K-vacancy production in heavy-ion-atom collisions at small impact parameters

The probability P(b) of forming K vacancies in 60-MeV I + Ag collisions with center-of-mass scattering angles theta /SUB cm/ between 200 and 1440 was measured. The measured probability varies approximately as sin2theta /SUB cm/ , as predicted for the kinematic peak part of 2psigma-2pπ rotatational coupling. The authors conclude that while the shape of P(b) indicates that 2psigma-2pπ rotational coupling is important in the creation of K vacancies, the probability of creating the initial 2pπ vacancy must be impact parameter dependent. In other collisions where a rise in P(b) has been observed at low impact parameters, it is possible that the rise is due not to a kinematic peak, but to a contribution from lssigma vacancy production