A Method for determining the physical parameters of hot supergiants based on spectral energy distribution analysis

Abstract

This study determines the physical parameters of B- and A-type hot supergiants through the construction and analysis of their spectral energy distributions (SEDs). These luminous stars are in the late stages of stellar evolution and are important for understanding stellar structure and the chemical evolution of galax ies. Although previous spectroscopic studies provided extensive information, our application of the com prehensive SED analysis represents a novel approach to further refine and validate these parameters. We refined the effective temperature Teff, surface gravity (log g), and interstellar extinction AV for a sample of 16 supergiants using multiwavelength photometry spanning from the ultraviolet to the infrared. A dedicated software package written in Fortran was used to convert observed magnitudes into physical fluxes and compare them with synthetic photometry derived from Castelli & Kurucz model atmospheres. The optimal parameter set for each star was obtained by minimizing the deviations between the observed and model SEDs, iterating over AV values. The resulting parameters show good agreement with those published in the literature, confirming the reliability of our approach.

Key words: supergiants, spectral energy distribution, interstellar extinction, effective temperature, surface gravity.