We report on an attempt to reproduce the observation of \(\beta ^-\)-delayed proton emission from \(^{11}\)Be through detection of the final state nucleus \(^{10}\)Be with accelerator mass spectrometry. Twelve samples were collected at the ISOLDE facility at CERN at different separator settings, allowing tests of different sources of contamination to be carried out. The observed amounts of \(^{10}\)Be per collected \(^{11}\)Be rule out several contamination sources, but do not agree internally. Formation of BeH molecular ions in the ion source may explain our data, in which case an upper limit of the \(\beta \)p branching ratio of \(2.2 \times 10^{-6}\) can be derived.

中文翻译：

---

从$$ ^ {11} $$ 11 Be中搜索β延迟质子发射

我们在试图重现的观察报告- \（\ \测试^） -delayed质子从发射\（^ {11} \）要通过检测的最终状态核\（^ {10} \）要与加速器质谱。在CERN的ISOLDE工厂以不同的分离器设置收集了十二个样品，从而可以测试不同的污染源。所观察到的\（^ {10} \）数量应为每个收集的\（^ {11} \）。排除几种污染源，但内部意见不一致。离子源中BeH分子离子的形成可能解释了我们的数据，在这种情况下，\（\ beta \） p支化比的上限为\（2.2 \乘以10 ^ {-6} \） 可以得出。