First author: Rieko Momose
We study the environmental effect of galaxy evolution as a function of the underlying 3D dark matter density for the first time at $z=2-2.5$, in which the underlying matter density is reconstructed from galaxy and Ly$\alpha$ forest spectroscopy through dynamical forward modeling techniques. Utilizing these maps, we investigate the dependence of the star formation activities and galaxy types (mergers, submillimeter galaxies, active galactic nuclei, and quiescent galaxies) on the matter overdensity $\Delta$ and stellar mass.
First author: Alessandra De Rosa
We present a study of optically selected dual AGN with projected separations of 3–97~kpc. Using multi-wavelength (MWL) information (optical, X-rays, mid-IR), we characterized the intrinsic nuclear properties of this sample and compared them with those of isolated systems. Among the 124 X-ray detected AGN candidates, 52 appear in pairs and 72 as single X-ray sources. Through MWL analysis, we confirmed the presence of the AGN in a fraction >80% of the detected targets in pairs (42 over 52).
First author: Nikita Lovyagin
The James Webb Space Telescope (JWST), which has recently become operational, is capable of detecting objects at record-breaking redshifts, $z \gtrsim 15$. This is a crucial advance for observational cosmology, as at these redshifts the differences between alternative cosmological models manifest themselves in the most obvious way. In recent years, some observational hints have emerged indicating that the Standard Cosmological Model could require correcting. One of these hints is related to the discovery of remote galaxies whose redshifts correspond to the very young Universe (less than one billion years after the Big Bang) but which are similar to nearby galaxies.
First author: Yesukhei Jagvaral
The future astronomical imaging surveys are set to provide precise constraints on cosmological parameters, such as dark energy. However, production of synthetic data for these surveys, to test and validate analysis methods, suffers from a very high computational cost. In particular, generating mock galaxy catalogs at sufficiently large volume and high resolution will soon become computationally unreachable. In this paper, we address this problem with a Deep Generative Model to create robust mock galaxy catalogs that may be used to test and develop the analysis pipelines of future weak lensing surveys.
First author: Yesukhei Jagvaral
Upcoming cosmological weak lensing surveys are expected to constrain cosmological parameters with unprecedented precision. In preparation for these surveys, large simulations with realistic galaxy populations are required to test and validate analysis pipelines. However, these simulations are computationally very costly – and at the volumes and resolutions demanded by upcoming cosmological surveys, they are computationally infeasible. Here, we propose a Deep Generative Modeling approach to address the specific problem of emulating realistic 3D galaxy orientations in synthetic catalogs.
First author: R. N. Markwick
Supersonic interacting flows occurring in phenomena such as protostellar jets give rise to strong shocks, and have been demonstrated in several laboratory experiments. To study such colliding flows, we use the AstroBEAR AMR code to conduct hydrodynamic simulations in three dimensions. We introduce variations in the flow parameters of density, velocity, and cross sectional radius of the colliding flows %radius in order to study the propagation and conical shape of the bow shock formed by collisions between two, not necessarily symmetric, hypersonic flows.
First author: Yuanyuan Zhang
The splashback radius of a dark matter halo, which corresponds to the first apocenter radius reached by infalling matter and substructures, has been detected around galaxy clusters using a multitude of observational methods, including weak lensing measurements. In this manuscript, we present how the splashback feature in the halo density profile affects galaxy cluster masses derived through weak lensing measurements if it is not accounted for.
First author: C. Obasi
Context. The globular cluster (GC) system of Circinus galaxy has not been probed previously partly because of the location of the galaxy at - 3.8$^\circ$ Galactic latitude which suffers severely from interstellar extinction, stellar crowding, and Galactic foreground contamination. However, the deep near-infrared (NIR) photometry by the VISTA Variables in the Via L'actea Extended Survey (VVVX) in combination with the precise astrometry of Gaia EDR3 allow us to map GCs in this region.
First author: Shivani Bhandari
We present the discovery of as-of-yet non-repeating Fast Radio Burst (FRB) with the Australian Square Kilometer Array Pathfinder (ASKAP) as a part of the Commensal Real-time ASKAP Fast Transients (CRAFT) Survey. FRB 20210117A was detected at the center frequency of 1271.5 MHz with a dispersion measure (DM) of $728.95\pm 0.01$ pc cm$^{-3}$. The sub-arcsecond localization of the burst led to the identification of its host galaxy at a $z=0.
First author: Andrey Vayner
We present Keck Cosmic Web Imager (KCWI) integral field spectroscopy (IFS) observations of rest-frame UV emission lines $\rm Ly\alpha$, C IV $\lambda \lambda$ 1548 \AA, 1550\AA and He II 1640 \AA observed in the circumgalactic medium (CGM) of two $z=2$ radio-loud quasar host galaxies. We detect extended emission on 80-90 kpc scale in $\rm Ly\alpha$ in both systems with C IV, and He II emission also detected out to 30-50 kpc.
