galaxies

Nuclear Activity in the Low Metallicity Dwarf Galaxy SDSS J0944-0038: A Glimpse into the Primordial Universe

First author: Michael Reefe Local low metallicity dwarf galaxies are relics of the early universe and hold clues into the origins of supermassive black holes (SMBHs). In recent work, coronal lines have been used to unveil a population of candidate accreting black holes in dwarf galaxies with gas phase metallicities and stellar masses well below the host galaxies of any previously known AGNs. Using MUSE/VLT observations, we report the detection of [Fe X] $\lambda$6374 coronal line emission and a broad H$\alpha$ line in the nucleus of SDSS J094401.

Constraints on modified gravity from the BOSS galaxy survey

First author: Lorenzo Piga We develop a pipeline to set new constraints on scale-independent modified gravity, from the galaxy power spectrum in redshift space of BOSS DR12. The latter is modelled using the effective field theory of large-scale structure up to 1-loop order in perturbation theory. We test our pipeline on synthetic and simulated data, to assess systematic biases on the inferred cosmological parameters due to marginalization and theoretical errors, and we apply it to the normal branch of the DGP model with a $\Lambda$CDM background.

Dust-free starburst galaxies at redshifts $z>10$

First author: Biman B. Nath One of the most distant galaxies GN-z11 was formed when the Universe was $\le$ 400 Myr old, and it displays a burst-like star formation rate $\sim 25~\msun$ yr$^{-1}$ with a metallicity $Z\sim 0.2\pm 0.1Z_\odot$. It resembles $z=2-3$ galaxies (at ``cosmic noon") except for the fact that the measured reddening $E(B-V)=0.01\pm 0.01$ indicates the presence of little or no dust. This marked absence of dust hints towards violent dynamical events that destroy or evacuate dust along with gas out of the galaxy on a relatively short time scale and make it transparent.

EAVN Astrometry toward the Extreme Outer Galaxy: Kinematic distance with the proper motion of G034.84-00.95

First author: Nobuyuki Sakai We aim to reveal the structure and kinematics of the Outer-Scutum-Centaurus (OSC) arm located on the far side of the Milky Way through very long baseline interferometry (VLBI) astrometry using KaVA, which is composed of KVN (Korean VLBI Network) and VERA (VLBI Exploration of Radio Astrometry). We report the proper motion of a 22 GHz H${2}$O maser source, which is associated with the star-forming region G034.

Hydrostatic Mass Profiles of Galaxy Clusters in the eROSITA Survey

First author: Dominik Scheck To assume hydrostatic equilibrium between the intracluster medium and the gravitational potential of galaxy clusters is an extensively used method to investigate their total masses. We want to test hydrostatic masses obtained with an observational code in the context of the SRG/eROSITA survey. We use the hydrostatic modeling code MBProj2 to fit surface-brightness profiles to simulated clusters with idealized properties as well as to a sample of 93 clusters taken from the Magneticum Pathfinder simulations.

MASCOT: Molecular gas depletion times and metallicity gradients -- evidence for feedback in quenching active galaxies

First author: C. Bertemes We present results from the first public data release of the MaNGA-ARO Survey of CO Targets (MASCOT), focussing our study on galaxies whose star-formation rates and stellar masses place them below the ridge of the star-forming Main Sequence. In optically-selected type 2 AGN/LINERs/Composites, we find an empirical relation between gas-phase metallicity gradients $\nabla Z$ and global molecular gas depletion times $t_\mathrm{dep} = M_{H_2}$/SFR with “more quenched” systems showing flatter/positive gradients.

Mesh-free hydrodynamics in PKDGRAV3 for galaxy formation simulations

First author: Isaac Alonso Asensio We extend the state-of-the-art N-body code PKDGRAV3 with the inclusion of mesh-free gas hydrodynamics for cosmological simulations. Two new hydrodynamic solvers have been implemented, the mesh-less finite volume and mesh-less finite mass methods. The solvers manifestly conserve mass, momentum and energy, and have been validated with a wide range of standard test simulations, including cosmological simulations. We also describe improvements to PKDGRAV3 that have been implemented for performing hydrodynamic simulations.

The production of ionizing photons in UV-faint z~3-7 galaxies

First author: Gonzalo Prieto-Lyon The demographics of the production and escape of ionizing photons from UV-faint early galaxies is a key unknown in discovering the primary drivers of reionization. With the advent of JWST it is finally possible to observe the rest-frame optical nebular emission from individual sub-L$^*$ z>3 galaxies to measure the production of ionizing photons, $\xi_\mathrm{ion}$. Here we study a sample of 380 z~3-7 galaxies spanning -23 <M$\mathrm{UV}$ < -15.

The spatially resolved view of star formation in galaxy clusters

First author: Bianca M. Poggianti Integral field spectroscopic studies of galaxies in dense environments, such as clusters and groups of galaxies, have provided new insights for understanding how star formation proceeds, and quenches. I present the spatially resolved view of the star formation activity and its link with the multiphase gas in cluster galaxies based on MUSE and multi-wavelength data of the GASP survey. I discuss the link among the different scales (i.

Witnessing a Galaxy Cluster Merger with JWST and a Chandra X-ray Temperature Map

First author: Brian C. Alden The first James Webb Space Telescope (JWST) image released was of galaxy cluster SMACSJ0723.3- 7327, a lensing cluster at z=0.39 showing detail only JWST can provide. While the majority of the focus has been on the brilliantly lensed galaxies at redshifts far beyond it, there is more to the story than it being just a lensing cluster. The Chandra X-ray temperature map tells a tale of a merging cluster with a significant subcluster leaving a wake in the intracluster medium (ICM).