galaxies

The interconnection between galaxy mergers, AGN activity and rapid quenching of star formation in simulated post-merger galaxies

First author: Salvatore Quai We investigate the role of galaxy mergers on supermassive black hole (SMBH) accretion and star formation quenching in three state-of-the-art cosmological simulations with contrasting physics models: EAGLE, Illustris and IllustrisTNG. We find that recently coalesced ‘post-mergers’ in all three simulations have elevated SMBH accretion rates by factors of ~2-5. However, rapid (within 500 Myr of coalescence) quenching of star formation is rare, with incidence rates of 0.

Using Machine Learning to Determine Morphologies of $z<1$ AGN Host Galaxies in the Hyper Suprime-Cam Wide Survey

First author: Chuan Tian We present a machine-learning framework to accurately characterize morphologies of Active Galactic Nucleus (AGN) host galaxies within $z<1$. We first use PSFGAN to decouple host galaxy light from the central point source, then we invoke the Galaxy Morphology Network (GaMorNet) to estimate whether the host galaxy is disk-dominated, bulge-dominated, or indeterminate. Using optical images from five bands of the HSC Wide Survey, we build models independently in three redshift bins: low $(0<z<0.

Anisotropic correlation functions as tracers of central galaxy alignments in simulations

First author: Facundo Rodriguez Motivated by observational results, we use hydrodynamical numerical simulations to study the alignment of the central galaxies in groups with the surrounding structures. This approach allows us to analyse galaxy and group properties not available in observations. To perform this analysis, we use a modified version of the two-point cross-correlation function and a measure of the angle between the semi-major axes of the central galaxies and the larger structures.

CALSAGOS: Clustering ALgorithmS Applied to Galaxies in Overdense Systems

First author: D. E. Olave-Rojas In this paper we present CALSAGOS: Clustering ALgorithmS Applied to Galaxies in Overdense Systems which is a PYTHON package developed to select cluster members and to search, find, and identify substructures. CALSAGOS is based on clustering algorithms and was developed to be used in spectroscopic and photometric samples. To test the performance of CALSAGOS we use the S-PLUS’s mock catalogues and we found an error of 1% - 6% on member selection depending on the function that is used.

CI and CO in Nearby Spiral Galaxies -- I. Line Ratio and Abundance Variations at ~ 200 pc Scales

First author: Daizhong Liu We present new neutral atomic carbon $[CI]$(3P1-3P0) mapping observations within the inner ~7 kpc and ~4 kpc of the disks of NGC3627 and NGC4321 at a spatial resolution of 190 pc and 270 pc, respectively, using the ALMA Atacama Compact Array (ACA). We combine these with the CO(2-1) data from PHANGS-ALMA, and literature $[CI]$ and CO data for two other starburst and/or active galactic nucleus (AGN) galaxies (NGC1808, NGC7469), to study: a) the spatial distributions of CI and CO emission; b) the observed line ratio RCICO = I_$[CI]$(1-0)/I_CO(2-1) as a function of various galactic properties; and c) the abundance ratio of $[CI/CO]$.

Comparing the Locations of Supernovae to CO (2-1) Emission in their Host Galaxies

First author: Ness Mayker Chen We measure the molecular gas environment near recent ($< 100$ yr old) supernovae (SNe) using $\sim1’’$ or $\leq 150$pc resolution CO (2-1) maps from the PHANGS-ALMA survey of nearby star-forming galaxies. This is arguably the first such study to approach the scales of individual massive molecular clouds ($M_{\rm mol} \gtrsim 10^{5.3}$ M$_{\odot}$). Using the Open Supernova Catalog (OSC), we identify 63 SNe within the PHANGS-ALMA footprint.

Gas metallicity distributions in SDSS-IV MaNGA galaxies: what drives gradients and local trends?

First author: Nicholas Fraser Boardman The gas metallicity distributions across individual galaxies and across galaxy samples can teach us much about how galaxies evolve. Massive galaxies typically possess negative metallicity gradients, and mass and metallicity are tightly correlated on local scales over wide range of galaxy masses; however, the precise origins of such trends remain elusive. Here, we employ data from SDSS-IV MaNGA to explore how gas metallicity depends on local stellar mass density and on galactocentric radius within individual galaxies.

JWST's PEARLS: TN J1338$-$1942 -- I. Extreme jet triggered star-formation in a $z=4.11$ luminous radio galaxy

First author: Kenneth J. Duncan We present the first JWST observations of the $z=4.11$ luminous radio galaxy TN J1338$-$1942, obtained as part of the “Prime Extragalactic Areas for Reionization and Lensing Science” (PEARLS) project. Our NIRCam observations, designed to probe the key rest-frame optical continuum and emission line features at this redshift, enable resolved spectral energy distribution modelling that incorporates both a range of stellar population assumptions and radiative shock models.

Kinematics of the diffuse intragroup and intracluster light in groups and clusters of galaxies in the Local Universe within 100 Mpc distance

First author: Magda Arnaboldi Nearly all intragroup (IGL) and intracluster light (ICL) comes from stars that are not bound to any single galaxy but were formed in galaxies and later unbound from them. In this review we focus on the physical properties - phase space properties, metallicity and age distribution - of the ICL and IGL components of the groups and clusters in the local universe, within 100 Mpc distance.

Massive galaxy formation caught in action at z~5 with JWST

First author: Shuowen Jin We report the discovery of a compact group of galaxies, CGG-z5, at z~5.2 in the EGS field covered by the JWST/CEERS survey. CGG-z5 was selected as the highest overdensity of galaxies at z>2 in recent JWST public surveys and consists of six candidate members lying within a projected area of 1.5’‘x3’’ (10x20 kpc$^2$). All group members are HST/F435W and HST/F606W dropouts while securely detected in the JWST/NIRCam bands, yielding a narrow range of robust photometric redshifts 5.