HR diagram showing evolutionary sequences for different stellar masses. Sequences shown in solid lines correspond to cases without overshooting, while those in short-dashed lines have α_ov = 0.1 and long-dashed lines correspond to evolutionary sequences with α_ov = 0.3. The box indicates the values of log(T_eff) and log(L/L_⊙) derived in Sect. 2. Colour-coding shows the age of each evolutionary sequence. Selected models listed in Table 8 are shown by diamonds. The green circle shows the position of our best-fit model (see main text).