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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双 MeV 伽马射线和暗物质天文台 - GRAMS 项目

摘要 GRAMS（伽马射线和反物质调查）是一个新颖的项目，可以同时针对 MeV 伽马射线的天体物理观测和反物质的间接暗物质搜索。GRAMS 仪器设计有一个经济高效的大型 LArTPC（液体氩时间投影室）探测器，周围环绕着塑料闪烁体。MeV 能量的天体物理观测尚未得到充分探索（所谓的“MeV 间隙”），与之前的实验相比，GRAMS 可以将灵敏度提高一个数量级以上。在主要关注 MeV 伽马射线观测的同时，GRAMS 还针对宇宙射线反物质调查进行了优化，以间接搜索暗物质。特别是，低能反氘核将提供基本无背景的暗物质特征。