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Abstract The virial coefficient (f), which is meant to encapsulate broad-line region (BLR) geometry and kinematics, remains one of the largest sources of systematic uncertainty in black hole mass estimates for active galactic nuclei (AGNs). While the use of a sample average 〈f〉 enables black hole mass estimates across large samples and cosmological distances, individual AGNs may deviate from this average due to differences in BLR structure and viewing angle. In previous work, we reported marginal evidence for a correlation betweenfand the shape of the broad Hβemission line, ${\log }_{10}(\mathrm{FWHM}/\sigma )$. In this work, we update our sample to include 10 new sources withCARAMELBLR dynamical modeling, increasing both the black hole mass range and statistical power of our analysis. We find marginal evidence for a correlation betweenfand ${\log }_{10}(\mathrm{FWHM}/\sigma )$, with a slope and intrinsic scatter consistent with previous results. The confirmation of this trend across a larger sample further supports the idea that line profile shape may reflect BLR properties in a way that directly impactsf. If confirmed with future BLR dynamical modeling of sources within a wider range of ${\log }_{10}(\mathrm{FWHM}/\sigma )$, this relationship could enable empirical estimates of the virial coefficient and improve single-epoch black hole mass estimates across cosmic time. 

Abstract Reverberation mapping (RM) determines the mass of black holes (BHs) in active galactic nuclei (AGNs) by resolving the BH gravitational sphere of influence in the time domain. Recent RM campaigns have yielded direct BH masses through dynamical modeling for a sample of 32 objects, spanning a wide range of AGN luminosities and BH masses. In addition, accurate BH masses have been determined by spatially resolving the broad-line region with GRAVITY for a handful of AGNs. Here, we present a detailed analysis of Hubble Space Telescope images using surface-brightness profile fitting with state-of-the-art programs. We derive AGN luminosity and host-galaxy properties, such as radii and luminosities for the spheroid, disk, and bar (if present). The spheroid effective radii are used to measure stellar velocity dispersion from integral-field spectroscopy. Since the BH masses of our sample do not depend on any assumption of the virial factor needed in single-epoch spectroscopic mass estimates, we can show that the resulting scaling relations between the mass of the supermassive BHs and their host galaxies match those of quiescent galaxies, naturally extending to lower masses in these (predominantly) spiral galaxies. We find that the inner AGN orientation, as traced by the broad-line region inclination angle, is uncorrelated with the host-galaxy disk. Our sample has the most direct and accurateM_BH measurements of any AGN sample and provides a fundamental local benchmark for studies of the evolution of massive BHs and their host galaxies across cosmic time. 

Abstract We present optical integral-field spectroscopic data of ten nearby (0.02 ≤z≤ 0.05) Seyfert 1 galaxies taken with the Keck Cosmic Web Imager. We map the spatially resolved kinematics of the [Oiii] gas and stars, and investigate the alignments between their global kinematic position angles (PAs). Large-scale gas motions are primarily dominated by rotation and are kinematically aligned with the stars (ΔPA ≤ 30°). However, eight galaxies exhibit nonrotational kinematic signatures (e.g., kinematic twists, possible outflows) in their ionized gas velocity fields near the nucleus. We compare aperture-wide measurements of the gas and stellar velocity dispersions (σ_gasandσ_⋆) to test the use of the width of the [Oiii] line core as a surrogate forσ_⋆. Direct comparisons betweenσ_gasandσ_⋆show thatσ_gastends to underestimateσ_⋆, and thus is not a reliable tracer ofσ_⋆for our selected galaxies. We measure the extent of the narrow-line region (NLR) using several definitions, resulting in sizes of ∼0.1–10 kpc. For a given [Oiii] luminosity, our NLR sizes derived from the [Oiii]/Hβflux ratio or an [Oiii] isophotal radius are an order of magnitude larger than those measured from past imaging data. 

Abstract The radial gradient of gas-phase metallicity is a powerful probe of the chemical and structural evolution of star-forming galaxies, closely tied to disk formation and gas kinematics in the early Universe. We present spatially resolved chemical and dynamical properties for a sample of 25 galaxies at 0.5 ≲ z ≲ 1.7 from theMSA-3Dsurvey. These innovative observations provide 3D spectroscopy of galaxies at a spatial resolution approaching JWST’s diffraction limit and a high spectral resolution ofR ≃ 2700. The metallicity gradients measured in our galaxy sample range from −0.03 to 0.02 dex kpc⁻¹. Most galaxies exhibit negative or flat radial gradients, indicating lower metallicity in the outskirts or uniform metallicity throughout the entire galaxy. We confirm a tight relationship between stellar mass and metallicity gradient atz ∼ 1 with small intrinsic scatter of 0.02 dex kpc⁻¹. Our results indicate that metallicity gradients become increasingly negative as stellar mass increases, likely because the more massive galaxies tend to be more “disky.” This relationship is consistent with the predictions from cosmological hydrodynamic zoom-in simulations with strong stellar feedback. This work presents the effort to harness the multiplexing capability of the JWST NIRSpec microshutter assembly in slit-stepping mode to map the chemical and kinematic profiles of high-redshift galaxies in large samples and at high spatial and spectral resolution. 

Abstract We present the second iteration of thecaramel-gascode, an empirical model of the broad-line region (BLR) gas density field. Building on the initial development and testing ofcaramel-gas, we expand the meaning of the model parameterα, which initially represented only the power-law index of the dependency of emissivity on radial distance. In this work, we test a more generalized radial power-law index,α, that also includes a description of the effective emitting size(s) of the BLR structure as a function of radial distance. We select a sample of 10 active galactic nuclei (AGN) from three different Lick AGN Monitoring Project campaigns to further validate thecaramel-gascode and test the generalized radial power-law index,α. Our results confirm that thecaramel-gasresults are in general agreement with the published results determined using the originalcaramelcode, further demonstrating that our forward modeling method is robust. We find that a positive radial power-law index is generally favored and propose three possible scenarios: (i) the BLR structure has increasing effective emitting size(s) at larger radial distances from the central source, (ii) emission is concentrated at the outer edges of the BLR, and (iii) stronger theoretical assumptions are needed to break the degeneracies inherent to the interpretation of reverberation mapping data in terms of underlying gas properties. 

Abstract We present high-resolution Keck Cosmic Web Imager and MUSE integral field unit spectroscopy of VV 114, a local IR-luminous merger undergoing a vigorous starburst and showing evidence of galactic-scale feedback. The high-resolution data allow for spectral deblending of the optical emission lines and reveal a broad emission line component (σ_broad ∼ 100–300 km s⁻¹) with line ratios and kinematics consistent with a mixture of ionization by stars and radiative shocks. The shock fraction (percentage of ionization due to shocks) in the high-velocity gas is anticorrelated with the projected surface number density of resolved star clusters, and we find that the radial density profiles around clusters are fit well by models of adiabatically expanding cluster winds driven by massive stellar winds and supernovae (SNe). The total kinetic power estimated from the cluster wind models matches the wind + SN mechanical energy deposition rate estimated from the soft-band X-ray luminosity, indicating that at least 70% of the shock luminosity in the galaxy is driven by the star clusters. Hubble Space Telescope narrowband near-IR imaging reveals embedded shocks in the dust-buried IR nucleus of VV 114E. Most of the shocked gas is blueshifted with respect to the quiescent medium, and there is a close spatial correspondence between the shock map and the Chandra soft-band X-ray image, implying the presence of a galactic superwind. The energy budget of the superwind is in close agreement with the total kinetic power of the cluster winds, confirming the superwind is driven by the starburst. 

To reproduce observed galaxy properties, cosmological simulations require that massive galaxies experience feedback from active galactic nuclei, which regulates star formation within those galaxies. However, the energetics and timescales of these feedback processes are poorly constrained. We combined optical, infrared, submillimeter, and radio observations of the active galaxy VV 340a, which is hosting a low-power jet launched from a supermassive black hole at its center. We found that the jet undergoes precession, with a period of (8.2 ± 5.5) × 10⁵years, and drives an outflow of gas at a rate of 19.4 ± 7.9 solar masses per year. The jet shocks the gas, producing highly ionized plasma that extends several kiloparsecs from the nucleus. The outflow ejects sufficient gas from the galaxy to influence its star-formation rate. 

Abstract We introduce a prescription for estimating the flux of the 7.7μm and 11.3μm polycyclic aromatic hydrocarbon (PAH) features from broadband JWST/MIRI images. Probing PAH flux with MIRI imaging data has advantages in field of view, spatial resolution, and sensitivity compared with MIRI spectral maps, but comparisons with spectra are needed to calibrate these flux estimations over a wide variety of environments. For 267 MIRI/MRS spectra from independent regions in the four luminous infrared galaxies (LIRGs) in the Great Observatories All-sky LIRG Survey Early Release Science program, we derive synthetic filter photometry and directly compare estimated PAH fluxes to those measured from detailed spectral fits. We find that for probing PAH 7.7μm, the best combination of filters is F560W, F770W, and either F1500W or F2100W, and the best for PAH 11.3μm is F560W, F1000W, F1130W, and F1500W. The prescription with these combinations yields predicted flux densities that typically agree with values from spectral decomposition within ∼7% and ∼5% for PAH 7.7 and 11.3μm, respectively. 

Abstract Observed scatter in the Lyαopacity of quasar sightlines atz< 6 has motivated measurements of the correlation between Lyαopacity and galaxy density, as models that predict this scatter make strong and sometimes opposite predictions for how they should be related. Our previous work associated two highly opaque Lyαtroughs atz∼ 5.7 with a deficit of Lyαemitting galaxies (LAEs). In this work, we survey two of the most highly transmissive lines of sight at this redshift toward thez= 6.02 quasar SDSS J1306+0356 and thez= 6.17 quasar PSO J359-06. We find that both fields are underdense in LAEs within 10h⁻¹Mpc of the quasar sightline, somewhat less extensive than underdensities associated with Lyαtroughs. We combine our observations with three additional fields from the literature and find that while fields with extreme opacities are generally underdense, moderate opacities span a wider density range. The results at high opacities are consistent with models that invoke UV background fluctuations and/or late reionization to explain the observed scatter in intergalactic medium (IGM) Lyαopacities. There is tension at low opacities, however, as the models tend to associate lower IGM Lyαopacities with higher densities. Although the number of fields surveyed is still small, the low-opacity results may support a scenario in which the ionizing background in low-density regions increases more rapidly than some models suggest after becoming ionized. Elevated gas temperatures from recent reionization may also be making these regions more transparent. 

Abstract The fourth Fermi Large Area Telescope catalog (4FGL) contains 5064 γ -ray sources detected at high significance, but 26% of them still lack associations at other wavelengths. The SPT-SZ survey, conducted between 2008 and 2011 with the South Pole Telescope (SPT), covers 2500 deg 2 of the southern sky in three millimeter-wavelength (mm) bands and was used to construct a catalog of nearly 5000 emissive sources. In this study, we introduce a new cross-matching scheme to search for multiwavelength counterparts of extragalactic γ -ray sources using a mm catalog. We apply a Poissonian probability to evaluate the rate of spurious false associations and compare the multiwavelength associations from the radio, mm, near-infrared, and X-ray with 4FGL γ -ray sources. In the SPT-SZ survey field, 85% of 4FGL sources are associated with mm counterparts. These mm sources include 94% of previously associated 4FGL sources and 56% of previously unassociated 4FGL sources. The latter group contains 40 4FGL sources for which SPT has provided the first identified counterparts. Nearly all of the SPT-associated 4FGL sources can be described as flat-spectrum radio quasars or blazars. We find that the mm band is the most efficient wavelength for detecting γ -ray blazars when considering both completeness and purity. We also demonstrate that the mm band correlates better to the γ -ray band than the radio or X-ray bands. With the next generation of CMB experiments, this technique can be extended to greater sensitivities and more sky area to further complete the identifications of the remaining unknown γ -ray blazars.