Ages of late spectral type Vega-like stars
  We have estimated the ages of eight late-type Vega-like stars by using standard age dating methods for single late-type stars, e.g., location on the color magnitude diagram, Li 6708 angstrom absorption, CaII H&K emission, X-ray luminosity, and stellar kinematic population. With the exception of the very unusual pre-main sequence star system HD 98800, all the late-type Vega-like stars are the same age as the Hyades cluster (600-800 Myr) or older. 
Inseok Song, J.-P. Caillault, David Barrado y Navascues, John   Stauffer, and Sofia Randich