Abnormal behaviour of lithium in coeval stars?

LLORENTE DE ANDRÉS, F.; MORALES-DURÁ, C.; CHAVERO, C.; DE LA REZA, R.

Teruel

Congreso; Highlights of Spanish Astrophysics VIII; 2014

SEA

Due to its fragility, the light element lithium (Li) is an excellent andvery used indicator of stellar processes. Our interest here is toexplore and try to understand the Li dispersion observed in some stellaropen clusters which are not explained by the standard theories. Atypical and historical case, for example, is that found for stars coolerthan the stellar effective temperature Teff ? 5500 K in thePleiades cluster with an age of ? 130 My (see details in Figure 2of this poster). What is the mechanism that provoques this dispersion?.Up to now, mainly three mechanisms are being proposed : (1) Episodicaccretion during the protostellar phase (Barafee et al. 2010). (2)Rotational stellar internal mixing shears due to a star-disk interaction(Eggenberger at al. 2012) and (3) Li depletion by an increased stellarradius (Somers et al. 2014). We will explore this problem using therotational option (2) (Chavero et al. 2014) and also identifying stellarinterlopers in some groups.