Measurement of the Deuterium Flux in the Kinetic Energy Range 12-22 GeV/n with the CAPRICE98 Experiment

摘要

The balloon-borne CAPRICE98 instrument was flown on 28-29 May 1998 from Fort Sumner,New Mexico,USA.The detector configuration included the NMSU-WiZard/CAPRICE magnetic spectrometer equipped with a gas ring imaging Cherenkov detector(RICH),a silicon-tungsten calorimeter and a time-of-flight system.Deuterons were identified by using the RICH as a threshold device.This allowed for the first measurement of the deuterium flux at kinetic energies above 2 GeV/n.We report the results on the energy spectrum of the primary cosmic-ray deuterons and on the deuteron to helium ratio between 12 GeV/n and 22 GeV/n.The CAPRICE98 balloon-borne experiment(Cosmic AntiParticle Ring Imaging Cherenkov Experiment,1998)is the latest detector built and flown by the WiZard collaboration.The instrument configuration allowed several science objectives to be achieved,among which is the measurement of the ~2H abundance.