VPD of the stellar association Cen OB1. a) Open circles around the dots represent the 299 astrometric association members; points represent the rest of the stars of the region in the first analysis. b) Open circles represent the 86 astrometric and spectrophotometric members. c) Open circles represent the 52 astrometric and spectrophotometric association members obtained using the model proposed by Orellana et al. (2010).