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First direct observation of two protons in the decay of $^{45}$Fe with a TPC

J. Giovinazzo·B. Blank·C. Borcea·G. Canchel·C. E. Demonchy·F. de Oliveira Santos·C. Dossat·S. Grevy·L. Hay·J. Huikari·S. Leblanc·I. Matea·J. -L. Pedroza·L. Perrot·J. Pibernat·L. Serani·C. Stodel·J. -C. Thomas
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Abstract

The decay of the ground-state two-proton emitter 45Fe was studied with a time-projection chamber and the emission of two protons was unambiguously identified. The total decay energy and the half-life measured in this work agree with the results from previous experiments. The present result constitutes the first direct observation of the individual protons in the two-proton decay of a long-lived ground-state emitter. In parallel, we identified for the first time directly two-proton emission from 43Cr, a known beta-delayed two-proton emitter. The technique developped in the present work opens the way to a detailed study of the mechanism of ground-state as well as beta-delayed two-proton radioactivity.

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J. Giovinazzo, B. Blank, C. Borcea, G. Canchel, C. E. Demonchy, F. de Oliveira Santos, C. Dossat, S. Grevy, L. Hay, J. Huikari, S. Leblanc, I. Matea, J. -L. Pedroza, L. Perrot, J. Pibernat, L. Serani, C. Stodel, J. -C. Thomas. 2007-03-05. First direct observation of two protons in the decay of $^{45}$Fe with a TPC. https://doi.org/10.1103/physrevlett.99.102501

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