Surface rotation period as function of age for models with 0.55M_⊙ (solid lines), 0.7M_⊙ (dashed lines) and 1M_⊙ (doted lines). The color corresponds to various values of additional viscosity (in unit of cm² s⁻¹). For all models, the initial conditions include a disk with a lifetime of 5 Myrs and a period of rotation of 10 days. Gray plus symbols correspond to the measured rotation period of stars in open clusters NGC2547 (40 Myrs), aPersei (85 Myrs), the Pleiades (125 Myrs), Praesepe (600 Myrs) and the Hyades (700 Myrs). Estimated properties taken from Wright et al. (2011).