Laser-assisted charge exchange (LACE) is a novel scheme for injecting $H^{-}$ ions into proton rings. Lorentz stripping of $H^{-}$ ions into bare protons in magnetic dipoles is enabled by laser excitation that reduces the electron binding energy. We show that such atomic transitions impose very precise requirements on ion and laser parameters which can be utilized to measure the ion velocity. At the LACE experimental station at the Spallation Neutron Source (SNS), proton beam energy has been measured via LACE to a precision of $<1\mathrm{MeV}$ for a $\approx 1\mathrm{GeV}$ beam. To verify the results against the existing energy measurement method at the SNS which calculates revolution frequency in the accumulator ring, we discuss how knowledge of the beam energy can be employed to synchronize phase probes. Such beam-based calibration using energy measurements via both LACE and the SNS ring show that the two methods produce consistent results.

中文翻译：

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激光辅助电荷交换作为质子束能量测量和相位探针校准的原子尺度

激光辅助电荷交换（LACE）是一种新颖的注入方案 $H^{-}$离子进入质子环。洛伦兹剥离$H^{-}$激光激发降低了电子结合能，从而使离子变成了磁偶极子中的裸质子。我们表明，这种原子跃迁对离子和激光参数提出了非常精确的要求，这些参数可用于测量离子速度。在散裂中子源（SNS）的LACE实验站，已通过LACE测量了质子束能量，其精度为$<\mathrm{1个}\mathrm{电动汽车}$ 为一个 $\approx \mathrm{1个}\mathrm{GeV}$光束。为了对照现有的SNS处的能量测量方法（可计算累加器环中的旋转频率）验证结果，我们讨论了如何利用光束能量的知识来同步相位探测器。这种使用基于LACE和SNS环的能量测量进行的基于波束的校准表明，这两种方法可产生一致的结果。