Total interaction and proton-removal cross-section measurements for the proton-rich isotopes 7Be, 8B, and 9C

Abstract

In an experiment performed at the FRS of GSI, we measured total interaction cross sections for 7Be, 8B, and 9C, one-proton-removal cross sections for 8B and 9C as well as two-proton-removal cross sections for 9C on targets ranging from carbon to lead at an energy of 285 MeV/nucleon. In addition, we performed measurements at 142 MeV/nucleon for 8B. The experimental results are compared to different calculations. Glauber-type calculations with different model·density distributions show that, down to incident energies of about 50 MeV/nucleon, total interaction cross-section measurements with light targets are not sensitive to an extended proton distribution in 8B. However, at lower incident energies, a tail in the proton density distribution is needed to explain the total interaction cross sections. Total interaction cross-section measurements with high-Z targets in the present experiment show a significant increase of the cross sections due to low-lying electromagnetic strength.