천문우주과학과

일시:  2019년 5월 30일 목요일 천문우주과학과 세미나실 (기2514호)

연사:  고종완 박사님 (한국천문연구원)

제목:  Finding the origin of intracluster light

초록:  Not all stars in the Universe are gravitationally bounded to galaxies. Since first discovered in 1951, observations have revealed that a significant fraction of stars fills the space between galaxies in local galaxy clusters, observed as diffuse intracluster light (ICL). Theoretical models provide mechanisms for the production of intracluster stars as tidally stripped material or debris generated through numerous galaxy interactions during the hierarchical growth of the galaxy cluster. These mechanisms predict that most intracluster stars in local galaxy clusters are long-accumulated material since z~1, corresponding to an age of the Universe of more than 6 billion years. However, there is no observational evidence to verify this prediction. In this talk, I will report observations of abundant ICL for massive galaxy clusters at z>1, and introduce a KASI project which is developing a pathfinder telescope optimized to probe low surface brightness structures such as ICL.