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arXiv · 2405.01276

Detailed study of the decay of $^{21}$Mg

E. A. M. Jensen·S. T. Nielsen·A. Andreyev·M. J. G. Borge·J. Cederkäll·L. M. Fraile·H. O. U. Fynbo·L. J. Harkness-Brennan·B. Jonson·D. S. Judson·O. S. Kirsebom·R. Lică·M. V. Lund·M. Madurga·N. Marginean·C. Mihai·R. D. Page·Á. Perea·K. Riisager·O. Tengblad
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Abstract

Beta-delayed proton and gamma emission in the decay of $^{21}$Mg has been measured at ISOLDE, CERN with the ISOLDE Decay Station (IDS) set-up. The existing decay scheme is updated, in particular what concerns proton transitions to excited states in $^{20}$Ne. Signatures of interference in several parts of the spectrum are used to settle spin and parity assignments to highly excited states in $^{21}$Na. The previously reported $\beta$p$\alpha$ branch is confirmed. A half-life of 120.5(4) ms is extracted for $^{21}$Mg. The revised decay scheme is employed to test mirror symmetry in the decay and to extract the beta strength distribution of $^{21}$Mg that is compared with theory.

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E. A. M. Jensen, S. T. Nielsen, A. Andreyev, M. J. G. Borge, J. Cederkäll, L. M. Fraile, H. O. U. Fynbo, L. J. Harkness-Brennan, B. Jonson, D. S. Judson, O. S. Kirsebom, R. Lică, M. V. Lund, M. Madurga, N. Marginean, C. Mihai, R. D. Page, Á. Perea, K. Riisager, O. Tengblad. 2024-05-02. Detailed study of the decay of $^{21}$Mg. https://doi.org/10.1140/epja/s10050-024-01376-6

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