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2024.07.02

Analytical Insights into Dark Matter Deficient Galaxies

<p>Recent observations reported a puzzling dearth of dark matter (DM) in a fraction of massive high-z galaxies and dwarf galaxies, challenging current simulation predictions within the standard ΛCDM scenario. This discrepancy underscores our limited understanding of the halo and galaxy structural evolution. Here, I will present a novel unified analytical framework for galaxy dynamical evolution d...</p>

2024.06.25

Probing Cosmic Reionization with JWST/NIRSpec Ly Observations

<p>The JWST is ushering in a new era of observing galaxies in the reionization era, providing us new insights into this last major phase transition of the Universe. The Ly-alpha emission from young star forming galaxies, which is sensitive to the presence of neutral HI along the line of sight, has been used as an important probe of the reionization process. JWST/NIRSpec offers spectroscopic capabi...</p>

2024.06.18

The strong-lensing revolution in the JWST-Rubin-Roman era: from resolving the Hubble tension to constraining baryonic feedback

<p>Despite the remarkable success of the Lambda Cold Dark Matter (LCDM) cosmological model, several challenges have recently emerged. One of the most prominent is the “Hubble tension”: the Hubble expansion rate (H_0) measured using the Cepheid-calibrated distance ladder of type Ia supernovae and the value extrapolated from the cosmic microwave background using LCDM disagree by 5 standard deviati...</p>

2024.06.11

Perturbative Modeling of Galaxy Large-scale Structure

<p>Current and future galaxy surveys such as HETDEX, DESI, Euclid, PFS, and SPHEREx aim to address fundamental questions in cosmology. For all these galaxy surveys, galaxy clustering is the primary observable, so modeling the nonlinearities in galaxy clustering is essential to decipher the survey data. Perturbative modeling offers an efficient, flexible, and robust method to achieve this.In this t...</p>

2024.06.04

Spatially Resolved Star Formation of Galaxies at z ~ 1 - 3 from HST and JWST Observations

<p>Investigating spatially resolved properties of galaxies offers important constraints on the mechanisms by which galaxies form stars and grow in stellar mass. The James Webb Space Telescope (JWST) not only facilitates a systematic exploration of high redshift galaxies, but also enables a detailed study of the rest-frame mid-infrared (mid-IR) and the optical emission lines of galaxies at intermed...</p>

2024.05.28

Mathematica code for calculating CMB anisotropy

<p>The Planck mission measures the cosmic microwave background (CMB) with unprecedentedly precision. The angular spectra extracted from Planck&#39;s CMB measurements can be used to test gravitational theories and cosmological models. This is done by comparing the observational results with theoretical predictions that can be calculated by solving together the Boltzmann equation governing the evolution...</p>

2024.05.21

Galaxy Assembly Revealed by the Life Cycle of Star Clusters

<p>The life cycle of a star cluster can be broken into three epochs: 1) the birth of the cluster; 2) the long phase when the cluster evolves in gravitational equilibrium, gradually losing stars; and 3) the death of the cluster when it dissolves into a stream of stars. The clusters in the first epoch directly record the initial properties inherited from the host galaxy. The evolved clusters during ...</p>

2024.05.08

Dark Matter Halo and its Structure, Assembly, and Clustering

<p>Dark matter halos are the major composition of the cosmic structures in our Universe and, therefore, play a central role in studying galaxies and cosmology. In cosmological N-body simulations, dark matter halos can be investigated from three perspectives: their structures, assembly histories, and spatial clustering. This talk will focus on our recent work on this topic. In the first part, I wil...</p>

2024.04.23

Gas Accretion and AGN Feedback in the Late Stage Evolution of Massive Ellipticals

<p>Observations indicate that massive elliptical galaxies in the contemporary universe exhibit both low star formation rates and low AGN luminosity. This raises a question: Given continuous gas accretion, how do these massive ellipticals maintain their quiescent state? SMBH feedback is a widely accepted solution to this issue, yet the mechanisms how it prevents gas accretion and subsequent star fo...</p>

2024.04.16

Modelling sub-millimetre emission from the cold circumgalactic medium around high redshift galaxies

<p>TBC</p>