The disagreement between observations and theoretical predictions for surface 7Li abundances is still a challenging issue for stellar modellers. We re-examine the level of disagreement in the case of five young open clusters, namely Ic2602, alpha Per, Pleiades, Blanco 1, and Ngc 2516, and few double-lined eclipsing binaries. The calculations have been performed with our up-to-date standard evolutionary code, paying particular attention to the uncertainty evaluation on surface 7Li. We found that to reproduce the observed Li(T_eff) profile, a convection efficiency much lower than the one needed to fit MS stars colour of each cluster is required. Such value of the mixing length parameter results to be independent of the age and of the chemical composition of the cluster.
7Li in young open clusters and binary systems
TOGNELLI, EMANUELE;DEGL'INNOCENTI, SCILLA;PRADA MORONI, PIER GIORGIO
2015-01-01
Abstract
The disagreement between observations and theoretical predictions for surface 7Li abundances is still a challenging issue for stellar modellers. We re-examine the level of disagreement in the case of five young open clusters, namely Ic2602, alpha Per, Pleiades, Blanco 1, and Ngc 2516, and few double-lined eclipsing binaries. The calculations have been performed with our up-to-date standard evolutionary code, paying particular attention to the uncertainty evaluation on surface 7Li. We found that to reproduce the observed Li(T_eff) profile, a convection efficiency much lower than the one needed to fit MS stars colour of each cluster is required. Such value of the mixing length parameter results to be independent of the age and of the chemical composition of the cluster.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
