galaxies

First author: Yufei Zhang We study the potential of the galaxy cluster sample expected from the China Space Station Telescope (CSST) survey to constrain dark energy properties. By modelling the distribution of observed cluster mass for a given true mass to be log-normal and adopting a selection threshold in the observed mass $M_{200m} \geq 0.836 \times 10^{14} h^{-1}M_{\odot}$, we find about $4.1 \times 10^{5}$ clusters in the redshift range $0 \leq z \leq 1.

First author: S. Radinović We investigate the cosmological constraints that can be expected from measurement of the cross-correlation of galaxies with cosmic voids identified in the Euclid spectroscopic survey, which will include spectroscopic information for tens of millions of galaxies over $15,000$ deg$^2$ of the sky in the redshift range $0.9\leq z<1.8$. We do this using simulated measurements obtained from the Flagship mock catalogue, the official Euclid mock that closely matches the expected properties of the spectroscopic data set.

First author: Tobias Géron We study the bar pattern speeds and corotation radii of 225 barred galaxies, using IFU data from MaNGA and the Tremaine-Weinberg method. Our sample, which is divided between strongly and weakly barred galaxies identified via Galaxy Zoo, is the largest that this method has been applied to. We find lower pattern speeds for strongly barred galaxies than for weakly barred galaxies. As simulations show that the pattern speed decreases as the bar exchanges angular momentum with its host, these results suggest that strong bars are more evolved than weak bars.

First author: G. Castignani Brightest cluster galaxies (BCGs) are among the most massive galaxies in the Universe. Their star formation (SF) history and stellar mass assembly are debated. Recent studies suggest the presence of an emerging population of intermediate-$z$ star forming and gas-rich BCGs, where the molecular gas reservoirs are impacted by strong environmental processing. We have selected three among the most star-forming $z\sim0.4$ BCGs in the Kilo-Degree Survey (KiDS), and observed them with the IRAM 30m telescope in the first three CO transitions.

First author: Alexa C. Gordon We present a comprehensive catalog of observations and stellar population properties for 23 highly secure host galaxies of fast radio bursts (FRBs). Our sample comprises six repeating FRBs and 17 apparent non-repeaters. We present 82 new photometric and eight new spectroscopic observations of these hosts. Using stellar population synthesis modeling and employing non-parametric star formation histories (SFHs), we find that FRB hosts have a median stellar mass of $\approx 10^{9.

First author: Madeline A. Marshall Integral Field Spectroscopy (IFS) with JWST NIRSpec will significantly improve our understanding of the first quasars, by providing spatially resolved, infrared spectroscopic capabilities which cover key rest-frame optical emission lines that have been previously unobservable. Here we present our results from the first two z>6 quasars observed as a part of the NIRSpec Galaxy Assembly IFS GTO program, DELS J0411-0907 at z=6.82 and VDES J0020-3653 at z=6.

First author: Mikhail M. Ivanov We present a framework for self-consistent cosmological analyses of the full-shape anisotropic bispectrum, including the quadrupole $(\ell=2)$ and hexadecapole $(\ell=4)$ moments. This features a novel window-free algorithm for extracting the latter quantities from data, derived using a maximum-likelihood prescription. Furthermore, we introduce a theoretical model for the bispectrum multipoles (which does not introduce new free parameters), and test both aspects of the pipeline on several high-fidelity mocks, including the PT Challenge suite of gigantic cumulative volume.

First author: Corey Brummel-Smith Early photometric results from JWST have revealed a number of galaxy candidates above redshift 10. The initial estimates of inferred stellar masses and the associated cosmic star formation rates are above most theoretical model predictions up to a factor of 20 in the most extreme cases, while this has been moderated after the recalibration of NIRCam and subsequent spectroscopic detections. Using these recent JWST observations, we use galaxy scaling relations from cosmological simulations to model the star formation history to very high redshifts, back to a starting halo mass of 10^7 solar masses, to infer the intrinsic properties of the JWST galaxies.

First author: Wei Du With mock strong gravitational lensing images, we investigate the performance of broken power-law (BPL) model on the mass reconstruction of galaxy-scale lenses. An end-to-end test is carried out, including the creation of mock strong lensing images, the subtraction of lens light, and the reconstruction of lensed images. Based on these analyses, we can reliably evaluate how accurate the lens mass and source light distributions can be measured.

First author: Gourab Giri We search for signatures of recent galaxy close interactions and mergers in a sample of 202 early-type galaxies in the local universe from the public SDSS Stripe82 deep images ($\mu_r \sim 28.5$ mag arcsec$^{-2}$). Using two different methods to remove galaxies’ smooth and symmetric light distribution, we identify and characterize eleven distinct types of merger remnants embedded in the diffuse light of these early-type galaxies. We discuss how the morphology of merger remnants can result from different kinds of minor and major mergers, and estimate the fraction of early-type galaxies in the local universe with evidence of recent major (27%) and minor (57%) mergers.