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Abstract We present the stellar dynamical (SD) mass of the central black hole in the nearby Seyfert galaxy MCG–06-30-15 using the Schwarzschild orbit-superposition method implemented in the open-source codeFORSTAND. We obtained spatially resolvedK-band nuclear stellar spectra for this galaxy with SINFONI on the Very Large Telescope. We extracted the bulk stellar kinematics using Gauss–Hermite (GH) parameterization of the line-of-sight velocity distributions. A multicomponent surface-brightness profile of the galaxy was determined from a Hubble Space Telescope medium-bandVimage. Our best-fit models indicate a black hole mass ofM_BH = (4.4 ± 1.4) × 10⁷M_⊙and a stellar mass-to-light ratio ofM/L= (3.0 ± 0.3)M_⊙/L_⊙, within 1σconfidence intervals. Our constraint onM_BHagrees with an upper limit on the mass from stellar dynamics based on the Jeans anisotropic modeling method, but is ∼10 times larger than the reported mass from reverberation mapping (RM). However, our best-fitM_BHmay be systematically biased high due to the counterrotating disk in the nucleus of MCG–06-30-15 and the inability of the GH parameterization to fully describe such a complicated set of stellar kinematics. In addition, a dynamicalM_BHvalue depends heavily on the assumed source distance, which is not yet accurately constrained for this galaxy. MCG–06-30-15 is only the fourth galaxy in which we can compareM_BHfrom SD modeling with that from RM. A direct comparison ofM_BHallows us to identify and investigate the possible sources of bias associated with different mass measurement techniques, which may influence our understanding of black hole and galaxy coevolution across cosmological timescales. 

We report the discovery of an extremely high-velocity outflow (EHVO) in the most luminous QSO (L_Bol∼ 2.29 × 10⁴⁸erg/s), named SMSS J2157-3602, atz = 4.692. Combined XSHOOTER and NIRES observations reveal that the EHVO reaches a maximum velocity ofv_max ∼ 0.13cand persists over rest-frame timescales of a few months up to one year. SMSS J2157-3602 also exhibits one of the highest balnicity index values discovered for an EHVO so far. In addition, the blueshifted CIV emission traces a high-velocity (v_CIV⁵⁰∼ 4660 km/s) outflow from the broad-line region (BLR). Thanks to an XMM-Newton observation, we were also able to reveal the X-ray weak nature of this QSO, which likely prevents the overionization of the innermost disk atmosphere and facilitates the efficient launch of the detected EHVO and BLR winds. The extraordinary luminosity of SMSS J2157-3602 and the extreme velocity of the EHVO make it a unique laboratory for testing active galactic nucleus (AGN) driven feedback under extreme conditions. Current uncertainties on the outflow’s location and column density strengthen the case for a dedicated follow-up, which will be essential to assess the full feedback potential of this remarkable quasar. 

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 We present a new constraint on the mass of the black hole in the active S0 galaxy NGC 5273. Due to the proximity of the galaxy at 16.6 ± 2.1 Mpc, we were able to resolve and extract the bulk motions of stars near the central black hole using adaptive-optics-assisted observations with the Gemini Near-infrared Integral Field Spectrograph, as well as constrain the large-scale kinematics using archival Spectroscopic Areal Unit for Research and Optical Nebulae spectroscopy. High-resolution Hubble Space Telescope imaging allowed us to generate a surface-brightness decomposition, determine approximate mass-to-light ratios for the bulge and disk, and obtain an estimate for the disk inclination. We constructed an extensive library of dynamical models using the Schwarzschild orbit-superposition code FORSTAND, exploring a range of disk and bulge shapes, halo masses, etc. We determined a black hole mass of M • = [0.5–2] × 10 7 M ⊙ , where the low side of the range is in agreement with the reverberation mapping measurement of M • = [4.7 ± 1.6] × 10 6 M ⊙ . NGC 5273 is one of the few nearby galaxies that hosts a broad-lined active galactic nucleus, allowing a crucial comparison of black hole masses derived from independent mass-measurement techniques. 

Abstract We present the results of a new reverberation mapping campaign for the broad-line active galactic nucleus (AGN) in the edge-on spiral IC 4329A. Monitoring of the optical continuum with V- band photometry and broad emission-line flux variability with moderate-resolution spectroscopy allowed emission-line light curves to be measured for H β , H γ , and He ii λ 4686. We find a time delay of 16.3 − 2.3 + 2.6 days for H β , a similar time delay of 16.0 − 2.6 + 4.8 days for H γ , and an unresolved time delay of − 0.6 − 3.9 + 3.9 days for He ii . The time delay for H β is consistent with the predicted value from the relationship between AGN luminosity and broad-line region radius, after correction for the ∼2.4 mag of intrinsic extinction at 5100 Å. Combining the measured time delay for H β with the broad emission-line width and an adopted value of 〈 f 〉 = 4.8, we find a central supermassive black hole mass of M BH = 6.8 − 1.1 + 1.2 × 10 7 M ⊙ . Velocity-resolved time delays were measured across the broad H β emission-line profile and may be consistent with an “M”-like shape. Modeling of the full reverberation response of H β was able to provide only modest constraints on some parameters, but does exhibit agreement with the black hole mass and average time delay. The models also suggest that the AGN structure is misaligned by a large amount from the edge-on galaxy disk. This is consistent with expectations from the unified model of AGNs, in which broad emission lines are expected to be visible only for AGNs that are viewed at relatively face-on inclinations. 

Abstract We present precise photometric estimates of stellar parameters, including effective temperature, metallicity, luminosity classification, distance, and stellar age, for nearly 26 million stars using the methodology developed in the first paper of this series, based on the stellar colors from the Stellar Abundances and Galactic Evolution Survey (SAGES) Data Release 1 and Gaia Early Data Release 3. The optimal design of stellar-parameter sensitiveuvfilters by SAGES has enabled us to determine photometric-metallicity estimates down to −3.5, similar to our previous results with the SkyMapper Southern Survey (SMSS), yielding a large sample of over five million metal-poor ([Fe/H] ≤ −1.0) stars and nearly one million very metal-poor ([Fe/H] ≤ −2.0) stars. The typical precision is around 0.1 dex for both dwarf and giant stars with [Fe/H] > −1.0, and 0.15–0.25/0.3–0.4 dex for dwarf/giant stars with [Fe/H] < −1.0. Using the precise parallax measurements and stellar colors from Gaia, effective temperature, luminosity classification, distance, and stellar age are further derived for our sample stars. This huge data set in the Northern sky from SAGES, together with similar data in the Southern sky from SMSS, will greatly advance our understanding of the Milky Way, in particular its formation and evolution. 

ABSTRACT We search for ultraluminous Quasi-Stellar Objects (QSOs) at high redshift using photometry from the SkyMapper Southern Survey Data Release 3 (DR3), in combination with 2MASS, VHS DR6, VIKING DR5, AllWISE, and CatWISE2020, as well as parallaxes and proper motions from Gaia DR2 and eDR3. We report 142 newly discovered Southern QSOs at 3.8 < z < 5.5, of which 126 have M145 < −27 AB mag and are found in a search area of 14 486 deg2. This Southern sample, utilizing the Gaia astrometry to offset wider photometric colour criteria, achieves unprecedented completeness for an ultraluminous QSO search at high redshift. In combination with already known QSOs, we construct a sample that is >80 per cent complete for M145 < −27.33 AB mag at z = 4.7 and for M145 < −27.73 AB mag at z = 5.4. We derive the bright end of the QSO luminosity function at rest frame 145 nm for z = 4.7–5.4 and measure its slope to be β = −3.60 ± 0.37 and β = −3.38 ± 0.32 for two different estimates of the faint-end QSO density adopted from the literature. We also present the first z ∼ 5 QSO luminosity function at rest frame 300 nm.