A&A 590, A94 (2016) Astronomy DOI: 10.1051/0004-6361/201527583 & c ESO 2016 Astrophysics Mass effect on the lithium abundance evolution of open clusters: Hyades, NGC 752, and M 67 M. Castro1, T. Duarte1, G. Pace2, and J.-D. do Nascimento Jr.1; 3 1 Departamento de Física Teórica e Experimental, Universidade Federal do Rio Grande do Norte, 59072-970 Natal, RN, Brazil e-mail:
[email protected] 2 Instituto de Astrofísica e Ciência do Espaço, Universidade do Porto, Rua das Estrelas, 4150-762 Porto, Portugal 3 Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138, USA Received 16 October 2015 / Accepted 12 March 2016 ABSTRACT Lithium abundances in open clusters provide an effective way of probing mixing processes in the interior of solar-type stars and convection is not the only mixing mechanism at work. To understand which mixing mechanisms are occurring in low-mass stars, we test non-standard models, which were calibrated using the Sun, with observations of three open clusters of different ages, the Hyades, NGC 752, and M 67. We collected all available data, and for the open cluster NGC 752, we redetermine the equivalent widths and the lithium abundances. Two sets of evolutionary models were computed, one grid of only standard models with microscopic diffusion and one grid with rotation-induced mixing, at metallicity [Fe/H] = 0.13, 0.0, and 0.01 dex, respectively, using the Toulouse-Geneva evolution code. We compare observations with models in a color–magnitude diagram for each cluster to infer a cluster age and a stellar mass for each cluster member.