Molecules in eta aquilae

Abstract

The total numbers Iφ(AB) of a given molecule AB in a column extending between τ=0 to τ=3.00 have been calculated for various phases ɸ of light variations in η Aql for the molecules CO, CN, C ₂ , OH, NH and CH. It is found that higher dissociation energy molecules form in higher layers at all phases and that for all the molecules considered the average geometrical depth of formation progressively shifts towards deeper layers as one proceeds from maximum phase to minimum phase of light variation in the star. Finally the dissociation equilibrium abundances of molecular species closely follow the shape of the light curve including its asymmetry and hump and that the abundances of higher dissociation energy molecules reflect this correspondence better.