Abstract
The Japanese American Cooperative Emulsion Experiments (JACEE) have recently carried out a series of Antarctic circumpolar long duration balloon flights (JACEE-10 - JACEE-13) for the study of high energy elemental composition and energy spectra of cosmic ray particles. The total exposure factor of these experments is 663 m2hr, which corresponds to about twice the cumulative exposure from JACEE-1 to JACEE-8. The preliminary result of JACEE-12 analysis shows 8, 5, 4 events for charge groups, C-O, Ne-S, and Z >= 17, respectively, above the selection energy of Sigma E Gamma approximately 20 TeV.
