Extending the low-$Z$ "border'' of the $A=100$ region of deformation with precision mass spectrometry of $^{96-98}$Kr
D. Lunney, V. Manea, M. Mougeot, L. Nies, N. A. Althubiti, D. Atanasov, K. Blaum, A. Herlert, W. -J. Huang, J. Karthein, I. Kulikov, Yu. A. Litvinov, D. Neidherr, T. R. Rodríguez, M. Rosenbusch, L. Schweikhard, T. Steinsberger, A. Welker, F. Wienholtz, R. N. Wolf
公開日: 2025/9/5
Abstract
The onset of collective nuclear behavior in the ${N=60}$, ${A\sim100}$, region is examined through high-precision mass measurements of $^{96-98}$Kr, performed with the ISOLTRAP mass spectrometer at ISOLDE, CERN. Our results for $^{96-97}$Kr agree with previous measurements, with our new $^{97}$Kr Penning-trap mass value three times more precise. The mass value of $^{98}$Kr is measured for the first time. The new mass surface, together with comparisons to beyond-mean-field theoretical predictions, suggests that collectivity persists for the ${Z=36}$ isotopes, blurring the apparent ``low-$Z$ boundary'' of this deformed region.