Electromagnetic Dissociation of Target Nuclei by $^{208}$Pb Projectiles

% NA53 \\ \\ The purpose of this experiment is to study the process of electromagnetic dissociation (ED) that occurs at impact parameters large enough so that there is no nuclear interaction. In these cases strong electromagnetic fields are produced for a short time at the nucleus. For large charges and ultrarelativistic energies, the intense electromagnetic pulse produces cross-sections much larger than the total hadronic cross-section. These effects place significant constraints on the storage times of the heavy ion beams planned for RHIC and LHC.\\ \\In this experiment we measure the cross-sections for the one- and two-neutron removal processes resulting from the interaction of 160 and 40~GeV/nucleon Pb beams on Au and Co targets. Thin Au targets were bombarded in the beam line of the NA50 experiment. Gamma rays from the residual nuclides produced in the bombardment were measured to determine the saturation activities of $^{196}$Au and $^{195}$Au resulting from ED of the Au target. This along with cross-sections for deep spallation products will enable us to determine ED cross-sections for one- and two-neutron reactions from Au. Additional bombardments using Co targets enable us to observe large ED effects in a low Z target. Bombardments at 160 GeV/nucleon have been completed and data analysis is in progress. Bombardments at 40 GeV/nucleon on Au and Co targets will take place in fall 1999.\\ \\