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arXiv · 1907.00114

Direct observation of proton emission in 11Be

Y. Ayyad·B. Olaizola·W. Mittig·G. Potel·V. Zelevinsky·M. Horoi·S. Beceiro-Novo·M. Alcorta·C. Andreoiu·T. Ahn·M. Anholm·L. Atar·A. Babu·D. Bazin·N. Bernier·S. S. Bhattacharjee·M. Bowry·R. Caballero-Folch·M. Cortesi·C. Dalitz·E. Dunling·A. B. Garnsworthy·M. Holl·B. Kootte·K. G. Leach·J. S. Randhawa·Y. Saito·C. Santamaria·P. Šiuryte·C. E. Svensson·R. Umashankar·N. Watwood·D. Yates
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Abstract

The elusive $\beta^-\text{p}^+$ decay was observed in $^{11}$Be by directly measuring the emitted protons and their energy distribution for the first time with the prototype Active Target Time Projection Chamber (pAT-TPC) in an experiment performed at ISAC-TRIUMF. The measured $\beta^-\text{p}^+$ branching ratio is orders of magnitude larger than any previous theoretical model predicted. This can be explained by the presence of a narrow resonance in $^{11}$B above the proton separation energy.

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Y. Ayyad, B. Olaizola, W. Mittig, G. Potel, V. Zelevinsky, M. Horoi, S. Beceiro-Novo, M. Alcorta, C. Andreoiu, T. Ahn, M. Anholm, L. Atar, A. Babu, D. Bazin, N. Bernier, S. S. Bhattacharjee, M. Bowry, R. Caballero-Folch, M. Cortesi, C. Dalitz, E. Dunling, A. B. Garnsworthy, M. Holl, B. Kootte, K. G. Leach, J. S. Randhawa, Y. Saito, C. Santamaria, P. Šiuryte, C. E. Svensson, R. Umashankar, N. Watwood, D. Yates. 2019-06-28. Direct observation of proton emission in 11Be. https://doi.org/10.1103/physrevlett.123.082501

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