Globular Cluster Stellar Population Synthesis using NLTE Integrated Light Spectra

Thursday, 14. March 2019, 14:00 - 15:30
Location Bibliothek
Globular clusters can provide valuable clues about the chemical and dynamical evolution histories of galaxies, informing galaxy formation theories.  They are among the oldest and brightest objects within their host galaxies, making even extragalactic GCs easily observable.  Historically, Milky Way GC populations have been characterized by observing their red giant members.  However, extragalactic clusters are found at distances where individual members cannot be spatially resolved.  In these cases, the only observable is the integrated light of the cluster.  In this talk, I present an investigation of McWilliam & Bernstein's (2008) GC integrated light population synthesis method, focusing on the impact of NLTE modelling effects, and demonstrate that NLTE modelling can reduce the uncertainties in cluster age and metallicity by half.

: Mitchell Young (Space Research Institute, Austrian Academy of Sciences, Graz, Austria)