(Left) Blowout size (s_BO,eff) derived from numerical calculations (see Sect. 2.1.3) for main-sequence stars F4-M4 at an age of 4 Gyr (2-3 Gyr for F-type stars). The values for stars later than ~ K2-type are not shown as they do not exist. (Right) Minimum values of ψ are required for s_BO,eff to exist (ψ_min,sBO) for stars without radiative blowout size, and their ψ values are estimated in this study (Fig. 3). The star shape indicates the value corresponding to AU Mic from Plavchan et al. (2005).