High-resolution observations of ionized and molecular gas in the nuclear regions of galaxies are indispensable for delineating the interplay of star formation, gaseous inflows, stellar radiation, and feedback processes. Combining our new Atacama Large Millimeter/submillimeter Array band 3 mapping and archival Very Large Telescope/MUSE data, we present a spatially resolved analysis of molecular and ionized gas in the central 5.4 kpc region of NGC 1365. We find the star formation rate/efficiency (SFR/SFE) in the inner circumnuclear ring is about 0.4/1.1 dex higher than in the outer regions. At a linear resolution of 180 pc, we obtain a superlinear Kennicutt–Schmidt law, demonstrating a steeper slope (1.96 ± 0.14) than previous results presumably based on lower-resolution observations. Compared to the northeastern counterpart, the southwestern dust lane shows lower SFE, but denser molecular gas and larger virial parameters. This is consistent with an interpretation of negative feedback from an active galactic nucleus (AGN) and/or starburst, in the sense that the radiation/winds can heat and interact with the molecular gas even in relatively dense regions. After subtracting the circular motion component of the molecular gas and the stellar rotation, we detect two prominent noncircular motion components of molecular and ionized hydrogen gas, reaching a line-of-sight velocity of up to 100 km s−1. We conclude that the winds or shocked gas from the central AGN may expel the low-density molecular gas and diffuse ionized gas on the surface of the rotating disk.
We select 456 galaxies with kinematically misaligned gas and stellar components from 9546 parent galaxies in MaNGA, and classify them into 72 star-forming galaxies, 142 green-valley galaxies and 242 quiescent galaxies. Comparing the spatial resolved properties of the misaligned galaxies with control samples closely match in the Dn4000 and stellar velocity dispersion, we find that: (1) the misaligned galaxies have lower values in Vgas/σgas and Vstar/σstar (the ratio between ordered to random motion of gas and stellar components) across the entire galaxies than their control samples; (2) the star-forming and green-valley misaligned galaxies have enhanced central concentrated star formation than their control galaxies. The difference in stellar population between quiescent misaligned galaxies and control samples is small; (3) gas-phase metallicity of the green valley and quiescent misaligned galaxies are lower than the control samples. For the star forming misaligned galaxies, the difference in metallicity between the misaligned galaxies and their control samples strongly depends on how we select the control samples. All these observational results suggest external gas accretion influences the evolution of star forming and green valley galaxies, not only in kinematics/morphologies, but also in stellar populations. However, the quiescent misaligned galaxies have survived from different formation mechanisms.
In this Letter, properties of black hole (BH) mass are well checked for the interesting object SDSS J0159, a changing-look AGN and also a host galaxy of a tidal disruption event (TDE). Through spectral absorption features, the stellar velocity dispersion of SDSS J0159 can be well measured as σ ∼ 81 km/s, leading to SDSS J0159 being an apparent outlier in the M BH − σ space, because of the BH mass estimated through the M BH − σ relation about two magnitudes lower than the reported virial BH mass of about 10 8 M ⊙ . After considerations of contributions of stellar debris from the central TDE to broad line emission clouds, the over-estimated virial BH mass could be well explained in SDSS J0159. Therefore, over-estimated virial BH masses through broad line properties in the M BH − σ space could be treated as interesting clues to support central TDEs.
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