuseok; Riffel, Rogerio; Sartori, Lia F.; Smith, Krista L.; Stern, Daniel; Urry, C. Megan
    We present two independent measurements of stellar velocity dispersions (sigma(star)) from the Ca II H+K lambda 3969, 3934 and Mg I b lambda 5183, 5172, 5167 region (3880-5550 angstrom) and the calcium triplet region (8350-8750 angstrom) for 173 hard X-ray-selected Type 1 active galactic nuclei (AGNs; z <= 0.08) from the 105 month Swift-BAT catalog. We construct one of the largest samples of local Type 1 AGNs that have both single-epoch virial black hole mass (M-BH) estimates and sigma(star) measurements obtained from high spectral resolution data, allowing us to test the usage of such methods for supermassive black hole studies. We find that the two independent sigma(star) measurements are highly consistent with each other, with an average offset of only 0.002 +/- 0.001 dex. Comparing M-BH estimates based on broad emission lines and stellar velocity dispersion measurements, we find that the former is systematically lower by approximate to 0.12 dex. Consequently, Eddington ratios estimated through broad-line MBH determinations are similarly biased (but in the opposite way). We argue that the discrepancy is driven by extinction in the broad-line region. We also find an anticorrelation between the offset from the M-BH-sigma(star) relation and the Eddington ratio. Our sample of Type 1 AGNs shows a shallower M-BH-sigma(star) relation (with a power-law exponent of approximate to 3.5) compared with that of inactive galaxies (with a power-law exponent of approximate to 4.5), confirming earlier results obtained from smaller samples.
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    BAT AGN Spectroscopic Survey. XX. Molecular Gas in Nearby Hard-X-Ray-selected AGN Galaxies
    (2021) Koss, Michael J. ; Strittmatter, Benjamin ; Lamperti, Isabella; Shimizu, Taro ; Trakhtenbrot, Benny ; Saintonge, Amelie ; Treister, Ezequiel ; Cicone, Claudia; Mushotzky, Richard ; Oh, Kyuseok; Ricci, Claudio ; Stern, Daniel ; Tasnim Ananna, Tonima ; Bauer, Franz Erik; Privon, George C. ; Bär, Rudolf ; De Breuck, Carlos; Harrison, Fiona ; Ichikawa, Kohei ; Powell, Meredith C. ; Rosario, David ; Sanders, David B. ; Schawinski, Kevin ; Shao, Li ; Urry, C. Megan ; Veilleux, Sylvain
    We present the host-galaxy molecular gas properties of a sample of 213 nearby (0.01.<.z.<.0.05) hard-X-rayselected active galactic nucleus (AGN) galaxies, drawn from the 70-month catalog of Swift's Burst Alert Telescope (BAT), with 200 new CO(2-1) line measurements obtained with the James Clerk Maxwell Telescope and the Atacama Pathfinder Experiment telescope. We find that AGN in massive galaxies (log(M*/M-circle dot) > 10.5) tend to have more molecular gas and higher gas fractions than inactive galaxies matched in stellar mass. When matched in star formation, we find AGN galaxies show no difference from inactive galaxies, with no evidence that AGN feedback affects the molecular gas. The higher molecular gas content is related to AGN galaxies hosting a population of gas-rich early types with an order of magnitude more molecular gas and a smaller fraction of quenched, passive galaxies (similar to 5% versus 49%) compared to inactive galaxies. The likelihood of a given galaxy hosting an AGN (L-bol > 10(44) erg s(-1)) increases by similar to 10-100 between a molecular gas mass of 10(8.7)M(circle dot) and 10(10.2)M(circle dot). AGN galaxies with a higher Eddington ratio (log(L/L-Edd) > -1.3) tend to have higher molecular gas masses and gas fractions. The log(N-H/cm(-2)) > 23.4) of AGN galaxies with higher column densities are associated with lower depletion timescales and may prefer hosts with more gas centrally concentrated in the bulge that may be more prone to quenching than galaxy-wide molecular gas. The significant average link of host-galaxy molecular gas supply to supermassive black hole (SMBH) growth may naturally lead to the general correlations found between SMBHs and their host galaxies, such as the correlations between SMBH mass and bulge properties, and the redshift evolution of star formation and SMBH growth.
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    Evolution of the dual AGN in Mrk 266: a young AGN and a rotation-dominated disc in the SW nucleus
    (2024) Ruby, Mason; Muller-Sanchez, Francisco; Comerford, Julia M.; Stern, Daniel; Cales, Sabrina L.; Harrison, Fiona; Malkan, Matthew A.; Privon, George C.; Treister, Ezequiel
    Dual active galactic nuclei (AGNs) offer a unique opportunity to probe the relationship between supermassive black holes (SMBH) and their host galaxies as well as the role of major mergers in triggering AGN activity. The confirmed dual AGN Mrk 266 has been studied extensively with multiwavelength imaging. Now, high-spatial-resolution IFU spectroscopy of Mrk 266 provides an opportunity to probe the kinematics of both the merger event and AGN feedback. We present for the first time high-spatial-resolution kinematic maps for both nuclei of Mrk 266 obtained with the Keck OSIRIS IFU spectrograph, utilizing adaptive optics to achieve a resolution of 0.31 and 0.20arcsec for the NE and SW nuclei, respectively. Using the MBH-sigma & lowast; relation for mergers, we infer an SMBH mass of approximately 7x10(7)M(circle dot) for the south-western nucleus. Additionally, we report that the molecular gas kinematics of the south-western nucleus are dominated by rotation rather than large-scale chaotic motions. The south-west nucleus also contains both a circumnuclear ring of star formation from which an inflow of molecular gas is likely fuelling the AGN and a compact, AGN-dominated outflow of highly ionized gas with a time-scale of approximately 2 Myr, significantly shorter than the time-scale of the merger. The north-eastern nucleus, on the other hand, exhibits complex kinematics related to the merger, including molecular gas that appears to have decoupled from the rotation of the stars. Our results suggest that while the AGN activity in Mrk 266 was likely triggered during the merger, AGN feeding is currently the result of processes internal to each host galaxy, thus resulting in a strong asymmetry between the two nuclei.
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    Probing the Structure and Evolution of BASS Active Galactic Nuclei through Eddington Ratios
    (2022) Ananna, Tonima Tasnim; Urry, C. Megan; Ricci, Claudio; Natarajan, Priyamvada; Hickox, Ryan C.; Trakhtenbrot, Benny; Treister, Ezequiel; Weigel, Anna K.; Ueda, Yoshihiro; Koss, Michael J.; Bauer, F. E.; Temple, Matthew J.; Balokovic, Mislav; Mushotzky, Richard; Auge, Connor; Sanders, David B.; Kakkad, Darshan; Sartori, Lia F.; Marchesi, Stefano; Harrison, Fiona; Stern, Daniel; Oh, Kyuseok; Caglar, Turgay; Powell, Meredith C.; Podjed, Stephanie A.; Mejia-Restrepo, Julian E.
    We constrain the intrinsic Eddington ratio (lambda(Edd)) distribution function for local active galactic nuclei (AGN) in bins of low and high obscuration [log(N-H/cm(-2)) <= 22 and 22 < log(N-H/cm(-2)) < 25], using the Swift Burst Alert Telescope 70 month/BASS DR2 survey. We interpret the fraction of obscured AGN in terms of circumnuclear geometry and temporal evolution. Specifically, at low Eddington ratios (log lambda(Edd) < -2), obscured AGN outnumber unobscured ones by a factor of similar to 4, reflecting the covering factor of the circumnuclear material (0.8, or a torus opening angle of similar to 34 degrees). At high Eddington ratios (log lambda(Edd) > - 1), the trend is reversed, with <30% of AGN having log(N-H/cm(-2)) > 22, which we suggest is mainly due to the small fraction of time spent in a highly obscured state. Considering the Eddington ratio distribution function of narrow-line and broad-line AGN from our prior work, we see a qualitatively similar picture. To disentangle temporal and geometric effects at high lambda(Edd), we explore plausible clearing scenarios such that the time-weighted covering factors agree with the observed population ratio. We find that the low fraction of obscured AGN at high lambda(Edd) is primarily due to the fact that the covering factor drops very rapidly, with more than half the time spent with <10% covering factor. We also find that nearly all obscured AGN at high-lambda(Edd) exhibit some broad lines. We suggest that this is because the height of the depleted torus falls below the height of the broad-line region, making the latter visible from all lines of sight.
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    The NuSTAR Serendipitous Survey: The 80 Month Catalog and Source Properties of the High-energy Emitting Active Galactic Nucleus and Quasar Population
    (2024) Greenwell, Claire L.; Klindt, Lizelke; Lansbury, George B.; Rosario, David J.; Alexander, David M.; Aird, James; Stern, Daniel; Forster, Karl; Koss, Michael J.; Bauer, Franz E.; Ricci, Claudio; Tomsick, John; Brandt, William N.; Connor, Thomas; Boorman, Peter G.; Annuar, Adlyka; Ballantyne, David R.; Chen, Chien-Ting; Civano, Francesca; Comastri, Andrea; Fawcett, Victoria A.; Fornasini, Francesca M.; Gandhi, Poshak; Harrison, Fiona; Heida, Marianne; Hickox, Ryan; Kammoun, Elias S.; Lanz, Lauranne; Marchesi, Stefano; Noirot, Gael; Romero-Colmenero, Encarni; Treister, Ezequiel; Urry, C. Megan; Vaisanen, Petri; van Soelen, Brian
    We present a catalog of hard X-ray serendipitous sources detected in the first 80 months of observations by the Nuclear Spectroscopic Telescope Array (NuSTAR). The NuSTAR serendipitous survey 80 month (NSS80) catalog has an unprecedented similar to 62 Ms of effective exposure time over 894 unique fields (a factor of 3 increase over the 40 month catalog, NSS40), with an areal coverage of similar to 36 deg(2), larger than all NuSTAR extragalactic surveys. NSS80 provides 1274 hard X-ray sources in the 3-24 keV band (822 new detections compared to the previous NSS40). Approximately 76% of the NuSTAR sources have lower-energy (<10 keV) X-ray counterparts from Chandra, XMM-Newton, and Swift-XRT. We have undertaken an extensive campaign of ground-based spectroscopic follow-up to obtain new source redshifts and classifications for 427 sources. Combining these with existing archival spectroscopy provides redshifts for 550 NSS80 sources, of which 547 are classified. The sample is primarily composed of active galactic nuclei (AGNs), detected over a large range in redshift (z = 0.012-3.43), but also includes 58 spectroscopically confirmed Galactic sources. In addition, five AGN-galaxy pairs, one dual AGN system, one BL Lac candidate, and a hotspot of 4C 74.26 (radio quasar) have been identified. The median rest-frame 10-40 keV luminosity and redshift of NSS80 are < L10-40 keV > = 1.2 x 10(44) erg s(-1) and < z > = 0.56. We investigate the optical properties and construct composite optical spectra to search for subtle signatures not present in the individual spectra, finding an excess of redder BL AGNs compared to optical quasar surveys, predominantly due to the presence of the host galaxy and, at least in part, due to dust obscuration.