The Super-TIGER Instrument to Probe Galactic Cosmic-Ray Origins*

Super-TIGER is a large area (5.4 m$^2$) balloon-borne instrument designed to measure ultra-heavy cosmic-ray nuclei (Z = 30 and above) with individual-element resolution and high statistical precision. These measurements will provide sensitive tests of the emerging model of cosmic-ray origins in OB associations and models of the mechanism for selection of nuclei for acceleration. Furthermore, Super-TIGER will measure the energy spectra of the more abundant elements in the interval 10 $\le Z \le$ 28 at energies 0.8 $<$ E $<$ 10 GeV/nucleon to test the hypothesis that microquasars or other sources could superpose spectral features. Super-TIGER, which builds on the heritage of the smaller TIGER, is expected to launch from Antarctica in December 2012. The particle charge and energy will be measured with a combination of plastic scintillators, acrylic and silica-aerogel Cherenkov detectors, and a scintillating fiber hodoscope. The design, expected performance and current status of the instrument along with the scientific implications of the Super-TIGER measurements will be presented.