Ages of A-type Vega-like stars from uvbyβ photometry

We have estimated the ages of a sample of A-type Vega-like stars by using Stromgren uvby beta photometric data and theoretical evolutionary tracks. We find that 13% of these A stars have been reported as Vega-like stars in the literature and that the ages of this subset run the gamut from very young (50 Myr) to old (1 Gyr), with no obvious age difference compared to those of field A stars. We clearly show that the fractional IR luminosity decreases with the ages of Vega-like stars.