Fraction of the total red giant branch duration spent with a surface equatorial rotation velocity that is higher than 8 km s^-1 after an engulfment. Upper left panel: case of a 1.5 M_⊙ with an initial rotation Ω_ini/ Ω_crit = 0.1. Upper right panel: same as the upper left panel, but with Ω_ini/ Ω_crit = 0.5. Lower left panel: same as the upper left panel, but for a star of mass 2.0 M_⊙. Lower right panel: same as the lower left panel, but with Ω_ini/ Ω_crit = 0.5.