High-resolution X-ray spectroscopy of the highly charged muonic atoms/ions isolated in vacuum is an ideal probe to explore quantum electrodynamics under extremely strong electric fields, which is one of the major topic in fundamental atomic physics. A feasibility test measurement with a low-density neon gas target was performed by observing X-rays emitted by muonic neon via the $$5 \rightarrow 4$$ transition, $$\sim$$ 6.3 keV, using a multi-pixel array of superconducting transition-edge-sensor (TES) microcalorimeters at the J-PARC muon facility. We successfully demonstrated the feasibility of muonic atom X-ray spectroscopy with a gas target at a pressure as low as 0.1 atom using TES array under an intense pulsed muon beam.

中文翻译：

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使用过渡边缘传感器在真空中隔离的 μ 原子的 X 射线光谱

在真空中隔离的高电荷μ子原子/离子的高分辨率X射线光谱是探索极强电场下量子电动力学的理想探针，这是基础原子物理学的主要课题之一。对低密度氖气目标的可行性测试测量是通过观察μ子氖通过 $5\rightarrow 4$$ 跃迁、$$\sim$$ 6.3 keV 发射的 X 射线进行的，使用多像素阵列J-PARC μ 子设施中的超导过渡边缘传感器 (TES) 微量热仪。我们在强脉冲μ子束下使用TES阵列成功证明了μ子原子X射线光谱在压力低至0.1原子的气体目标下的可行性。