galaxies

Formation of star clusters and enrichment by massive stars in simulations of low-metallicity galaxies with a fully sampled initial stellar mass function

First author: Natalia Lahén We present new GRIFFIN project hydrodynamical simulations that model the formation of galactic star cluster populations in low-metallicity ($Z=0.00021$) dwarf galaxies, including radiation, supernova and stellar wind feedback of individual massive stars. In the simulations, stars are sampled from the stellar initial mass function (IMF) down to the hydrogen burning limit of 0.08 M$_\odot$. Mass conservation is enforced within a radius of 1 pc for the formation massive stars.

The Pristine Inner Galaxy Survey (PIGS) VI: Different vertical distributions between two DIBs at 442.8 nm and 862.1 nm

First author: He Zhao Although diffuse interstellar bands (DIBs) were discovered over 100 years ago, for most of them, their origins are still unknown. Investigation on the correlations between different DIBs is an important way to study the behavior and distributions of their carriers. Based on stacking thousands of spectra from the Pristine Inner Galaxy Survey, we study the correlations between two DIBs at 442.8 nm ($\lambda$442.8) and 862.1 nm ($\lambda$862.

VINTERGATAN-GM: The cosmological imprints of early mergers on Milky-Way-mass galaxies

First author: Martin P. Rey We present a new suite of cosmological zoom-in hydrodynamical ($\approx 20, \mathrm{pc}$) simulations of Milky-Way mass galaxies to study how a varying mass ratio for a Gaia-Sausage-Enceladus (GSE) progenitor impacts the $z=0$ chemodynamics of halo stars. Using the genetic modification approach, we create five cosmological histories for a Milky-Way-mass dark matter halo ($M_{200} \approx 10^{12} , M_\mathrm{\odot}$), incrementally increasing the stellar mass ratio of a $z\approx2$ merger from 1:25 to 1:2, while fixing the galaxy’s final dynamical, stellar mass and large-scale environment.

WALLABY Pilot Survey: HI gas kinematics of galaxy pairs in cluster environment

First author: Shin-Jeong Kim We examine the HI gas kinematics of galaxy pairs in two clusters and a group using Australian Square Kilometre Array Pathfinder (ASKAP) WALLABY pilot survey observations. We compare the HI properties of galaxy pair candidates in the Hydra I and Norma clusters, and the NGC 4636 group, with those of non-paired control galaxies selected in the same fields. We perform HI profile decomposition of the sample galaxies using a tool, {\sc baygaud} which allows us to de-blend a line-of-sight velocity profile with an optimal number of Gaussian components.

Infrared Properties of OGLE4 Mira variables in our Galaxy

First author: Kyung-Won Suh We investigate infrared properties of OGLE4 Mira variables in our Galaxy. For each object, we cross-identify the WISE, 2MASS, and IRAS counterparts. We present various IR two-color diagrams (2CDs) and period-magnitude and period-color relations for the Mira variables. Generally, the Miras variables with longer periods are brighter in the IR fluxes and redder in the IR colors. In this work, we also revise and update the previous catalog of AGB stars in our Galaxy using the new sample of OGLE4 Mira variables.

Euclid preparation. XXVII. Covariance model validation for the 2-point correlation function of galaxy clusters

First author: Euclid Collaboration Aims. We validate a semi-analytical model for the covariance of real-space 2-point correlation function of galaxy clusters. Methods. Using 1000 PINOCCHIO light cones mimicking the expected Euclid sample of galaxy clusters, we calibrate a simple model to accurately describe the clustering covariance. Then, we use such a model to quantify the likelihood analysis response to variations of the covariance, and investigate the impact of a cosmology-dependent matrix at the level of statistics expected for the Euclid survey of galaxy clusters.

FOREVER22: the first bright galaxies with population III stars at redshifts $z \simeq 10-20$ and comparisons with JWST data

First author: Hidenobu Yajima We study the formation of the first galaxies in overdense regions modelled by the FOREVER22 simulation project. Our simulations successfully reproduce the star formation rates and the $M_{\rm UV}-M_{\rm star}$ relations of candidate galaxies at $z \sim 10-14$ observed by James Webb Space Telescope (JWST). We suggest that the observed galaxies are hosted by dark-matter haloes with $M_{\rm h} \sim 10^{11}~\rm M_{\odot}$ and are in short-period starburst phases.

Galaxy and Mass Assembly (GAMA): Extended Intra-Group Light in a group at $z=0.2$ from deep Hyper-Suprime Cam images

First author: Cristina Martinez-Lombilla We present a pilot study to assess the potential of Hyper Suprime-Cam Public Data Release 2 (HSC-PDR2) images for the analysis of extended faint structures within groups of galaxies. We examine the intra-group light (IGL) of the group 400138 ($M_{\rm{dyn}}= 1.3 \pm 0.5 \times 10^{13} $M${\odot}$, $z\sim 0.2$) from the Galaxy And Mass Assembly (GAMA) survey using Hyper-Suprime Cam Subaru Strategic Program Public Data Release 2 (HSC-PDR2) images in $g$, $r$, and $i$ bands.

Identifying and Characterizing the Most Heavily Dust-Obscured Galaxies at $1 \le z \le 4$

First author: Nicholas S. Martis We present 65 extremely dust-obscured galaxies from the UltraVISTA DR3 survey of the COSMOS field at $1<z<4$. In contrast to other studies of dusty galaxies, we select our sample based on dust attenuation measured by UV-MIR spectral energy distribution (SED) modeling that allows for extreme attenuation levels. We construct our sample by making cuts at $1 \le z \le 4$, A$V \ge 3$, and log(M$*$/M$_\odot$)$ \ge 10.

iMaNGA: mock MaNGA galaxies based on IllustrisTNG-50 and MaStar SSPs. II. the catalogue

First author: Lorenza Nanni To probe the current theory on galaxy formation and evolution, an increased synergy between observations and simulations is necessary. For this reason, in our previous paper of this series, we presented a method to mock SDSS-IV/MaNGA integral-field spectroscopic galaxy observations from cosmological simulations of galaxy formation. Here we present the resulting mock galaxy catalogue. This catalogue consists of 1,000 unique galaxies in IllustrisTNG-50 falling into the SDSS-IV/MaNGA-primary target footprint, defined in the redshift and i-band absolute magnitude space.