Measurement of the $B(E2; 2^+ \rightarrow 1^+)$ of $^8$Li and comparisons to \textit{ab initio} calculations

Precise measurements of electromagnetic transition strengths in light nuclei can provide stringent tests of nuclear \textit{ab initio} calculations. In the A=7 isobars, specifically $^7$Li and $^7$Be, the B(E2) transition strengths have been used to benchmark different \textit{ab initio} calculations [S.~L.~Henderson \textit{et al.}, Phys.\ Rev.\ C \textbf{99}, 064320 (2019)]. We will continue testing by extending these measurements into the A=8 region and measure the first excited state in $^8$Li, in order to provide additional constraints to these \textit{ab initio} models. These models can give us insight into the structural changes from $^7$Li to $^8$Li due to the addition of a neutron. We have performed a Coulomb excitation experiment to measure the $B(E2; 2+ \rightarrow 1+)$ transition strength in $^8$Li. The $^8$Li was produced and separated with TwinSol and the Coulomb excitation cross section was measured using particle-gamma coincidences. The preliminary B(E2) value will be presented and compared to \textit{ab initio} calculations for $^8$Li, highlighting the structural evolution in Li isotopes due to higher neutron excess. The results of this experiment will also provide a test of the accuracy of available \textit{ab initio} calculations in this light mass region.