Two-Proton Radioactivity of $^{67}$Kr

T. Goigoux (1) , P. Ascher (1) , Bertram Blank (1) , M. Gerbaux (1) , J. Giovinazzo (1) , S. Grévy (1) , T. Kurtukian Nieto (1) , C. Magron (1) , P. Doornenbal , G.G. Kiss , S. Nishimura , P.A. Söderström , V. H. Phong , J. Wu , D. S. Ahn , N. Fukuda , N. Inabe , T. Kubo , S. Kubono , H. Sakurai , Y. Shimizu , T. Sumikama , H. Suzuki , H. Takeda , J. Agramunt , A. Algora , V. Guadilla , A. Montaner-Piza , A.I. Morales , S.E.A. Orrigo , B. Rubio , Y. Fujita , M. Tanaka , W. Gelletly , P. Aguilera , F. Molina , F. Diel , D. Lubos , G. De Angelis , D. Napoli , C. Borcea , A. Boso , R.B. Cakirli , E. Ganioglu , J. Chiba , D. Nishimura , H. Oikawa , Y. Takei , S. Yagi , K. Wimmer , G. de France (2) , S. Go , B.A. Brown

1 CENBG - Centre d'Etudes Nucléaires de Bordeaux Gradignan
2 GANIL - Grand Accélérateur National d'Ions Lourds

In an experiment with the BigRIPS separator at the RIKEN Nishina Center, we observed two-proton (2p) emission from 67Kr. At the same time, no evidence for 2p emission of 59Ge and 63Se, two other potential candidates for this exotic radioactivity, could be observed. This observation is in line with Q value predictions which pointed to 67Kr as being the best new candidate among the three for two-proton radioactivity. 67Kr is only the fourth 2p ground-state emitter to be observed with a half-life of the order of a few milliseconds. The decay energy was determined to be 1690(17) keV, the 2p emission branching ratio is 37(14)%, and the half-life of 67Kr is 7.4(30) ms.

Domaines: Physique Nucléaire Expérimentale [nucl-ex]

T. Goigoux, P. Ascher, Bertram Blank, M. Gerbaux, J. Giovinazzo, et al.. Two-Proton Radioactivity of $^{67}$Kr. Physical Review Letters, 2016, 117, pp.162501. ⟨10.1103/PhysRevLett.117.162501⟩. ⟨in2p3-01384524⟩