Absorption non-symmetric ion-atom processes in helium-rich white dwarf atmospheres

Abstract

In this work the processes of absorption charge-exchange and photo-association in He+H${}^{+}$ collisions together with the process of ion HeH${}^{+}$ photo-dissociation are considered as factors of influence on the opacity of the atmospheres of helium-rich white dwarfs in the far UV and EUV region. It is shown that they should be taken into account even in the cases of the atmospheres of white dwarfs with H:He =$10^{-5}$. Than, it is established that in the cases of white dwarfs with H:He $\gtrsim 10^{-4}$, particulary when H:He $\approx 10^{-3}$, these processes have to be included \emph{ab initio} in the corresponding models of their atmospheres, since in the far UV and EUV region they become dominant with respect to the known symmetric ion-atom absorption processes.

Accepted in Monthly Notices of the Royal Astronomical Society

References in corpus (3)

• A Comprehensive Spectroscopic Analysis of DB White Dwarfs
• On the Spectral Evolution of Cool, Helium-Atmosphere White Dwarfs: Detailed Spectroscopic and Photometric Analysis of DZ Stars
• The non-symmetric ion-atom radiative processes in the stellar atmospheres

Cited by in corpus (3)

• The ion-atom absorption processes as one of the factors of the influence on the sunspot opacity
• MOL-D: A Collisional Database and Web Service within the Virtual Atomic and Molecular Data Center
• Mol-D a Database and a Web Service within the Serbian Virtual Observatory and the Virtual Atomic and Molecular Data Centre