Figure 3.

Linear fits by the experimental ${\mathrm{s}}_{\mathrm{t}}^0{({\mathrm{W}}_{\text{AF},}\mathrm{w},10)}_{\text{MV}}$ values (obtained with a field $\mathrm{L}=10\times 10{\text{cm}}^2$) as function of ${\mathrm{W}}_{\text{AF}}$, for the 6 MV (dotted line), 10 MV (thin line), and 15 MV (heavy line) beams. The fits reported here were obtained by SP thicknesses $\mathrm{w}=10,22$, and 42 cm and using $10\times 10\hspace{0.17em}{\text{cm}}^2$ fields.