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arXiv · 1901.03430

Dual MeV Gamma-Ray and Dark Matter Observatory -- GRAMS Project

Tsuguo Aramaki·Per Hansson Adrian·Georgia Karagiorgi·Hirokazu Odaka
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Abstract

GRAMS (Gamma-Ray and AntiMatter Survey) is a novel project that can simultaneously target both astrophysical observations with MeV gamma rays and an indirect dark matter search with antimatter. The GRAMS instrument is designed with a cost-effective, large-scale LArTPC (Liquid Argon Time Projection Chamber) detector surrounded by plastic scintillators. The astrophysical observations at MeV energies have not yet been well-explored (the so-called "MeV-gap") and GRAMS can improve the sensitivity by more than an order of magnitude compared to previous experiments. While primarily focusing on MeV gamma-ray observations, GRAMS is also optimized for cosmic ray antimatter surveys to indirectly search for dark matter. In particular, low-energy antideuterons will provide an essentially background-free dark matter signature. GRAMS will be a next generation experiment beyond the current GAPS (General AntiParticle Spectrometer) project for antimatter survey.

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Tsuguo Aramaki, Per Hansson Adrian, Georgia Karagiorgi, Hirokazu Odaka. 2019-12-05. Dual MeV Gamma-Ray and Dark Matter Observatory -- GRAMS Project. https://doi.org/10.1016/j.astropartphys.2019.07.002

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