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2023.12.18

Probing Parity with Galaxy Distributions and Beyond

<p>Galaxies&#39; four-point correlation functions provide insights into parity symmetry at cosmological scales. In this talk, I will present our data analysis on the BOSS galaxy sample with a focus on various observational effects. I will also discuss some future aspects of extending the analysis, including models and connection with other observables. In addition, I will also discuss an alternative i...</p>

2023.12.18

Electromagnetic fireworks from erupting magnetars

<p>Highly magnetized neutron stars are a source of extreme transients observed in different bands, like the fast radio burst (FRB) and associated hard X-ray burst from the Galactic magnetar SGR 1935+2154. The origin of such outbursts, hard X-rays on the one hand and millisecond duration FRBs on the other hand, is still unknown. We present a global model for various kinds of such magnetar outbursti...</p>

2023.11.27

Multi-Messenger Probes on Dark Matter Beyond WIMPs

<p>We will discuss two promising dark matter scenarios: axion-like particle dark matter and primordial black hole dark matter. We begin with radio telescope probes on axion-like dark matter. We will discuss the axion-photon conversion around neutron stars which results in the radio emission and the 21 cm probes through the effects on large scale structure formation suppression. We then turn our at...</p>

2023.11.24

Tidal Disruption Events: Probes of Accretion Physics and Black Hole Demographics

<p>Tidal disruption events (TDEs) provide unique laboratories to&nbsp;study the demographics, immediate stellar and gaseous environments, and&nbsp;accretion physics of the massive black hole population. Over the past&nbsp;few years, time domain sky surveys such as the optical Zwicky Transient&nbsp;Facility (ZTF) have led to a surge of TDE discoveries in galaxy centers.&nbsp;This talk highlights our efforts to constrain th...</p>

2023.11.21

High contrast imaging science with coronagraphic instruments

<p>While high-contrast imaging surveys in the past decade have produced only a handful of self-luminous exoplanets, they opened new gates for studying the forming environments of planetary systems. With multi-epoch and multi-wavelength imaging, I will talk about our ongoing efforts on scientific expeditions using current flagship observatories. They include (1) pinpointing the orbits of hidden pla...</p>

2023.11.10

Exploring galaxy dark matter with dynamical models using combined stellar and HI kinematics

<p>The dynamical modelling technique is one of the major methods to measure the dark matter distribution in galaxies. Due to the degeneracy of baryonic and dark matter and the limitation of extended tracers in galaxies, accurate measurements of dark matter distribution in large sample of galaxies are still inadequate. We introduce our method to constrain the dark matter distribution in galaxies wi...</p>

2023.11.13

Understanding the galaxy formation and metal-enrichment in the view of gas-regulator framework

<p>Star-forming galaxies are actively accreting gas from surrounding materials during the cosmic time, while the feedback from star formation on the other hand blows the gas away as well as enriches the inter-stellar/-galactic medium. The interplay between inflow, outflow and star formation is then the key to understand the formation and evolution of star-forming galaxies, as well as the relevant...</p>

2023.10.24

An Overview of Stellar Evolution and Pollution in AGN Disk (SEPAD) and their Implication on the Stellar Dynamics in the Galactic Center and around other Supermassive Black Holes

<p>Extended regions of accretion disks around supermassive black holes in bright AGNs are prone to gravitational instability, star formation and stellar dynamical evolution with feedback to the disks&#39; structure. Spectroscopic data provide vital clues on the stellar and residual black hole populations. Their dynamical interaction with each other, their natal disks, and other massive companions in a...</p>

2023.09.11

Stellar Object Formation and Evolution in AGN Disks

<p>Study of stellar objects embedded in AGN accretion disks around massive Black Holes have been motivated by i) the disk of stars that formed in-situ in the galactic center; ii) the redshift independence of metallicity in AGN disks, which also suggest in-situ pollution; iii) massive LIGO-Virgo gravitational wave sources that possibly evolved in a gas rich environment, and iv) quasi-periodic erupt...</p>

2023.09.07

Probing Galaxy Formation in the Cosmic Web at z~3: A View with the James Webb Space Telescope

<p>Galaxies are not isolated islands in the Universe. Across the cosmic time, they assemble and evolve while frequently interacting with the ambient cosmic gas, namely the circum- and inter-galactic media (CGM/IGM), which belongs to the large-scale structure named the cosmic web. However, specifically what roles this large-scale environment plays in galaxy formation remains as a key open question ...</p>