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1. The Lick AGN Monitoring Project 2016: Velocity-resolved Hβ Lags in Luminous Seyfert Galaxies

   https://doi.org/10.3847/1538-4357/ac3d26  

   U, Vivian ; Barth, Aaron J. ; Vogler, H. Alexander ; Guo, Hengxiao ; Treu, Tommaso ; Bennert, Vardha N. ; Canalizo, Gabriela ; Filippenko, Alexei V. ; Gates, Elinor ; Hamann, Frederick ; et al ( January 2022 , The Astrophysical Journal)

   We carried out spectroscopic monitoring of 21 low-redshift Seyfert 1 galaxies using the Kast double spectrograph on the 3 m Shane telescope at Lick Observatory from 2016 April to 2017 May. Targeting active galactic nuclei (AGNs) with luminosities ofλL_λ(5100 Å) ≈ 10⁴⁴erg s⁻¹and predicted Hβlags of ∼20–30 days or black hole masses of 10⁷–10^8.5M_⊙, our campaign probes luminosity-dependent trends in broad-line region (BLR) structure and dynamics as well as to improve calibrations for single-epoch estimates of quasar black hole masses. Here we present the first results from the campaign, including Hβemission-line light curves, integrated Hβlag times (8–30 days) measured againstV-band continuum light curves, velocity-resolved reverberation lags, line widths of the broad Hβcomponents, and virial black hole mass estimates (10^7.1–10^8.1M_⊙). Our results add significantly to the number of existing velocity-resolved lag measurements and reveal a diversity of BLR gas kinematics at moderately high AGN luminosities. AGN continuum luminosity appears not to be correlated with the type of kinematics that its BLR gas may exhibit. Follow-up direct modeling of this data set will elucidate the detailed kinematics and provide robust dynamical black hole masses for several objects in this sample.

    

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2. CARAMEL-gas: A Step toward Fast Empirical Models of the Broad-line-emitting Gas

   https://doi.org/10.3847/1538-4357/ac8164  

   Williams, Peter R. ; Treu, Tommaso ( August 2022 , The Astrophysical Journal)

   Fast empirical models of the broad emission line region (BLR) are a powerful tool to interpret velocity-resolved reverberation mapping (RM) data, estimate the mass of the supermassive black holes, and gain insight into its geometry and kinematics. Much of the effort so far has been devoted to describing the emissivity of one emission line at a time. We present here an alternative approach aimed at describing the underlying BLR gas distribution, by exploiting simple numerical recipes to connect it with emissivity. This approach is a step toward describing multiple emission lines originating from the same gas and allows us to clarify some issues related to the interpretation of RM data. We illustrate this approach—implemented in the codeCARAMEL-gas—using three data sets covering the Hβemission line (Mrk 50, Mrk 1511, Arp 151) that have been modeled using the emissivity-based version of the code. As expected, we find differences in the parameters describing the BLR gas and emissivity distribution, but the emissivity-weighted lag measurements and all other model parameters including black hole mass and overall BLR morphology and kinematics are consistent with the previous measurements. We also model the Hαemission line for Arp 151 using both the gas- and emissivity-based BLR models. We find ionization stratification in the BLR with Hαarising at larger radii than Hβ, while all other model parameters are consistent within the uncertainties.

    

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3. Velocity-resolved Reverberation Mapping of NGC 3227

   https://doi.org/10.3847/1538-4357/ad08b8  

   Bentz, Misty C. ; Markham, Madison ; Rosborough, Sara ; Onken, Christopher A. ; Street, Rachel ; Valluri, Monica ; Treu, Tommaso ( December 2023 , The Astrophysical Journal)

   We describe the results of a new reverberation mapping program focused on the nearby Seyfert galaxy NGC 3227. Photometric and spectroscopic monitoring was carried out from 2022 December to 2023 June with the Las Cumbres Observatory network of telescopes. We detected time delays in several optical broad emission lines, with Hβhaving the longest delay at${\tau }_{\mathrm{cent}}={4.0}_{-0.9}^{+0.9}$days and Heiihaving the shortest delay with${\tau }_{\mathrm{cent}}={0.9}_{-0.8}^{+1.1}$days. We also detect velocity-resolved behavior of the Hβemission line, with different line-of-sight velocities corresponding to different observed time delays. Combining the integrated Hβtime delay with the width of the variable component of the emission line and a standard scale factor suggests a black hole mass of$M_{\mathrm{BH}}={1.1}_{-0.3}^{+0.2}\times {10}^7$M_⊙. Modeling of the full velocity-resolved response of the Hβemission line with the phenomenological codeCARAMELfinds a similar mass of$M_{\mathrm{BH}}={1.2}_{-0.7}^{+1.5}\times {10}^7$M_⊙and suggests that the Hβ-emitting broad-line region (BLR) may be represented by a biconical or flared disk structure that we are viewing at an inclination angle ofθ_i≈ 33° and with gas motions that are dominated by rotation. The new photoionization-based BLR modeling toolBELMACfinds general agreement with the observations when assuming the best-fitCARAMELresults; however,BELMACprefers a thick-disk geometry and kinematics that are equally composed of rotation and inflow. Both codes infer a radially extended and flattened BLR that is not outflowing.

    

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4. Supermassive Black Holes with High Accretion Rates in Active Galactic Nuclei. XIII. Ultraviolet Time Lag of Hβ Emission in Mrk 142

   https://doi.org/10.3847/1538-4357/acfb72  

   Khatu, Viraja C. ; Gallagher, Sarah C. ; Horne, Keith ; Cackett, Edward M. ; Hu, Chen ; Pasquini, Sofia ; Hall, Patrick ; Wang, Jian-Min ; Bian, Wei-Hao ; Li, Yan-Rong ; et al ( November 2023 , The Astrophysical Journal)

   We performed a rigorous reverberation-mapping analysis of the broad-line region (BLR) in a highly accreting (L/L_Edd= 0.74–3.4) active galactic nucleus, Markarian 142 (Mrk 142), for the first time using concurrent observations of the inner accretion disk and the BLR to determine a time lag for the Hβλ4861 emission relative to the ultraviolet (UV) continuum variations. We used continuum data taken with the Niel Gehrels Swift Observatory in theUVW2 band, and the Las Cumbres Observatory, Dan Zowada Memorial Observatory, and Liverpool Telescope in thegband, as part of the broader Mrk 142 multiwavelength monitoring campaign in 2019. We obtained new spectroscopic observations covering the Hβbroad emission line in the optical from the Gemini North Telescope and the Lijiang 2.4 m Telescope for a total of 102 epochs (over a period of 8 months) contemporaneous to the continuum data. Our primary result states a UV-to-Hβtime lag of${8.68}_{-0.72}^{+0.75}$days in Mrk 142 obtained from light-curve analysis with a Python-based running optimal average algorithm. We placed our new measurements for Mrk 142 on the optical and UV radius–luminosity relations for NGC 5548 to understand the nature of the continuum driver. The positions of Mrk 142 on the scaling relations suggest that UV is closer to the “true” driving continuum than the optical. Furthermore, we obtain$\log (M_{•}/M_{\odot })$= 6.32 ± 0.29 assuming UV as the primary driving continuum.

    

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5. A geometric distance to the supermassive black Hole of NGC 3783

   https://doi.org/10.1051/0004-6361/202141426  

   Amorim, A. ; Bauböck, M. ; Bentz, M. C. ; Brandner, W. ; Bolzer, M. ; Clénet, Y. ; Davies, R. ; de Zeeuw, P. T. ; Dexter, J. ; Drescher, A. ; et al ( October 2021 , Astronomy & Astrophysics)

   null (Ed.)

   The angular size of the broad line region (BLR) of the nearby active galactic nucleus NGC 3783 has been spatially resolved by recent observations with VLTI/GRAVITY. A reverberation mapping (RM) campaign has also recently obtained high quality light curves and measured the linear size of the BLR in a way that is complementary to the GRAVITY measurement. The size and kinematics of the BLR can be better constrained by a joint analysis that combines both GRAVITY and RM data. This, in turn, allows us to obtain the mass of the supermassive black hole in NGC 3783 with an accuracy that is about a factor of two better than that inferred from GRAVITY data alone. We derive M BH = 2.54 −0.72 +0.90 × 10 7 M ⊙ . Finally, and perhaps most notably, we are able to measure a geometric distance to NGC 3783 of 39.9 −11.9 +14.5 Mpc. We are able to test the robustness of the BLR-based geometric distance with measurements based on the Tully–Fisher relation and other indirect methods. We find the geometric distance is consistent with other methods within their scatter. We explore the potential of BLR-based geometric distances to directly constrain the Hubble constant, H 0 , and identify differential phase uncertainties as the current dominant limitation to the H 0 measurement precision for individual sources. 

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