August 11-15, 2014


White dwarfs in the Galactic plane: an outlook of the dispersed and clustered population.

Roberto Raddi (University of Warwick)

D.Steeghs (University of Warwick), S.Catalan (University of Warwick), B.Gaensicke (University of Warwick), D.Koester (University of Kiel), J.J.Hermes (University of Warwick), and the EGAPS Consortium

The bulk of the know white dwarf population has been identified in large-area high-galactic latitude surveys, that were carried out primarily with extragalactic science goals in mind. In fact, more than 99% of the spectroscopically confirmed white dwarfs are found at Galactic latitudes |b| > 5 deg, mostly within the footprint of the Sloan Digital Sky Survey. The VST Photometric H-alpha Survey (VPHAS+) is the first deep multi-colour survey of unexplored lower galactic latitudes, carried out with the VLT Survey Telescope (VST). We use the ugri and Halpha photometry from the VPHAS+ to search for white dwarfs as candidate members of old (> 100 Myr) Galactic open clusters and, in combination with proper motions from PPMXL, to search for bright (g<=17) field white dwarfs. We discuss prospects for identifying white dwarfs in open clusters, which are important for setting an observational constraint on the initial-to-final mass relationship, as well as searching for nearby field white dwarfs, which are essential for volume-limited samples that can be used to study the white-dwarf luminosity function, which constrains the age and the star-formation history of the Galaxy.

Mode of presentation: poster