Stopping powers of a tissue-equivalent gas for 40-200 ke V He+ and N+

The stopping powers of a tissue-equivalent gas have been measured for He+ and N+ using the ion beams from a Cockcroft and Walton type accelerator and a differentially pumped gas cell. The stopping powers of each component of the tissue-equivalent gas were also measured and used to calculate expected values of the stopping powers of the tissue-equivalent gas. Results from direct measurement and from calculation showed good agreement.