MMag. Ulrike Kuchner
fields of interest
My main interests lie in the effects a change in environment has on star formation properties and AGN activity of cluster galaxies. The standard ΛCDM structure formation model motivates a number of physical processes that could alter the properties of cluster galaxies, responsible for the observed transformation of blue and star forming to red and passive galaxies since z~1. Through tidal interactions and gas collisions, which trigger the exchange and depletion of material, the morphologies and structures of galaxies can be changed and a quenching of star-formation through a buildup of the red sequence over time is observed. It becomes obvious that the environment influences the evolutionary history of galaxies in more or less dense regions differently. Galaxy clusters are ideal laboratories for the study of the behavior and interactions of galaxies within dense regions, and the dependence of galaxy properties on the environment.
Through the CLASH (Cluster Lensing and Supernova Survey with Hubble) collaboration, I am analyzing several well known massive clusters with regard to structure, SF and AGN activity, morphology and stellar population, through spectroscopic and photometric means using both multi-wavelength HST/ACS imaging and extensive VIMOS multiplex spectroscopy. Simultaneously, I am testing a proposed scenario of 3 superimposed cluster candidates through a Halpha narrow-band technique and try to verify their existence with star forming galaxy-overdensities. Both projects are connected through the same scientific motivation striving to shed some light on the connection between galaxies and their environment out to z~1.