BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Biomedical Mathematics Group - ECPv6.15.20//NONSGML v1.0//EN
CALSCALE:GREGORIAN
METHOD:PUBLISH
X-WR-CALNAME:Biomedical Mathematics Group
X-ORIGINAL-URL:https://www.ibs.re.kr/bimag
X-WR-CALDESC:Events for Biomedical Mathematics Group
REFRESH-INTERVAL;VALUE=DURATION:PT1H
X-Robots-Tag:noindex
X-PUBLISHED-TTL:PT1H
BEGIN:VTIMEZONE
TZID:Asia/Seoul
BEGIN:STANDARD
TZOFFSETFROM:+0900
TZOFFSETTO:+0900
TZNAME:KST
DTSTART:20230101T000000
END:STANDARD
END:VTIMEZONE
BEGIN:VEVENT
DTSTART;TZID=Asia/Seoul:20240625T140000
DTEND;TZID=Asia/Seoul:20240625T150000
DTSTAMP:20260505T183822
CREATED:20240623T122242Z
LAST-MODIFIED:20240625T002727Z
UID:9721-1719324000-1719327600@www.ibs.re.kr
SUMMARY:Hyungsuk Tak\, Statistical Challenges in Astronomical Time Delay Estimation (Cancelled)
DESCRIPTION:I present time delay estimation problems in astronomy as a part of time delay cosmography to infer the Hubble constant\, the current expansion rate of the Universe. Time delay cosmography is based on strong gravitational lensing\, an effect that multiple images of the same astronomical object appear in the sky because paths of the light (from the object to the Earth) are bent by the strong gravitational field of an intervening galaxy. By measuring brightness of multiply-lensed images\, we obtain several time series data of brightness\, and time delays can be inferred by modeling these data. I focus on challenges in modeling these time series data and computational issues in fitting the models. In particular\, I explain continuous-time auto-regressive models to account for stochastic variability of the time series data\, and several Monte Carlo samplers to sample from the target posterior distributions with multiple modes. At the end of the talk\, I show how these time delays estimates contribute to the Hubble constant estimation. Two main references of this talk are arXiv2207.09327 and arXiv2308.13018.
URL:https://www.ibs.re.kr/bimag/event/hyungsuk-tak-statistical-challenges-in-astronomical-time-delay-estimation/
LOCATION:B232 Seminar Room\, IBS\, 55 Expo-ro Yuseong-gu\, Daejeon\, Daejeon\, 34126\, Korea\, Republic of
CATEGORIES:Biomedical Mathematics Seminar
ORGANIZER;CN="Jae Kyoung Kim":MAILTO:jaekkim@kaist.ac.kr
END:VEVENT
END:VCALENDAR