Jw. Norbury et G. Baur, EXPLANATION OF RECENT OBSERVATIONS OF VERY LARGE ELECTROMAGNETIC DISSOCIATION CROSS-SECTIONS .2. HIGHER-ORDER CORRECTIONS, Physical review. C. Nuclear physics, 48(4), 1993, pp. 1915-1918
Hill, Wohn, Schwellenbach, and Smith have recently measured very large
electromagnetic dissociation cross sections in the collisions of very
heavy nuclei. Weizsacker-Williams (WW) theory predicts that these cro
ss sections should be even larger. It has recently been shown that WW
theory fails for these reactions because the associated probabilities
are too large. However, WW theory is based on first order perturbation
theory and an electric dipole approximation. Calculations are present
ed which show that for those cases where WW theory and experiment disa
gree, higher order perturbation plus electric quadrupole corrections i
mprove the agreement between theory and experiment. These corrections
also imply that multiple electromagnetic excitations occur.