Performance in flight of the CREAM-III and CREAM-IV calorimeters

The Cosmic Ray Energetic And Mass (CREAM) balloon-borne experiment is designed to investigate the composition and energy of cosmicray nuclei. From December 2007 to January 2008 and again from December 2008 to January 2009, CREAM flew on its third and fourth flights from McMurdo, Antarctica. The payload includes a full suite of instruments, including a calorimeter constructed of 20 layers of 1 radiation-length thick tungsten plates interleaved with 20 layers of 0.5 mm diameter scintillating fiber ribbons, and used to measure the elemental energy spectra of cosmic rays up to 10 eV. Improved calorimeter front-end readout electronics were introduced to reduce noise levels, and the data indicate good performance. In this paper we present the performance in flight of the CREAM-III and CREAM-IV calorimeters, including a preliminary distribution of deposited energy.