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Welcome to Yonsei Observable UNiverse Group (YOUNG, 연세관측우주론그룹)

Group leader Myungkook James Jee (지명국), mkjee@yonsei.ac.kr Professor in Department of Astronomy, Yonsei University Ph.D. from Johns Hopkins University Research interests: - gravitational strong & weak lensing - astronomical instrumentation - observational cosmology and nature of dark matter - galaxy cluster plasma physics - machine learning

Publication in ADS
Google scholar

Research highlights

	File:Perseus dm.jpg The distribution of dark matter (in blue) is overlayed on an image taken by Hyper Sprime-Cam on the Subaru Telescope. The newly detected subcluster located near the galaxy NGC 1264 lies about 1.4 million light-years to the west (right side of the image) of Perseus’s central galaxy, NGC 1275. A faint bridge connects the two structures.
	Dark matter in the Coma Cluster region. The distribution of dark matter calculated based on this research (dark green cloud) is overlayed on an image of the Coma Cluster and more distant background galaxies taken by the Subaru Telescope. Strands of dark matter can be seen extending millions of light years.
	ICL fraction evolution. Filled red circles are the current results. We extrapolated the best-fit Sérsic profiles to the same aperture to estimate the total ICL flux. The dashed line and pink shade show the best-fit linear regression and its 68% uncertainty, respectively. We weighted all data points equally and adjusted them in such a way that the reduced χ2 value becomes unity. The comparison between our high-redshift and the literature low-redshift samples shows that there is no significant evolution of the ICL fraction with redshift in observation, which contradicts the current theoretical prediction.