Results from an Antarctic Balloon Flight

Two balloon-borne 30x40 cm2 JACEE emulsion chamber modules were exposed in Antarctica for 204 hours at 3.9 g/cm2 average overburden in December, 1990. This flight functioned as both an independent data sample and as a feasibility test for subsequent Antarctic long duration ballon flights (LDBF). New, highly efficient analysis methods were developed and tested. Proton and helium spectra obtained from this flight alone are consistent in both absolute flux and spectral index with previously-published data, and the results demonstrate the value of Polar LDBF for spectral studies of this type.