Yields of Products withA=100−117in the Interaction of 3- and 28-GeV Protons with Uranium and Lead

Abstract

Cross sections for the formation of 14 isotopes of palladium, cadmium, and indium have been measured for lead and uranium targets bombarded by 3- and 28-GeV protons. The isobaric cross section at $A=109\mathrm{}$ has been determined as 32.2±3.8 mb and 27.2±3.5 mb for uranium at 3 and 28 GeV, respectively, and as 5.8±0.6 mb and 6.9±0.7 mb for lead at the corresponding energies. It is found that the yields of neutron-deficient products increase with energy for both targets by as much as 60-90%. On the other hand, the yields of neutron-excessive products from uranium decrease by 10-30% with increasing energy whereas those from lead show no energy dependence. The yields of neutron-excessive products from uranium are two orders of magnitude larger than those from lead, whereas the neutron-deficient products are formed with slightly larger yields from lead.