  The General Antiparticle Spectrometer (GAPS) experiment is a novel approach
for the detection of cosmic ray antiparticles. A prototype GAPS experiment
(pGAPS) was successfully flown on a high-altitude balloon in June of 2012. The
goals of the pGAPS experiment were: to test the operation of lithium drifted
silicon (Si(Li)) detectors at balloon altitudes, to validate the thermal model
and cooling concept needed for engineering of a full-size GAPS instrument, and
to characterize cosmic ray and X-ray backgrounds. The instrument was launched
from the Japan Aerospace Exploration Agency's (JAXA) Taiki Aerospace Research
Field in Hokkaido, Japan. The flight lasted a total of 6 hours, with over 3
hours at float altitude (~33 km). Over one million cosmic ray triggers were
recorded and all flight goals were met or exceeded.
