Hydrogen Alpha Profiles in Cepheids

Theoretical Hα profiles have been used by Rodgers and Bell (hereafter denoted by RB) to obtain the effective temperatures of several cepheid variable stars. They find that the profiles are sufficiently sensitive to temperature to enable them to determine temperatures which are accurate to within about 300°, while being insensitive to other factors such as gravity or the form of the temperature distribution in the model atmosphere.