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: Yang-Ji Li
We report on the identification of a new $\gamma$-ray emitting narrow-line Seyfert 1 galaxy ($\gamma$-NLS1), SDSS J095909.51+460014.3 (hereinafter J0959+4600, $z$ = 0.399), by establishing its association with a $\gamma$-ray source 4FGL 0959.6+4606, although its low-energy counterpart was suggested to be a radio galaxy 2MASX J09591976+4603515 (hereinafter J0959+4603). \emph{WISE} long-term light curves of these two sources reveal diverse infrared variability patterns. Violent infrared variations of J0959+4600 with an amplitude up to one order of magnitude has been detected, while variability is mild for the other one.
First author: Liang Li
Gamma-ray bursts (GRBs) are the most powerful explosions in the universe. The standard model invokes a relativistic fireball with a bright photosphere emission component. How efficiently the jet converts its energy to radiation is a long-standing problem and it is poorly constrained. A definitive diagnosis of GRB radiation components and measurement of GRB radiative efficiency requires prompt emission and afterglow data with high-resolution and wide-band coverage in time and energy.
