We report on the results of the first search for the production of axion-like particles (ALPs) via Primakoff production on nuclear targets, , in the “SRC-CT” experiment using the GlueX detector at Jefferson Lab. This search uses an integrated luminosity of 100 pbnucleon on a C target with a real photon beam of energies GeV, and explores the mass region of MeV via the decay . This mass range is between the and meson masses, which enables the use of the measured meson production rate to obtain absolute bounds on the ALP production with reduced sensitivity to experimental luminosity and detection efficiency. We find no evidence for an ALP, consistent with previous searches in the quoted mass range, and present limits on the effective photon coupling scale of . We further find that the ALP production limit we obtain is hindered by the peaking structure of the non-target-related dominant background the in GlueX spectrometer, which we treat by using data on He to estimate and subtract it. We comment on how this search can be improved in a future higher-statistics dedicated measurement.

中文翻译：

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使用 GlueX 探测器通过核 Primakoff 生产寻找轴子状粒子


我们报告了在杰斐逊实验室使用 GlueX 探测器进行的“SRC-CT”实验中，首次通过 Primakoff 在核靶上生产来寻找类轴子粒子 (ALP) 生产的结果。该搜索使用 C 目标上 100 pb 核子的积分光度和能量为 GeV 的真实光子束，并通过衰变探索 MeV 的质量区域。该质量范围介于介子质量和介子质量之间，这使得能够使用测量的介子产生速率来获得 ALP 产生的绝对界限，同时降低对实验光度和检测效率的敏感性。我们没有发现 ALP 的证据，与之前在引用的质量范围内的搜索一致，并且对有效光子耦合尺度提出了限制。我们进一步发现，我们获得的 ALP 产量限制受到 GlueX 光谱仪中与目标无关的主导背景的峰化结构的阻碍，我们通过使用 He 数据来估计和减去它来处理它。我们评论了如何在未来更高统计量的专用测量中改进此搜索。