Stopping power measurements for 100-keV/u Cu ions in hydrogen and nitrogen

A new experimental area has been set up at the RFQ accelerator at ITEP (Moscow) to investigate the interaction of ions with gases and plasmas. The HIPr-ITEP accelerator provides ion beams at a specific energy of 100 keV/u. This energy is particularly suitable for studying the interaction of ions with cold and ionized matter below the maximum of the stopping power. As a first step, the new installation was used to measure the energy loss of copper ions in the nitrogen and hydrogen gases. Equilibrium stopping power values were determined and (as no previous experimental data for the Cu ions below the stopping power maximum existed) compared to the available semiempirical codes SRIM 2000, SRIM 2003, and with the new STIP code based on a clearly defined theoretical model which is now under development at ITEP.