Observational evidence of the evolutionary enhancement of the Be phenomenon

Author(s): Fabregat, J.

Book Editor(s): Stefl, S; Owocki, SP; Okazaki, AT

Conference: Conference on Active OB-Stars – Laboratories for Stellar and Circumstellar Physics Location: Sapporo, JAPAN Date: AUG 29-SEP 02, 2005

Sponsor(s): Hokkaido Univ, 21st Cent COE Program Topol Sci & Technol; Japan Soc Promot Sci

Source: Active OB-Stars: Laboratories for Stellar and Circumstellar Physics, Proceedings  Book Series: ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES   Volume: 361   Pages: 363-369   Published: 2007

Observational results obtained during the past few years support the existence of an evolutionary enhancement of the Be phenomenon along the B stars main sequence lifetime. In this paper we analyze recent related work, including: i/ the study of the frequency of Be stars in open clusters as a function of the cluster age; ii/the detailed analysis of the frequency of Be stars as a function of the spectral subtype in a few well studied young clusters; iii/ the determination of the evolutionary status of Be stars in the galactic field.