Speaker
Description
GAPS (General Anti-Particle Spectrometer) is a balloon-borne experiment designed to measure low-energy (< 0.25 GeV/n) cosmic antinuclei (i.e., antiprotons, antideuterons, and antihelium nuclei) as a signature of dark matter annihilation or decay. The experiment will conduct a series of long-duration balloon flights at high altitudes from Antarctica. According to viable beyond-the-Standard Model theories, the predicted dark matter signal in the low-energy antideuterons and antihelium nuclei channels is several orders of magnitude higher than the astrophysical background. The instrument is composed of a Si(Li) tracker surrounded by a Time-of-Flight system made of plastic scintillators. GAPS uses the novel exotic-atom detection technique in which an antinucleus is captured by the tracker material and forms an exotic atom. This excited exotic atom decays emitting X-rays at specific energies defined by the atomic transitions and annihilates emitting secondary particles (mainly pions and protons). The measured quantities (e.g., dE/dx, time of flight, annihilation vertex position, X-rays energies, etc.) allow for identifying antinuclei with high precision. This talk will briefly review the theoretical implications behind the experiment and report on the construction and performance status of the GAPS instrument.
