Fragmentation of (158AGeV) Pb ions with Bi target

We have investigated the fragmentation of Pb207 ions at 158AGeV energy in collision with Bi target using CR39 plastic nuclear track detectors. A stack containing CR-39 detectors sandwiched with the target Bi was exposed to (158AGeV)Pb207 ions at SPS beam facility of CERN with a fluence of ∼1500ions/cm2. The detectors were chemically etched and scanned using optical microscope. The data in the form of etched cone height is used for the identification of charge of beam ions and the fragments produced in the charge region 63⩽Z⩽8263⩽Z⩽82. The estimated charge-changing cross sections are significantly higher than those obtained from the geometrical model.