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1. The cold dust content of the nearby galaxies IC 5325, NGC 7496, NGC 7590, and NGC 7599

   https://doi.org/10.1093/mnras/stab1048  

   Singh, Swapnil; Ashby, M L; Vig, Sarita; Ghosh, S K; Jarrett, T; Crawford, T M; Malkan, Matthew A; Archipley, M; Vieira, J D (May 2021, Monthly Notices of the Royal Astronomical Society)

   null (Ed.)

   ABSTRACT Star-forming galaxies are rich reservoirs of dust, both warm and cold. But the cold dust emission is faint alongside the relatively bright and ubiquitous warm dust emission. Recently, evidence for a very cold dust (VCD) component has also been revealed via millimetre/submillimetre (mm/sub-mm) photometry of some galaxies. This component, despite being the most massive of the three dust components in star-forming galaxies, is by virtue of its very low temperature, faint and hard to detect together with the relatively bright emission from warmer dust. Here, we analyse the dust content of a carefully selected sample of four galaxies detected by IRAS, WISE, and South Pole Telescope (SPT), whose spectral energy distributions (SEDs) were modelled to constrain their potential cold dust content. Low-frequency radio observations using the Giant Metrewave Radio Telescope (GMRT) were carried out to segregate cold dust emission from non-thermal emission in mm/sub-mm wavebands. We also carried out AstroSat/Ultraviolet Imaging Telescope (UVIT) observations for some galaxies to constrain their SED at shorter wavelengths so as to enforce energy balance for the SED modelling. We constructed their SEDs across a vast wavelength range (extending from UV to radio frequencies) by assembling global photometry from GALEX FUV + NUV, UVIT, Johnson BRI, 2MASS, WISE, IRAC, IRAS, AKARI, ISO PHOT, Planck HFI, SPT, and GMRT. The SEDs were modelled with cigale to estimate their basic properties, in particular to constrain the masses of their total and VCD components. Although the galaxies’ dust masses are dominated by warmer dust, there are hints of VCD in two of the targets, NGC 7496 and NGC 7590. 

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2. Monitoring AGN with Hβ Asymmetry: NGC 2617 and NGC 4151

   Olson, K.; Adelman, C.; Carter, Z.; Murphree, A.; Oeur, M.; Roth, T.; Schonsberg, S.; Zastrocky, T.; Dong-Wei, B.; Zhao, B.; et al (January 2020, Bulletin of the American Astronomical Society)
3. Neutral atomic and molecular gas dynamics in the nearby spiral galaxies NGC 1512, NGC 4535, and NGC 7496

   https://doi.org/10.1051/0004-6361/202450265  

   Laudage, Sebastian; Eibensteiner, Cosima; Bigiel, Frank; Leroy, Adam K; Meidt, Sharon; Schinnerer, Eva; de_Blok, W_J G; Querejeta, Miguele; Stuber, Sophia; Colombo, Dario; et al (October 2024, Astronomy & Astrophysics)

   Neutral atomic gas (H I) effectively traces galactic dynamics across mid to large galactocentric radii. However, its limitations in observing small-scale changes within the central few kiloparsecs, coupled with the often observed H Ideficit in galactic centers, necessitates the use of molecular gas emission as a preferred tracer in these regions. Understanding the dynamics of both neutral atomic and molecular gas is crucial for a more complete understanding of how galaxies evolve, funnel gas from the outer disk into their central parts, and eventually form stars. In this work we aim to quantify the dynamics of both, the neutral atomic and molecular gas, in the nearby spiral galaxies NGC 1512, NGC 4535, and NGC 7496 using new MeerKAT H Iobservations together with ALMA CO (2-1) observations from the PHANGS collaboration. We use the analysis tool^3DBarolo to fit tilted ring models to the H Iand CO observations. A combined approach of using the H Ito constrain the true disk orientation parameters before applying these to the CO datasets is tested. This paper sets expectations for the results of the upcoming high-resolution H Icoverage of many galaxies in the PHANGS-ALMA sample using MeerKAT or VLA, to establish a robust methodology for characterizing galaxy orientations and deriving dynamics from combing new H Iwith existing CO data. 

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4. Stellar graveyards: clustering of compact objects in globular clusters NGC 3201 and NGC 6397

   https://doi.org/10.1093/mnras/stac1337  

   Vitral, Eduardo; Kremer, Kyle; Libralato, Mattia; Mamon, Gary A.; Bellini, Andrea (June 2022, Monthly Notices of the Royal Astronomical Society)

   ABSTRACT We analyse Gaia EDR3 and re-calibrated HST proper motion data from the core-collapsed and non-core-collapsed globular clusters NGC 6397 and NGC 3201, respectively, with the Bayesian mass-orbit modelling code MAMPOSSt-PM. We use Bayesian evidence and realistic mock data sets constructed with Agama to select between different mass models. In both clusters, the velocities are consistent with isotropy within the extent of our data. We robustly detect a dark central mass (DCM) of roughly $$1000\, \rm M_\odot$$ in both clusters. Our MAMPOSSt-PM fits strongly prefer an extended DCM in NGC 6397, while only presenting a mild preference for it in NGC 3201, with respective sizes of a roughly one and a few per cent of the cluster effective radius. We explore the astrophysics behind our results with the CMC Monte Carlo N-body code, whose snapshots best matching the phase space observations lead to similar values for the mass and size of the DCM. The internal kinematics are thus consistent with a population of hundreds of massive white dwarfs in NGC 6397, and roughly 100 segregated stellar-mass black holes in NGC 3201, as previously found with CMC. Such analyses confirm the accuracy of both mass-orbit modelling and Monte Carlo N-body techniques, which together provide more robust predictions on the DCM of globular clusters (core-collapsed or not). This opens possibilities to understand a vast range of interesting astrophysical phenomena in clusters, such as fast radio bursts, compact object mergers, and gravitational waves. 

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5. Pa β , H α , and Attenuation in NGC 5194 and NGC 6946

   https://doi.org/10.3847/1538-4357/ab77a8  

   Kessler, Sarah; Leroy, Adam; Querejeta, Miguel; Murphy, Eric; Rebolledo, David; Sandstrom, Karin; Schinnerer, Eva; Wong, Tony (March 2020, The Astrophysical Journal)