Research
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2023.12.04
The “Missing baryons” in the cosmic web—what is it? Where is it? How much?
Previous studies of galaxy formation have shown that only 10 per cent of the cosmic baryons are in stars and galaxies, while 90 per cent of them are missing. In this talk, I will present several observational studies that coherently find significant evidences of the missing baryons. The first measurement is the cross-correlation between the thermal Sunyaev-Zeldovich effect with gravitational le...
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2023.11.13
The star formation, dust, and abundance of galaxies with CIB cross-correlations
The cosmic infrared background (CIB) is the accumulated infrared radiation mainly generated from dust emissions in star-forming galaxies. It bears rich information about star formation history, dust thermodynamics, and galaxy abundance in the distant Universe. The CIB auto- and cross-correlations with other large-scale structure (LSS) tracers have been used to probe the star formation, dust, an...
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2023.11.10
A two-phase model of galaxy formation: the growth of galaxies and supermassive black holes
I will describe a model for galaxy formation and the growth of supermassive black holes (SMBHs), based on the fact that cold dark matter halos form their gravitational potential wells through a fast phase with rapid change in the potential, and that the high universal baryon fraction makes cooled gas in halos self-gravitating and turbulent before it can form rotation-supported disks. Gas fragme...
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2023.10.30
Surveying galaxy clusters in the X-ray Universe: New results from eROSITA
The eROSITA X-ray telescope has performed four X-ray all-sky surveys since its launch in July 2019. In this talk, I will briefly overview eROSITA's early results on galaxy clusters, with an emphasis on the eFEDS PV-phase program. I will also report the latest progress on clusters and superclusters from the first eROSITA All-Sky Survey.BIODr. Ang Liu is a postdoc researcher at Max Planck Institu...
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2023.10.30
Cluster Intrinsic Alignment in DES Y1
Clusters of galaxies trace the most non-linear peaks in the cosmic density field. The weak gravitational lensing of background galaxies by clusters can allow us to infer their masses. However, galaxies associated with the local environment of the cluster can also be intrinsically aligned due to the local tidal gradient, contaminating any cosmology derived from the lensing signal. In this talk, ...
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