Unveiling the intruder deformed 0${}_2^{+}$ state in ${}^{34}$Si

Abstract

The 0${}_2^{+}$ state in ${}^{34}$Si has been populated at the {\sc Ganil/Lise3} facility through the $\beta$-decay of a newly discovered 1${}^{+}$ isomer in ${}^{34}$Al of 26(1) ms half-life. The simultaneous detection of $e^{+}{e}^{-}$ pairs allowed the determination of the excitation energy E(0${}_2^{+}$)=2719(3) keV and the half-life T${}_{1/2}$=19.4(7) ns, from which an electric monopole strength of ${\rho }^2$(E0)=13.0(0.9)$\times 10^{-3}$ was deduced. The 2${}_1^{+}$ state is observed to decay both to the 0${}_1^{+}$ ground state and to the newly observed 0${}_2^{+}$ state (via a 607(2) keV transition) with a ratio R(2${}_1^{+}$$\to 0_1^{+}/2_1^{+}$$\to 0_2^{+}$)=1380(717). Gathering all information, a weak mixing with the 0${}_1^{+}$ and a large deformation parameter of $\beta$=0.29(4) are found for the 0${}_2^{+}$ state, in good agreement with shell model calculations using a new {\sc sdpf-u-mix} interaction allowing \textit{np-nh} excitations across the N=20 shell gap.

5 pages, 3 figures, accepted for publication in Physical Review Letters

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• Discovery of the shape coexisting 0+ state in 32Mg by a two neutron transfer reaction
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Cited by in corpus (28)

• Evolution of shell structure in exotic nuclei
• The merging of the islands of inversion at N=20 and N=28
• Well-developed deformation in 42Si
• A proton density bubble in the doubly magic ${}^{34}$Si nucleus
• The Neutron-Rich Edge of the Nuclear Landscape. Experiment and Theory
• Ab initio calculation of the potential bubble nucleus ${}^{34}$Si
• Isomer shift and magnetic moment of the long-lived 1/2${}^{+}$ isomer in ${}_{30}^{79}$Zn${}_{49}$: signature of shape coexistence near ${}^{78}$Ni
• Experimental study of the two-body spin-orbit force
• Does a proton "bubble" structure exist in the low-lying states of 34Si?
• Tensor-force effects on single-particle levels and proton bubble structure around the $Z$ or $N=20$ magic number
• Evolution of the N=20 and 28 Shell Gaps and 2-particle-2-hole states in the FSU Interaction
• Shape coexistence in even-even nuclei: A theoretical overview
• Shell evolution and its indication on the isospin dependence of the spin-orbit splitting
• Microsecond Isomer at the N=20 Island of Shape Inversion Observed at FRIB
• Normal and intruder configurations in ${}^{34}$Si populated in the ${\beta }^{-}$ decay of ${}^{34}$Mg and ${}^{34}$Al
• Broken mirror symmetry in ${}^{36}$S and ${}^{36}$Ca
• High-precision quadrupole moment reveals significant intruder component in 33Al20 ground state
• The Structure of ${}^{33}$Si and the magicity of the N=20 gap at Z=14
• Shell Evolutions and Nuclear Forces
• Ab initio nuclear shape coexistence and emergence of island of inversion around $N=20$
• Intruder configurations in ${}^{29}$Ne at the transition into the island of inversion: Detailed structure study of ${}^{28}$Ne
• Spectroscopy of ${}^{28}$Na: shell evolution toward the drip line
• Identifying the spin trapped character of the ${}^{32}$Si isomeric state
• In-beam $\gamma$-ray spectroscopy of ${}^{32}$Mg via direct reactions
• Search for the $1/2^{+}$ intruder state in ${}^{35}$P
• Cross-shell excited configurations in the structure of 34Si
• Existence problem of proton semi-bubble structure in the $2_1^{+}$ state of ${}^{34}$Si
• Coexisting normal and intruder configurations in ${}^{32}$Mg