Laser spectroscopy techniques have been extensively used to determine fundamental propertiesof the atomic nuclei across broad swaths of the chart of the nuclides, including both stable and unstable(radioactive) nuclei. However, the transition metal region has proven dif- cult to study with laser spectroscopy due to the electronic structure of the transition metals and short half-lives of radioactive nuclei. Experimental access to the transition metal region for laser spectroscopy studies would contribute to the understanding of nuclear structure and provide important data for nuclear stockpile stewardship. In order to gain experimental access to the transition metal region, an optical pumping technique can be performed to manipulate the electronic populations of ions. Ions in low-energy electronic states are excited to a state that preferentially decays to one accessible for precision laser spectroscopy measurements. This work presents the results of commissioning experiments of an optical pumping system at the BEam COoling and LAser(BECOLA) spectroscopy facility, located at the National Superconducting Cylotron Laboratory. An optical pumping simulation was developed to predict the gain in sensitivity for the rst- and second-row transition metals from optical pumping and guide the commissioning experiments. The results of the simulation show that most transition metal elements can benet from the optical pumping technique. New instrumentation, including a pulsed laser system and a free-space light transport system, were installed at BECOLA to perform the optical pumping technique on ions in a Radio-Frequency Quadrupole(RFQ) cooler/buncher ion trap. The commissioning experiments were performed with a beam of stable Zr+, produced by an oine plasma discharge sputter ion source and delivered to the BECOLA RFQ ion trap. Two optical pumping schemes were investigated, exciting ions from the 4d25s 4F3/2 and 4d25s4F5/2 states. The manipulation of the electronic populations was probed through changes in the uorescence signal in subsequent collinear laser spectroscopy measurements through the excitation of ions in the 4d25s 4F3/2 state. The electronic populations of ions in the RFQ ion trap were successfully manipulated while the ions are quickly rethermalized to a room temperature distribution by collisions with a He buffer gas. The experimental results were in good agreement with the optical pumping simulation and based on that validation, BECOLA is well situated to study rare isotopes of essentially all transition metal elements at the Facility for Rare Isotope Beams(FRIB).
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