The nuclear track detector CR39 was calibrated with different ions of different energies. Due to the low detection threshold (Z/beta~6e) and the good charge resolution (sigma_Z ~ 0.2e for 6e < Z/beta <83e with 2 measurements), the detector was used f
or different purposes: (i) fragmentation of high and medium energy ions; (ii) search for magnetic monopoles, nuclearites, strangelets and Q-balls in the cosmic radiation.
New measurements of the total and partial fragmentation cross sections in the energy range 0.3-10 A GeV of Fe^{26+}, Si^{14+} and C^{6+} beams on polyethylene, CR39 and aluminum targets are presented. The exposures were made at Brookhaven National La
boratory (BNL), USA, and Heavy Ion Medical Accelerator in Chiba (HIMAC), Japan. The CR39 nuclear track detectors were used to identify the incident and survived beams and their fragments. The total fragmentation cross sections for all targets are almost energy independent while they depend on the target mass. The measured partial fragmentation cross sections are also discussed.
