CAN Li RICH GIANT STARS EJECT SHELLS ?
Ramiro de lá Reza(1) and Natalia A. Drake(1,2)

(1) Observatório Nacional/MCTI - Rio de Janeiro/Brasil
(2) Astronomical Institute St Petersburg University/Rússia 

We discuss here the different observational strategies, by images and by spectroscopy, to detect a predicted detached shell 
ejection of RGB stars when they get enriched by fresh Li in an localized region of the RGB. Based on the far-IR excesses of 
Li rich and Li poor giants, we proposed a model (de la Reza et al. 1996, 1997) in which a rapid Li enrichment occurs, followed 
by a shell ejection out of the star. A subsequent relatively rapid Li depletion of the remaining Li at the star surface also 
occurs. An eventual detection of these detached shells will give a strong indication that all low-mass RGB stars pass by a Li 
rich phase. 
de la Reza et al. ApJ 456,L115 (1996)   de lá Reza et al. ApJ 482,L77 (1997)