천문우주과학과

일시:  2020년 12월 3일 목요일 오후 4시
       (ZOOM 회의 ID:932 6693 1767, PW:612443)

연사:  최이나 박사님(고등과학원)

제목: Two phase formation of massive elliptical galaxies: the role of AGN feedback

 초록:  

 Massive elliptical galaxies have undergone dramatic structural evolution over the last 10 Gyr. Cosmological simulations of massive galaxy formation appear to show a two-phase character with a rapid early phase at z>2 during which "in situ" stars are formed within the galaxy from infalling cold gas followed by an extended phase since z<3 during which "ex situ" stars are primarily accreted. In this talk I will introduce the momentum based mechanical AGN feedback model in a three-dimensional hydrodynamics code, and a suite of cosmological hydrodynamical simulations I use to study the two phase nature of massive galaxy formation and the impact of AGN on physical properties of massive elliptical galaxies. I will discuss how AGN feedback plays an important role in making massive galaxies quench their star formation, as well as in making galaxies “bigger” in size. I will describe how the different feedback components affect the two-phase character of the stars ending up in the final galaxies, i.e., “in situ” stars that are created inside the galaxies themselves and those that are created outside and are accreted later on (ex situ / accreted).