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arXiv · 1612.05868

Decay mechanism and lifetime of $^{67}$Kr

L. V. Grigorenko·T. A. Golubkova·J. S. Vaagen·M. V. Zhukov
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Abstract

The lifetime of the recently discovered $2p$ emitter $^{67}$Kr was recently found considerably below the lower limit predicted theoretically. This communication addresses this issue.Different separation energy systematics are analyzed and different mechanisms for $2p$ emission are evaluated. It is found that the most plausible reason for this disagreement is a decay mechanism of $^{67}$Kr, which is not "true $2p$" emission, but "transition dynamics" on the borderline between true $2p$ and sequential $2p$ decay mechanisms. If this is true, this imposes stringent limits $E_r=1.35-1.42$ MeV on the ground state energy of $^{66}$Br relative to the $^{65}$Se-$p$ threshold.

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L. V. Grigorenko, T. A. Golubkova, J. S. Vaagen, M. V. Zhukov. 2016-12-18. Decay mechanism and lifetime of $^{67}$Kr. https://doi.org/10.1103/physrevc.95.021601

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