Lifetimes of stars in the main sequence and the maximum mass of stars in the galactic disk

Generalized and interconsistent approximation formulas are derived to describe the relationship between the hydrogen-burning time and the zero-age stellar mass for the mass and elemental composition ranges characteristic of stars that have been formed during the lifetime of the universe. The maximum masses of population I stars are estimated based on the known statistical relationships among stellar characteristics that agree with observational data.