  A high light yield calcium iodide (CaI2) scintillator is being developed for
an astroparticle physics experiments. This paper reports scintillation
performance of calcium iodide (CaI2) crystal. Large light emission of 2.7 times
that of NaI(Tl) and an emission wavelength in good agreement with the sensitive
wavelength of the photomultiplier were obtained. A study of pulse shape
discrimination using alpha and gamma sources was also performed. We confirmed
that CaI2 has excellent pulse shape discrimination potential with a quick
analysis.
