Age-Dating of Starburst Galaxies

This review covers age-dating methods applied to young stellar populations in starburst galaxies with ages of 10^8 yr and less. First, recent advances in stellar modeling, both for the interior and the atmospheres, are discussed and spectral lines and colors suitable for age-dating are identified. These age indicators are then applied to single stellar populations, the simplest building blocks of starbursts. More complex systems, such as luminous starburst galaxies, are a challenge for chronometric measurements. The dust reddening, metallicity, stellar initial mass function, and inhomogeneities of the interstellar medium introduce degeneracies which are often hard to resolve. Finally, some shortcomings in the stellar models are highlighted.