CREAM-Pushing the high energy frontier of directly measured cosmic rays

After nearly a century since their discovery, much is still uncertain about cosmic rays, including their source, acceleration mechanism, and propagation. Direct measurement of cosmic-ray elemental spectra in the critical energy range of 1012–1015 eV offers a promising avenue to answering these questions. The Cosmic Ray Energetics And Mass (CREAM) experiment was launched from McMurdo Station, Antarctica, under a NASA research balloon on December 16, 2004. Floating for nearly 42 days at altitudes between 36 and 39 km, CREAM collected over 4 × 107 events. Preliminary results show great promise for this dataset. CREAM-II launched on December 16, 2005 and ew for 28 days. A refurbished CREAM is planned to y again in 2007. This presentation will examine the experimental context of CREAM, describe the detector, and show preliminary results from accelerator beam tests and the first ight.