Precise measurements of ruthenium nuclei can shed light on early universe

Scientists at Argonne National Laboratory have achieved highly precise measurements of unstable ruthenium nuclei, marking a significant milestone in nuclear physics. Using the ATLANTIS apparatus and a new collinear laser spectroscopy setup at the Argonne Tandem Linac Accelerator System, the team measured isotope shifts for nine radioactive ruthenium isotopes (106–114Ru). These measurements closely matched predictions from advanced nuclear models, specifically the Brussels-Skyrme-on-a-Grid models, which account for triaxial deformation—a complex, almond-shaped distortion of nuclear ground states. This validation is crucial because theoretical models have historically struggled to accurately predict properties of unstable nuclei with complex shapes. The study’s findings not only confirm the reliability of these sophisticated nuclear models but also enhance confidence in their use for understanding astrophysical processes such as star formation, evolution, and explosions where elements are synthesized. Ruthenium, with its range of unstable isotopes exhibiting intricate nuclear structures, serves as an ideal element for testing these models. The