Experimental Confirmation of a Scaling Law for the 1sσ Excitation Probability for Z1+Z2+120, and its Breakdown in Pb+Cm Collisions at Very Small Internuclear Distances

Abstract

The excitation probability of the $1s\sigma$-molecular orbital has been measured as a function of the impact parameter $b$ for several collision systems in the region $129<~Z_1+Z_2<~178$ at the UNILAC. All published impact-parameter data agree with a simple scaling law except those for impact parameters $b<~40$ fm in the Pb+Cm system ($Z_1+Z_2=178\mathrm{}$).