A transverse beam profile monitor that visualizes a two-dimensional beam-induced fluorescent image was developed. The monitor employs a sheet-shaped gas flow formed by a technique of rarefied gas dynamics. A simplified analysis method was developed to reconstruct the beam intensity profile from the obtained image. The developed profile monitor and the analysis method were applied to measure the J-PARC 3 MeV ${\mathrm{H}}^{-}$ beam profile. The root mean square values of the profiles were consistent with the ones obtained by a wire-scanning-type beam profile monitor. The beam loss due to the gas sheet injection was measured as a beam-current reduction. The amount of the beam current decreased in proportion to the gas sheet flux and the reduction ranged from 0.004 to 2.5%. The assembled system was capable of reconstructing a beam profile from a single shot beam pulse ($1.7\times {10}^{13}$ protons in $50\mu \mathrm{s}$).

中文翻译：

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使用气体薄片监测器通过束诱导荧光检测进行高强度束轮廓测量

开发了可视化二维光束感应荧光图像的横向光束轮廓监视器。监控器采用通过稀有气体动力学技术形成的片状气流。开发了一种简化的分析方法，用于根据获得的图像重建光束强度轮廓。研发的轮廓监测仪和分析方法被用于测量J-PARC 3 MeV${\mathrm{H}}^{-}$光束轮廓。轮廓的均方根值与通过线扫描型光束轮廓监视器获得的均方根值一致。测量由于气体薄板注入而引起的束损失，作为束电流减少量。束电流的量与气体薄板通量成比例地减小，并且减小的范围为0.004至2.5％。组装后的系统能够从单次发射光束脉冲中重建光束轮廓（$1.7\times {10}^{13}$ 质子 $50\mu \mathrm{s}$）。