Inelastic collision spectrum of low-energy protons in the field of molecular excitations of water

The spectrum of inelastic collisions of low-energy protons in the field of molecular excitations of water is obtained in terms of the complex refractive index of water determined from optical measurements in the infrared, visible, and ultraviolet regions. In the range of atomic frequencies (energies), the inelastic collision spectrum is determined from the integrated absorption cross section of X and gamma rays. The resulting spectra will extend the range of applicability of the photoionization model, which is of interest for improving dosimetry planning of the exposure of patients in proton (ion) therapy.