Speaker: Claire Le Cras

We model the spectra of massive galaxies to determine the ages of their stars. We focus on the Ultraviolet (UV) spectrum which is usually associated with newly formed stars but can be produced by older stars. We model 8 absorption features situated in the UV between 2200-3200A which trace several chemical elements such as Magnesium and Iron. Using these we investigate whether any individual features (or combination) can differentiate between the UV produced by a young population and that from an old one. We test our method using a large sample of massive, luminous, galaxies taken from the Sloan Digital Sky Survey (SDSS) – III / Baryon Oscillation Spectroscopic Survey (BOSS) which are predominately old and find 3 features which can be used to determine whether the UV comes from a young or old population.

The Dance of Stars is a new outreach activity designed to explore how information and theories in physics can be interpreted through dance. In this project a trial workshop was set up with a group of 7 dancers (aged 12-17) in which the different stages of a massive star’s life cycle were explained to them. Using this information the dancers worked as a group to choreograph a routine showing the different stages through dance and other movement resulting in a 3 minute routine expressing some of the key information in a new and unique manner.