The low mas end of the young cluster IC2391
  By collecting optical and infrared photometry, as well as medium resolution spectroscopy, we have discovered a sample of low mass stars and brwon dwarfs in the young cluster IC2391. Using the lithium depletion boundary near the substellar limit, we have estimated the age of the cluster as ~50 Myr. We have also estudied the H(alpha) emission in this sample. 
David Barrado y Navascues (1), John R. Stauffer (2) ((1) Laboratorio   de Astrofisica Espacial y Fisica Fundamental, Spain (...