Critical-point boundary for the nuclear quantum phase transition near A=100 from mass measurements of (96,97)Kr
Physical Review Letters
|September 28, 2010
Abstract:
Mass measurements of (96,97)Kr using the ISOLTRAP Penning-trap spectrometer at CERN-ISOLDE are reported, extending the mass surface beyond N=60 for Z=36. These new results show behavior in sharp contrast to the heavier neighbors where a sudden and intense deformation is present. We interpret this as the establishment of a nuclear quantum phase transition critical-point boundary. The new masses confirm findings from nuclear mean-square charge-radius measurements up to N=60 but are at variance with conclusions from recent gamma-ray spectroscopy.
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