Bernhard Maaß, Wouter Ryssens, Kristian König, M. Bender, D. P. Burdette, Jason Clark, Adam Dockery, Guilherme Grams, Max Horst, Phillip Imgram, K. Minamisono, Patrick Müller, Peter Mueller, W. Nörtershäuser, Skyy Pineda, Simon Rausch, Laura Renth, Brooke J. Rickey, D. Santiago-Gonzalez, G. Savard, F. Sommer, A. A. Valverde
We show that triaxial deformation impacts charge radii in models that feature shell effects, in contrast to what could be concluded from a liquid drop analysis.
We present the first measurements with a new collinear laser spectroscopy setup at the Argonne Tandem Linac Accelerator System, utilizing its unique capability to deliver neutron-rich refractory metal isotopes produced by the spontaneous fission of ^{252}Cf. We measured isotope shifts from optical spectra for nine radioactive ruthenium isotopes ^{106-114}Ru, reaching deep into the mid-shell region. The extracted charge radii are in excellent agreement with predictions from the Brussels-Skyrme-on-a-Grid models that account for the triaxial deformation of nuclear ground states. We show that triaxial deformation impacts charge radii in models that feature shell effects, in contrast to what could be concluded from a liquid drop analysis. This indicates that this exotic type of deformation should not be neglected in regions where it is known to occur, even if its presence cannot be unambiguously inferred through laser spectroscopy.