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Further search for a neutral boson with a mass around 9 MeV/c2

F. W. N. de Boer·K. Bethge·H. Bokemeyer·R. van Dantzig·J. van Klinken·V. Mironov·K. A. Mueller·K. E. Stiebing
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Abstract

Two dedicated experiments on internal pair conversion (IPC) of isoscalar M1 transitions were carried out in order to test a 9 MeV/c2 X-boson scenario. In the 7Li(p,e+e-)8Be reaction at 1.1 MeV proton energy to the predominantly T=0 level at 18.15 MeV, a significant deviation from IPC was observed at large pair correlation angles. In the 11B(d,n e+e-)12C reaction at 1.6 MeV, leading to the 12.71 MeV 1+ level with pure T=0 character, an anomaly was observed at 9 MeV/c2. The compatibility of the results with the scenario is discussed.

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F. W. N. de Boer, K. Bethge, H. Bokemeyer, R. van Dantzig, J. van Klinken, V. Mironov, K. A. Mueller, K. E. Stiebing. 2001-02-28. Further search for a neutral boson with a mass around 9 MeV/c2. https://doi.org/10.1088/0954-3899%2F27%2F4%2F102

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