Range-Energy Relations for Helium Ions and Protons in Ar,N2,O2, and Air (0.2-2.0 MeV)

Abstract

The ionization extrapolated ranges of ${\mathrm{H}}^{+}$ and ${\mathrm{He}}^{+}$ in Ar, ${\mathrm{N}}_2$, ${\mathrm{O}}_2$, and air have been measured from 200 keV to 2.0 MeV with an accuracy of ± 1%. A magnetically analyzed beam of ions was brought through a differential pumping system into a gas stopping cell. A single-grid ionization chamber, movable parallel to the beam axis, was used to obtain the data necessary to plot a Bragg curve. The observed range-energy relations are compared with previous data where possible.