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The large- and small-scale environments around optically-selected AGN host galaxies and a control sample of non-active galaxies in the MaNGA survey have been investigated in order to evaluate the importance of the environment in AGN triggering. Using the MaNGA integral field spectroscopy, we quantify non-circular motions of the ionized gas and detect an excess of radial gas motions in AGN hosts relative to control galaxies, not associated to AGN feedback and are most likely the result of tidal interactions, possibly associated with the triggering of the AGN. We find that the large-scale environments are similar for the AGN hosts and control galaxies in our sample and are biased towards lower large-scale densities and group virial masses, suggestive that the large-scale environment properties is only relevant to the AGN phenomenon in an indirect way, in the form, e.g. of the morphology-density relation. The small-scale environment, as measured by the frequency and luminosity of close neighbours, was also found to be similar for AGN and control galaxies. However, we find a correlation between the intensity of the non-circular gas motions in AGN hosts and the strength of the tidal field, while the control sample does not present such correlation. Also, AGN hosts with the most intense radial gas motions present larger tidal fields than their control galaxies. These findings indicate that at least a fraction of the AGN hosts in our sample have been triggered by tidal interactions with nearby galaxies.

 

We use Gemini integral field unit observations to map the stellar population properties in the inner region (∼680 × 470 pc2) of the galaxy NGC 6868. In order to understand the physical and chemical properties of the stellar content of this galaxy, we performed stellar population synthesis using the starlight code with the MILES simple stellar population models. We measured the absorption line indices Fe4383, Mg2, Mgb, Fe5270, and Fe5335 for the whole FoV, and used them to derive Fe3 and [MgFe]’. These indices were used to derive [α/Fe]. This galaxy is dominated by old metal-rich populations (12.6 Gyr; 1.0 and 1.6 Z⊙) with a negative metallicity gradient. We also found a recent (∼63 Myr) metal-rich (1.6 Z⊙) residual star formation in the centre of the galaxy. A dust lane with a peak extinction in the V band of 0.65 mag is seen. No signs of ordered stellar motion are found and the stellar kinematics is dispersion dominated. All indices show a spatial profile varying significantly along the FoV. Mg2 shows a shallow gradient, compatible with the occurrence of mergers in the past. Mgb and Fe3 profiles suggest different enrichment processes for these elements. We observe three distinct regions: for R< 100 pc and R > 220 pc, Mg2, Mgb anticorrelate with respect to Fe3 and [MgFe]’, and for 100 pc <R< 220 pc, they correlate, hinting at different enrichment histories. The [α/Fe] profile is really complex and has a central value of ∼0.2 dex. We interpret this as the result of a past merger with another galaxy with a different [α/Fe] history, thus explaining the [α/Fe] maps.

 

Red geysers are a specific type of quiescent galaxy, denoted by twin jets emerging from their galactic centres. These bisymmetric jets possibly inject energy and heat into the surrounding material, effectively suppressing star formation by stabilizing cool gas. In order to confirm the presence and evolutionary consequences of these jets, this paper discusses the scaling, stacking, and conversion of 21-cm H i flux data sourced from the H i-MaNGA survey into H i gas-to-stellar mass (G/S) spectra. Our samples were dominated by non-detections, or galaxies with weak H i signals, and consequently by H i upper limits. The stacking technique discussed successfully resolved emission features in both the red geyser G/S spectrum and the control sample G/S spectrum. From these stacked spectra, we find that on average, red geyser galaxies have G/S of 0.086 ± 0.011 (random) + 0.029 (systematic), while non-red geyser galaxies of similar stellar mass have a G/S ratio of 0.039 ± 0.018 (random) + 0.013 (systematic). Therefore, we find no statistically significant evidence that the H i content of red geysers is different from the general quiescent population.

 

We present, for the first time, the relationship between local stellar mass surface density, Σ_*, and N/O derived from SDSS-IV MaNGA data, using a sample of 792,765 high signal-to-noise ratio star-forming spaxels. Using a combination of phenomenological modeling and partial correlation analysis, we find that Σ_*alone is insufficient to predict the N/O in MaNGA spaxels and that there is an additional dependence on the local star formation rate surface density, Σ_SFR. This effect is a factor of 3 stronger than the dependence of 12+log(O/H) on Σ_SFR. Surprisingly, we find that the local N/O scaling relations also depend on the total galaxy stellar mass at fixed Σ_*and the galaxy size at fixed stellar mass. We find that more compact galaxies are more nitrogen rich, even when Σ_*and Σ_SFRare controlled for. We show that ∼50% of the variance of N/O is explained by the total stellar mass and size. Thus, the evolution of nitrogen in galaxies is set by more than just local effects and does not simply track the buildup of oxygen in galaxies. The precise form of the N/O–O/H relation is therefore sensitive to the sample of galaxies from which it is derived. This result casts doubt on the universal applicability of nitrogen-based strong-line metallicity indicators derived in the local universe.

 

Abstract We present the active galactic nucleus (AGN) catalog and optical spectroscopy for the second data release of the Swift BAT AGN Spectroscopic Survey (BASS DR2). With this DR2 release we provide 1449 optical spectra, of which 1182 are released for the first time, for the 858 hard-X-ray-selected AGNs in the Swift BAT 70-month sample. The majority of the spectra (801/1449, 55%) are newly obtained from Very Large Telescope (VLT)/X-shooter or Palomar/Doublespec. Many of the spectra have both higher resolution ( R > 2500, N ∼ 450) and/or very wide wavelength coverage (3200–10000 Å, N ∼ 600) that are important for a variety of AGN and host galaxy studies. We include newly revised AGN counterparts for the full sample and review important issues for population studies, with 47 AGN redshifts determined for the first time and 790 black hole mass and accretion rate estimates. This release is spectroscopically complete for all AGNs (100%, 858/858), with 99.8% having redshift measurements (857/858) and 96% completion in black hole mass estimates of unbeamed AGNs (722/752). This AGN sample represents a unique census of the brightest hard-X-ray-selected AGNs in the sky, spanning many orders of magnitude in Eddington ratio ( L / L Edd = 10 −5 –100), black hole mass ( M BH = 10 5 –10 10 M ⊙ ), and AGN bolometric luminosity ( L bol = 10 40 –10 47 erg s −1 ). 

Context. The M BH – σ ⋆ relation is considered a result of coevolution between the host galaxies and their supermassive black holes. For elliptical bulge hosting inactive galaxies, this relation is well established, but there is still discussion concerning whether active galaxies follow the same relation. Aims. In this paper, we estimate black hole masses for a sample of 19 local luminous active galactic nuclei (AGNs; LLAMA) to test their location on the M BH – σ ⋆ relation. In addition, we test how robustly we can determine the stellar velocity dispersion in the presence of an AGN continuum and AGN emission lines, and as a function of signal-to-noise ratio. Methods. Supermassive black hole masses ( M BH ) were derived from the broad-line-based relations for H α , H β , and Pa β emission line profiles for Type 1 AGNs. We compared the bulge stellar velocity dispersion ( σ ⋆ ) as determined from the Ca II triplet (CaT) with the dispersion measured from the near-infrared CO (2-0) absorption features for each AGN and find them to be consistent with each other. We applied an extinction correction to the observed broad-line fluxes and we corrected the stellar velocity dispersion by an average rotation contribution as determined from spatially resolved stellar kinematic maps. Results. The H α -based black hole masses of our sample of AGNs were estimated in the range 6.34 ≤ log M BH  ≤ 7.75 M ⊙ and the σ ⋆CaT estimates range between 73 ≤  σ ⋆CaT  ≤ 227 km s −1 . From the so-constructed M BH  −  σ ⋆ relation for our Type 1 AGNs, we estimate the black hole masses for the Type 2 AGNs and the inactive galaxies in our sample. Conclusions. We find that our sample of local luminous AGNs is consistent with the M BH – σ ⋆ relation of lower luminosity AGNs and inactive galaxies, after correcting for dust extinction and the rotational contribution to the stellar velocity dispersion. 

Abstract This paper documents the seventeenth data release (DR17) from the Sloan Digital Sky Surveys; the fifth and final release from the fourth phase (SDSS-IV). DR17 contains the complete release of the Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey, which reached its goal of surveying over 10,000 nearby galaxies. The complete release of the MaNGA Stellar Library accompanies this data, providing observations of almost 30,000 stars through the MaNGA instrument during bright time. DR17 also contains the complete release of the Apache Point Observatory Galactic Evolution Experiment 2 survey that publicly releases infrared spectra of over 650,000 stars. The main sample from the Extended Baryon Oscillation Spectroscopic Survey (eBOSS), as well as the subsurvey Time Domain Spectroscopic Survey data were fully released in DR16. New single-fiber optical spectroscopy released in DR17 is from the SPectroscipic IDentification of ERosita Survey subsurvey and the eBOSS-RM program. Along with the primary data sets, DR17 includes 25 new or updated value-added catalogs. This paper concludes the release of SDSS-IV survey data. SDSS continues into its fifth phase with observations already underway for the Milky Way Mapper, Local Volume Mapper, and Black Hole Mapper surveys.