We performed an experiment using plastic nuclear track detectors to investigate the phenomenon of enlarged cross sections for projectile fragments of relativistic ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ar}$ nuclei. This effect had been observed within the first few centimeters after fragment emission in Bevalac and cosmic-ray experiments with nuclear emulsion. On the basis of 6444 charge-changing nuclear collisions we conclude that under our experimental conditions no statistically significant anomalous mean free path effect can be observed.

• Received 27 December 1983

DOI:https://doi.org/10.1103/PhysRevLett.52.1401