Astronomy Colloquium: Chelsea Spengler
Date: Mon. January 14th, 2019, 2:15 pm-3:15 pmLocation: Sears 552
Nuclear Star Clusters in Virgo: Scaling relations, stellar populations, and the role of environment
Chelsea Spengler (Pontificia Universidad Católica de Chile)
It is readily accepted that many galaxies are inhabited by dense, compact objects deep in their centers, manifesting as supermassive black holes and/or nuclear star clusters (NSCs). Their widespread presence and apparent similar scaling relations with properties of their hosts implies that these black holes and NSCs are two related flavours of central massive object that play essential roles in their hosts’ evolution. How do these NSCs form? How do they relate to black holes and their host galaxies? Does environment regulate their formation mechanisms? Addressing these questions requires sensitive observations of lower-mass galaxies where NSCs dominate. The unprecedented depth and coverage of the Next Generation Virgo Cluster Survey (NGVS) — expanding our sample of Virgo Cluster members to new low-mass regimes — enables a thorough exploration of the photometric properties of NSCs throughout Virgo, ranging from the dense cluster core to more diffuse groups still falling into the cluster potential. In this talk, I will describe ongoing efforts to constrain the effects of local environment on the formation and growth of NSCs. I will introduce a novel density-based hierarchical clustering algorithm used to identify various substructures and environments throughout Virgo using the coordinates of 3,687 Virgo members in the NGVS. I will then present a comparison of the properties of NSCs, their hosts, and non-nucleated counterparts in the different cluster substructures and discuss the implications of these results for NSC formation and evolution.