星系天体物理

This work presents the first dedicated optical--mid-infrared time-domain variability and dust-reverberation analysis of the isolated NLSy1 galaxies Mrk 42 and Mrk 493. We combine ZTF optical light curves, WISE mid-infrared monitoring,…

We present Very Large Telescope/Xshooter spectrophotometric observations of eleven low-redshift (z<0.085) compact star-forming galaxies (`high O32 sample'). These galaxies are characterised by extremely high emission-line ratios…

We develop a model-independent framework to quantify phase-space "crystallization", the degree of ordered radial and kinematic substructure, in 79 Galactic globular clusters using the Gaia EDR3-based membership catalogue of E. Vasiliev & H.…

We investigate the physical origin of kinematically persistent planes (KPPs) of satellite galaxies in a sample of 190 Milky Way (MW)/M31-like host-satellite systems drawn from the TNG50 simulation. Building on the identification of 46 early…

Large spectroscopic and astrometric surveys have revealed complex wave-like features in the Milky Way disk, suggesting that its kinematic and chemical structures are shaped by time-dependent perturbations. Recent studies have reported…

We present the first results from a program searching for extended Ly$\alpha$ halos around high redshift ($ z \gtrsim 6.5$) quasars using the red channel of the Keck Cosmic Web Imager (KCWI). Our observations reveal a Ly$\alpha$ halo…

We present spatially resolved Keck/LRIS spectroscopy of three clumpy star-forming galaxies at $z\sim0.1$, comparing outflow properties traced by H$\alpha$ and Mg II emission with those probed by Mg II and Na I D absorption. Outflow…

The extremely metal-poor nature of the C-19 stream indicates that its progenitor was a primordial stellar system born in the very early Universe. Current observations show that it has a small metallicity dispersion (0.18 at the 95%…

We analyzed the distribution of spin parity in spiral galaxies using the HSC DR2 data. The spiral winding parity of disk galaxies, observed as S-spiral or Z-spiral projected onto the sky plane, provides robust information on the sign of the…

We present sensitive ($\sim$9 $\mu$Jy), sub-arcsecond resolution radio continuum observations at 9.0 GHz (3.3 cm) and 14.0 GHz (2.1 cm) obtained with the Karl G. Jansky Very Large Array (VLA) toward the nearby Coronet Cluster in Corona…

We investigate the mass-metallicity relation (MZR) from z=1 to z=9 using electron-temperature-based gas-phase metallicities and examine how auroral-line selection, star-formation history, and secondary abundances affect its interpretation…

Molecular clouds form stars from the interstellar medium via gravitational collapse, following a sequence from low-density gas to high-density cores and eventually the formation of stars. In classical density wave theory, gas clouds…

We analyze the spectra of the central nuclei of extremely red quasars (ERQs) observed as part of the JWST ERS Q3D program. We focus on the complex kinematic structures of the prominent rest-frame optical emission lines. Our modeling allows…

We present the GASKAP-HI pilot absorption survey of neutral hydrogen (HI) in the Magellanic system. This survey provides 3219 sightlines across the Large (LMC) and Small Magellanic Clouds (SMC) and the Magellanic Bridge (MB) towards 1.4-GHz…

We present new James Webb Space Telescope Mid-Infrared Instrument (MIRI) Medium-Resolution Spectrometer (MRS) observations of the nearby ultra-luminous infrared galaxy F10565+2448. These integral field spectroscopic data reveal an…

The circumgalactic medium (CGM) is known to contain multiphase gas in various stages of evolution and interaction with the galaxy. In order to characterize its detailed behavior on short timescales, we use a subregion of the TNG100…

The approximately flat outer parts of spiral galaxy rotation curves are commonly interpreted as evidence for a discrepancy between the observed baryonic mass and the dynamical mass inferred from the measured orbital velocities. In many…

We identify different dust features in our compilation of infrared spectra for 267 planetary nebulae (PNe) from the Spitzer, ISO, and IRAS telescopes. We classify 209 objects according to their dust type: mixed dust (MD), oxygen-rich dust…

We present a neural network classification (NNC) method for photometric redshift estimation that produces well-calibrated redshift probability density functions (PDFs). The method discretizes the redshift space into ordered bins and…

The James Webb Space Telescope (JWST) has revealed an unexpected excess of UV-bright galaxies at z>10, unaccounted for by extrapolations from pre-JWST observations and theoretical models. Understanding the physical properties and star…