A New Measurement of the Energy Spectra of Heavy Cosmic-Ray Nuclei up to Very High Energies

The TRACER cosmic-ray detector was exposed in a long-duration balloon flight from McMurdo, Antarctica in December 2003. The instrument, with a geometric factor of $\sim$ 5 m$^2$ ster, performed well and provided measurements for a duration of ten days with zero dead-time. TRACER measured the energy of cosmic ray nuclei at single charge resolution over the range oxygen to iron (8 $\leq$ Z $\leq$ 26). We shall present preliminary results on the energy spectra of these nuclei from $\sim$ 500 MeV/nucleon to $\sim$ 10 TeV/nucleon. The data will be compared with results from previous measurements, and discussed in the context of current models on the galactic propagation of cosmic rays.