Photodissociation of HeH2+ and flux deficiency of stellar spectra
Abstract
Accurate quantal values of photodissociation cross sections have been calculated for HeH(2+) for the transition 2p sigma-3d sigma over the accessible range of 800-5800 A and an attempt has been made to explain whether this is the source of the well known ultraviolet flux deficiency observed by Stecher and Milligan in a number of early type stars. The cross sections were calculated for all the vibrational levels of the 2p sigma state for which the Boltzmann distribution has been assumed and for the two most probable rotational-level values at stellar temperatures of 20,000 K and 28,000 K. It has been concluded that HeH(2+) cannot be the source of such stellar opacity.
- Publication:
-
Journal of Physics B Atomic Molecular Physics
- Pub Date:
- November 1979
- DOI:
- 10.1088/0022-3700/12/21/012
- Bibcode:
- 1979JPhB...12.3553D
- Keywords:
-
- Helium;
- Hydrogen Ions;
- Molecular Ions;
- Photodissociation;
- Radiant Flux Density;
- Stellar Spectra;
- Cross Sections;
- Early Stars;
- Gas Dissociation;
- Helium Hydrogen Atmospheres;
- Stellar Atmospheres;
- Stellar Radiation;
- Ultraviolet Radiation;
- Vibrational Spectra;
- Astrophysics