Vanadium Oxide in the Spectra of Mira Variables
As a preliminary step in deducing Teff and log (g) of Mira variables as a function of phase, a comparison is made between spectra synthesized from LTE stellar atmosphere models and observed spectra. The observed spectra show obvious vanadium oxide (VO) absorption bands. However, the molecular line list used to produce the synthetic spectra does not include the bound-bound VO opacities. The wavenumbers, line oscillator strengths, and lowest energy levels are needed to calculate these opacities. The equations, constants, and experimentally determined factors required to calculate the line oscillator strengths and lowest energy levels from experimentally determined wavenumbers are presented. The effect of including the wavenumbers, line oscillator strengths, and lowest energy levels of the VO BX (0, 0) band are calculated and show the expected absorption features observed in the spectra of Mira variables. In the VO B-X (0, 0) band the line oscillator strengths range from about 0.05 to 3.
Castelaz, Michael W.; Luttermoser, Donald G.; and Piontek, Robert A.. 2000. Vanadium Oxide in the Spectra of Mira Variables. Astrophysical Journal. Vol.538(1 PART 1). 341-345. https://doi.org/10.1086/309121 ISSN: 0004-637X