Quasi-molecular satellites of Lyman β in ORFEUS observations of DA white dwarfs
نویسندگان
چکیده
Quasi-molecular satellite features of Ly β were first observed in a HUT spectrum of the DA white dwarf Wolf 1346 and interpreted by Koester et al. (1996). In this paper we study the dependence of these features on temperature and surface gravity in 4 additional DA observed with ORFEUS-SPAS II in 1996. For the interpretation we use theoretical atmosphere models which incorporate new profiles for Ly β. These have been calculated by Allard et al. (1998a) including the variation of the transition probability with distance between emitter and perturber. The new calculations for the general line shape, satellite positions and strengths are in very good agreement with the observations.
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