Shape changes in the mirror nuclei ${}^{70}$Kr and ${}^{70}$Se

Abstract

We studied the proton-rich $T_z=-1$ nucleus ${}^{70}$Kr through inelastic scattering at intermediate energies in order to extract the reduced transition probability, $B(E2;0^{+}\to 2^{+})$. Comparison with the other members of the $A=70$ isospin triplet, ${}^{70}$Br and ${}^{70}$Se, studied in the same experiment, shows a $3\sigma$ deviation from the expected linearity of the electromagnetic matrix elements as a function of $T_z$. At present, no established nuclear structure theory can describe this observed deviation quantitatively. This is the first violation of isospin symmetry at this level observed in the transition matrix elements. A heuristic approach may explain the anomaly by a shape change between the mirror nuclei ${}^{70}$Kr and ${}^{70}$Se contrary to the model predictions.

arXiv commentaccepted PRL

References in corpus (12)

• Nuclear ground-state masses and deformations: FRDM(2012)
• New effective interaction for $pf$-shell nuclei and its implications for the stability of the $N$=$Z$=28 closed core
• Structure of even-even nuclei using a mapped collective Hamiltonian and the D1S Gogny interaction
• DALI2: A NaI(Tl) detector array for measurements of $\gamma$ rays from fast nuclei
• Isobaric multiplet yrast energies and isospin non-conserving forces
• Charge Symmetry Breaking and QCD
• Structure of Krypton isotopes calculated with symmetry conserving configuration mixing methods
• Global optical potential for nucleus-nucleus systems from 50 MeV/u to 400 MeV/u
• Observation of mutually enhanced collectivity in self-conjugate ${}_{38}^{76}$Sr${}_{38}$
• Coulomb shifts and shape changes in the mass 70 region
• Shape coexistence revealed in the $N=Z$ isotope ${}^{72}$Kr through inelastic scattering
• Shape coexistence and isospin symmetry in $A=70$ nuclei: Spectroscopy of the $T_z=-1$ nucleus ${}^{70}$Kr

Cited by in corpus (12)

• Shape coexistence in even-even nuclei: A theoretical overview
• Information content of the differences in the charge radii of mirror nuclei
• The structure of ${}^{36}$Ca under the Coulomb magnifying glass
• Shell model analysis of the $B(E2,2^{+}\to 0^{+})$'s in the A=70 T=1 triplet
• Investigation of octupole collectivity near the $A=72$ shape-transitional point
• The $\beta$-decay properties of $N=Z$ nuclei: Role of neutron-proton pairing and the shell model interpretation
• Improved measurement of the $0_2^{+}\to 0_1^{+}$ E0 transition strength for ${}^{72}$Se using the SPICE spectrometer
• Quadrupole Strength in Isobaric Triplets
• Mirror-skin thickness: a possible observable sensitive to the charge symmetry breaking energy density functional
• Investigation of the determination of nuclear deformation using high-energy heavy-ion scattering
• Proton removal from ${}^{73,75}$Br to ${}^{72,74}$Se at intermediate energies
• Ab initio study of $\beta$-decay and pairing in $N=Z$ nuclei