The temperature of the supergiant alpha Per

Because the bright supergiant alpha Per is located in cluster, and because its angular diameter has been measured, its log g is known observationally, as is its atmospheric microturbulence. Using these observed parameters, we compare its energy distribution derived from IUE spectra and B, V, R, I, J, and K with model atmospheres convolved with instrumental sensitivity functions. The two most important advances in this study as compared with previous work are the use of well-calibrated ultraviolet fluxes and the use of models with an appropriate microturbulence. Because the ultraviolet flux is sensitive to log g and microturbulence, as well as temperature, we fix log g at 1.5 and microturbulence at 4 km s(-1), and derive the temperature from the best fit to the energy distribution (6270 K). Other recent temperature determinations are discussed, as are the sources of error. (C) 1996 American Astronomical Society.