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Abstract 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. 

Abstract Understanding the interplay of stellar feedback and turbulence in the interstellar medium (ISM) is essential to modeling the evolution of galaxies. To determine the timescales over which stellar feedback drives turbulence in the ISM, we performed a spatially resolved, multiwavelength study of the nearby star-forming dwarf galaxy UGC 4305. As indicators of turbulence on local scales (400 pc), we utilized ionized gas velocity dispersion derived from IFU Hαobservations and atomic gas velocity dispersion and energy surface densities derived from Hisynthesis observations with the Very Large Array. These indicators of turbulence were tested against star formation histories over the past 560 Myr derived from color–magnitude diagrams using Spearman’s rank correlation coefficient. The strongest correlation identified at the 400 pc scale is between measures of Hiturbulence and star formation 70–140 Myr ago. We repeated our analysis of UGC 4305's current turbulence and past star formation activity on multiple physical scales (∼560 and 800 pc) to determine whether there are indications of changes in the correlation timescale with changes to the physical scale. No notable correlations were found at larger physical scales, emphasizing the importance of analyzing star formation-driven turbulence as a local phenomenon.