EXPERIMENTAL-STUDY OF STOPPING POWER FOR HIGH-Z ION IN HYDROGEN

The stopping power of iodine ions traversing a windowless hydrogen tar get has been measured varying the gas in a large pressure range (10(-1 )-120 Torr). Experimental measurements present the energy losses and t he charge distributions of emerging ions. Incident energies of iodine ion beams correspond to a domain where high-velocity approximation is valid. Stopping range extends up to 70% of the incident energy. Those results enable us to test stopping power theories at high velocity and large perturbation parameter Z/V. Higher-order correction terms for t he stopping, calculated with point-like approximation for the charge o r with more realistic atomic potential are compared with experimental energy losses. (C) 1998 Elsevier Science B.V. All rights reserved.