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The large reported $E2$ strength between the $2^+$ ground state and $1^+$ first excited state of $^8$Li, $B(E2; 2^+ rightarrow 1^+)= 55(15)$ e$^2$fm$^4$, presents a puzzle. Unlike in neighboring $A=7-9$ isotopes, where enhanced $E2$ strengths may be understood to arise from deformation as rotational in-band transitions, the $2^+rightarrow1^+$ transition in $^8$Li cannot be understood in any simple way as a rotational in-band transition. Moreover, the reported strength exceeds textit{ab initio} predictions by an order of magnitude. In light of this discrepancy, we revisited the Coulomb excitation measurement of this strength, now using particle-$gamma$ coincidences, yielding a revised $B(E2; 2^+ rightarrow 1^+)$ of $25(8)(3)$ e$^2$fm$^4$. We explore how this value compares to what might be expected in rotational, Elliott SU(3), and textit{ab initio} descriptions, including no-core shell model (NCSM) calculations with various internucleon interactions. While the present value is a factor of $2$ smaller than previously reported, it remains anomalously enhanced.
Electromagnetic observables are able to give insight into collective and emergent features in nuclei, including nuclear clustering. These observables also provide strong constraints for ab initio theory, but comparison of these observables between th
Background: Recent developments in {it ab initio} nuclear theory demonstrate promising results in medium- to heavy-mass nuclei. A particular challenge for many of the many-body methodologies, however, is an accurate treatment of the electric-quadrupo
The electric quadrupole transition from the first 2+ state to the ground 0+ state in 16C is studied through measurement of the lifetime by a recoil shadow method applied to inelastically scattered radioactive 16C nuclei. The measured lifetime is 75 +
The lifetimes of the $2^+_1$, the $2^+_2$ and the $3^-_1$ states of $^{210}$Po have been measured in the $^{208}$Pb($^{12}$C,$^{10}$Be)$^{210}$Po transfer reaction by the Doppler-shift attenuation method. The results for the lifetime of the $2^+_1$ s
We observe the electric-dipole forbidden $7srightarrow8s$ transition in the francium isotopes $^{208-211}$Fr and $^{213}$Fr using a two-photon excitation scheme. We collect the atoms online from an accelerator and confine them in a magneto optical tr