“…In order to demonstrate that at least in some situations, the accuracy of ( 7) is rather high, let us compare P(Z � 6, ε p � 600 keV) ≈ 3797 MeV cm 2 g −1 and P(Z � 6, ε p � 700 keV) ≈ 3440 MeV cm 2 g −1 , calculated using S p Cam from [14], with the same parameters, calculated using (7) and ΔZ � 2. Substituting S p Be and the stopping power of molecular oxygen for proton from [14] into (7), we obtain P(Z � 6, ε p � 600 keV) ≈ 3773 MeV cm 2 g −1 and P(Z � 6, ε p � 700 keV) ≈ 3424 MeV cm 2 g −1 . us, in these cases, the relative accuracy of ( 7) is better than 1%.…”