Seminar:- Transient Detection for the 21st Century: Finding Gravitationally Lensed Transients in the HST/JWST Imaging
Optical and near-infrared transients discovered by the Hubble Space Telescope(HST) and the James Webb Space Telescope(JWST) behind galaxy cluster lenses include extremely magnified stars at redshift z>1 and multiply imaged SuperNovae (SNe). The detection of lensed stars and other microlensed sources behind galaxy clusters is scientifically important not only because it extends our viewing distance of individual stars that depict an earlier stage of galaxy evolution compared to our nearby galaxies, but also because it provides a unique probe of the dark microlenses and small-scale dark matter halos and subhalos in the clusters. On the other hand, strong-lensed SNe are especially valuable, because the lens magnification allows us to detect SNe at high redshifts, and the relative time delays of a multiply imaged SN enable us to study its evolution and to estimate the cosmic expansion rate. In this talk, the speaker will describe recent discoveries of these two types of gravitationally lensed transient phenomena. He will talk about the computer-vision techniques his team designed for their future multi-messenger observations and the application of these methods in the existing HST and JWST data.
時間:2023.06.12(一) 09:30
頻道:Zoom ID: 938-0592-1469 ← 2859
講者:Dr. CHEN WenLei (University of Minnesota, Twin Cities, US)
語言:英語
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【此屬轉載訊息,以主事單位發佈為準】
此活動由香港大學物理系主辦。