Calcu lation of Rovibronic Transition Intens ities for D iatomic Molecules

Stars ha ving remarkable emissi on lines in the optical spectra are called emiss ion-line stars and widely distribute d on the Hertzsprung-Russell diagr am includin g various ste llar types.۱ In addition to line positions, knowledge of Einstein A coefficients for rovibronic transitions has important applicatio ns in astro physics.۲ E xperimentally, Einstei n A coefficients can be determined indirectl y via lifetime measurement; however, this lifeti me is related to the rate of radiative decay ofan excited stat e to all lower energy levels.Magnesium hydride is an important molecule in different astrophysically environments. Lines of the A۲II X ۲Σ+transition have bee n detected i n different stellar region s such as t he solar photosphere,۳ the spectra of sunspot,۴ nearby L dwarfs,۵ and late-ty pe stars.۶ In addition,theBƍ۲Σ+ X ۲Σ+bands have been detected in su nspot umbral spectra.۷

کلیدواژه ها:

Line Int ensities ، Einstein A coefficient ، MgH ، Astroche mistry