科学研究
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2024.03.08
Pathway to high-z SMBHs: seed formation and growth in the statistical perspective
The early evolution of the black hole mass function (BHMF) and quasar luminosity function (QLF) encodes key information on the physics determining the radiative and accretion processes of black holes (BHs) growing in high-redshift galaxies. Starting from the formation of seed BHs as their parent halos evolve, we study primordial gas collapse in the biased quasar host halos, computing gas chemic...
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2024.03.07
Galaxy-halo connection and near-field cosmology with numerical and semi-analytic methods
In our modern understanding of the Universe, dark matter (DM) constitutes ~85% of the total mass and forms gravitationally bound halos which are the sites for galaxy formation. Galaxies contain information of their host halos, and halos react to the baryonic processes of the inhabitant galaxies — their connections are essential for understanding galaxy formation, and enable us to derive fundam...
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2024.03.05
Towards a Unified Model of Dwarf Galaxy Star Formation and Halo Connection with UniverseMachine
Dwarf galaxies provide rich constraints on galaxy formation, reionization, and the nature of dark matter. However, flexible models of their star formation histories in a cosmological context are lacking. We introduce a novel framework for connecting dwarf galaxy dark matter assemblies and star formation histories based on the empirical model UniverseMachine (UM). Our framework is flexible, such...
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2024.02.28
Weak Lensing Without Shape Noise
Weak gravitational lensing imprints a coherent distortion onto the observed shapes of distant galaxies. At the image level, this gravitational shear degenerates with the intrinsic shape of galaxies, and the weak lensing signal-to-noise from an individual galaxy is of order 0.01. I will describe Kinematic Lensing, a new technique combining imaging and galaxy kinematics to measure weak lensing wi...
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2024.01.12
Ultra-compact dwarf galaxies caught in the act of transformation
In the past two decades, systematic studies have revealed hundreds of ultra-compact dwarf galaxies (UCDs) in the nearby Universe. While similar in appearance to massive globular clusters, the detection of extended stellar envelopes, complex star formation histories, elevated mass-to-light ratio, and supermassive black holes suggest that some UCDs are remnant nuclear star clusters of tidally-str...
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