An active fission target has been developed for the FIPPS instrument at ILL, enabling for the first time an efficient suppression of \(\upbeta \)-delayed \(\upgamma \) rays in high-resolution and high-efficiency \(\upgamma \)-ray spectroscopy of fission fragments at a neutron beam. The target is based on a liquid scintillator in which the actinide is dissolved, resulting in a 4\(\pi \) fragment detection. Measurements have been performed with \(^{233, 235}\)U, with a fission tagging efficiency of 97.8(25)%. The high efficiency, together with the good time resolution of the scintillator target, provide high-selectivity data for \(\upgamma \)-ray spectroscopy studies of fission fragments.

中文翻译：

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基于液体闪烁体的FIPPS主动裂变靶标的研制

活性裂变目标已经在ILL的FIPPS仪器被开发出来，使得能够首次的有效抑制\（\ upbeta \） -delayed \（\ upgamma \）在高分辨率和高效率的射线\（\ upgamma \）-中子束裂变碎片的射线光谱。目标基于溶解sc系元素的液体闪烁体，从而检测到4 \（\ pi \）碎片。已使用\（^ {233，235} \） U进行了测量，裂变标记效率为97.8（25）％。高效的闪烁体目标具有良好的时间分辨率，可为\（\ upgamma \）提供高选择性数据射线光谱学研究裂变碎片。