An accelerator test of semi-empirical cross-sections

Experimentally measured yields of isotopes of elements from Mg-12 to K-19 resulting from the fragmentation of Ar-40 are compared with calculated yields based on semiempirical cross-section formulae. The measurements, made at the LBL Bevalac using a beam of 287 MeV/amu Ar-40 incident on a CH2 target, achieve excellent mass resolution (up to 0.2 amu) through the use of a Si(Li) detector telescope. The general agreement between calculation and experiment is good (rms difference of about 24 percent), but some significant differences are reported.