Response of Ionization Chambers and Cherenkov Counters to Relativistic Ultraheavy Nuclei

We shall report results from a calibration of a set of high-resolution ionization chambers and Cherenkov counters at the Lawrence Berkeley Laboratory Bevalac, in November 1986. We obtained exposures to beams of 26Fe, 57La, 67Ho, and 79Au, at several diffyfent energies, ranging from -300 MeV/amu to a maximum between 1 and 1.6 Ge V lamu. The detectors were basically similar to those used in the HEA0-3 HNE (Binns et al. 1981) and these exposures were intended to calibrate the response of the HNE detectors to UH nuclei in the cosmic radiation. For nuclei of low .atomic number (Z), the response of these detectors scales like Z2; however, at high Z this scaling is expected to break down (Ahlen 1980,1982; Derrickson et til. 1981).