https://doi.org/10.1051/epjconf/202328007002
The GAPS experiment: Low-energy antinuclei measurements for dark matter searches
1
INFN, Sezione di Trieste,
Padriciano 99,
I-34149
Trieste, Italy
2
Full author list: https://gaps1.astro.ucla.edu/gaps/authors/
* e-mail: nadir.marcelli@ts.infn.it
Published online: 20 March 2023
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. 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 experiment will conduct a series of at least three long-duration balloon flights at high altitudes from Antarctica. 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 within the order of nanoseconds 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.
© The Authors, published by EDP Sciences, 2023
This is an Open Access article distributed under the terms of the Creative Commons Attribution License 4.0 (http://creativecommons.org/licenses/by/4.0/).
