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2025.06.10

New models to interpret near and far observations of the metal-poor Universe

The Universe started without the heavy elements that make the complexity of our surrounding world (e.g. carbon, oxygen). In this talk, I will showcase advances in the numerical modelling of how these chemical elements are produced in stars, how they are dispersed around young galaxies by energetic events, and how they get ionized to power the emission and absorption lines we observe in the spec...

2025.06.16

Towards a new generation of reflection models for precision measurements of accreting black holes

Blurred reflection features are commonly observed in the X-ray spectra of accreting black holes. In the presence of high-quality data and with the correct astrophysical model, X-ray reflection spectroscopy is a powerful tool to probe the strong gravity region of black holes, study the morphology of the accreting matter, measure black hole spins, and test Einstein's theory of General Relativity ...

2025.06.19

Probing wandering black holes with off-nuclear tidal disruption events

<p>The hierarchical assembly of galaxies and dynamics in galactic nuclei naturally predict a significant population of off-nuclear massive black holes (MBHs), yet direct observational evidence remains scarce. The demographics of these off-nuclear MBHs offer critical insights into the formation of MBH mergers, the nature of ultra-compact dwarf galaxies, and the co-evolution of MBHs and their host g...</p>

2025.05.14

Non-thermal pressure in galaxy clusters: methods, models, constraints

<p>I will discuss the role of non-thermal pressure support as a major source of the difference between the hydrostatic and the total ``true&#39;&#39; halo mass in galaxy clusters. I will present new models and methods to constrain the non-thermal pressure, highlighting the role of the next generation of X-ray observatories, like XRISM and NewAthena, in constructing a consistent picture of the formation an...</p>

2025.05.16

从小尺度到宇宙大尺度探索超弥散星系的形成机制 Unveiling the Formation Mechanisms of Ultra-Diffuse Galaxies: From Small Scale to Large Scale

<p>Ultra-Diffuse Galaxies (UDGs) represent an extraordinary class of galaxies with effective radii comparable to the Milky Way yet stellar masses only 1/100 to 1/1000 of our Galaxy. Found in a variety of cosmic environments—from galaxy clusters and groups to large-scale filaments and cosmic voids—their origins remain a subject of intense debate, positioning them at the forefront of extragalactic...</p>

2025.06.11

Local Group Analogs in a cosmological context: Relating the velocity structure to the cosmic web

<p>The Local Group (LG), as a gravitationally bound system of the Milky Way and Andromeda, as well as their satellites, is a cornerstone of near-field cosmology. However, its utility as a cosmological probe requires understanding how it is related to the cosmic web. Using the ABACUSSUMMIT simulation, we identify LG analogues and quantify their environmental dependence. We find that the coupling en...</p>

2025.06.05

Ultra-hot Jupiter's atmosphere unveiled by high-resolution spectroscopy

<p>Ultra-hot Jupiter is a class of giant exoplanets with extremely high temperatures. Due to their unique chemical and physical properties, this class of exoplanet have become a popular research subject in recent years. In this talk, I will present observed results of ultra-hot Jupiters using both transmission and emission spectroscopy. We conducted a survey of a dozen ultra-hot Jupiters using gro...</p>

2025.05.29

Exploring Compact Object Binaries via Optical Observations and Surveys

<p>Compact objects, including white dwarfs, neutron stars, and black holes, serve as exceptional laboratories for probing fundamental physical processes under extreme conditions in the universe. Binary systems hosting these compact objects represent a crucial pathway for characterizing their properties and advancing our understanding of accretion physics and stellar evolution. While compact object...</p>

2025.05.22

The Restless (the birth of the periodic table)

<p>Following the Big Bang the Universe was homogeneous in matter, energy and barren of chemistry. It is the stars which, through their life and death, built up the periodic table. Astronomers have now identified several classes of cosmic explosions of which supernovae constitute the largest group. The Palomar Transient Factory was an innovative 2-telescope, and its successor, the Zwicky Transient ...</p>

2025.05.15

A Possible Metal-dominated Atmosphere below the Thick Aerosols of GJ 1214 b Suggested by Its JWST Panchromatic Transmission Spectrum

<p>GJ1214b is the archetype low-density sub-Neptune orbiting around a M-dwarf. The bulk composition of GJ1214b is of great interest to explore its origin; however, previous studies suffered from a degeneracy between a rocky core with a hydrogen-rich envelope or an icy core with a water-rich envelope. To break the degeneracy, atmospheric observations had been conducted for over a decade; however, t...</p>