The Cosmic Ray Energetics And Mass (CREAM) instrument

The Cosmic Ray Energetics And Mass (CREAM) experiment is designed to investigate high-energy (1012∼1015 eV) cosmic rays over the elemental range from hydrogen to iron (1⩽Z⩽26), through a series of long balloon flights. Originally planned to be flown on the first of the new Ultra Long Duration Balloons (ULDB) being developed by NASA, the CREAM instrument was launched as a Long Duration Balloon (LDB) payload from McMurdo Station, Antarctica on December 16, 2004 and flew for a record-breaking 42 days. A second CREAM flight one year later lasted 28 days. The CREAM design is unique in that it obtains two independent energy measurements using a tungsten/scintillator sampling calorimeter and a Transition Radiation Detector (TRD) with up to four independent charge measurements of incident particles using a novel Timing-based scintillator Charge Detector (TCD), a plastic Cherenkov Detector (CD), scintillating fiber hodoscopes, and a Silicon Charge Detector (SCD). The energy limits are determined by trigger efficiency and telemetry bandwidth at the low end and by statistics at the high end.