Back to Volume
Paper: Hydrogen Column Density Measurements toward White Dwarfs for D/H Studies
Volume: 348, Astrophysics in the Far Ultraviolet: Five Years of Discovery with FUSE
Page: 460
Authors: Vennes, S.; Chayer, P.; Dupuis, J.; Moos, H.W.; Lanz, T.
Abstract: Hot white dwarfs provide sources of extreme ultraviolet (EUV) radiation against which the photoionization continua of interstellar H I, He I, and He II are measured. The column density measurements depend on a detailed knowledge of the intrinsic EUV luminosity of the sources. We discuss recent progress in the study of low- and high-metallicity white dwarfs enabling a study of interstellar hydrogen and helium continuum absorptions toward many lines of sight. We compare the EUV-based measurements to recent hydrogen column density measurements based on Lyα line profiles and discuss the implications for D/H and O/H ratios in the local interstellar medium.
Back to Volume