Evolution of the eccentricity of CoRoT-23b  with time (in Myr) for two initial conditions (e = 0.5: solid lines and e = 0.8: dash lines) and four different values of the tidal quality factor Q_p: 10⁵, 3 × 10⁵, 10⁶, and 10⁷. The evolution of e was computed using Eq. (17) of Matsumura et al. (2010) and the parameters of Table 3. The horizontal blue line corresponds to the measured eccentricity of CoRoT-23b.