High-precision mass measurement of neutron-rich 96Kr

While the nuclear deformation in the region around Z = 40 and N = 60 has been studied in great detail, the possible onset of nuclear deformation in the isotopic chain of krypton (Z = 36) is still a subject of controversy. Here, we present a high-precision mass measurement of the neutron-rich nuclide ⁹⁶Kr, as measured by the Multiple-Reflection Time-of-Flight Mass Spectrometer (MR-TOF-MS) at TRIUMF’s Ion Trap for Atomic and Nuclear Science (TITAN). A statistical method, based on a hyper-exponentially modified Gaussian, has been employed to model the data. As such, the uncertainty introduced by overlapping peaks from beam contaminants was reduced and the mass excess of ⁹⁶Kr determined to be -53097(57)keV. The capability of the method has been confirmed with measurements of the stable isotopic pair ⁴⁰Ar/⁴⁰Ca, in which a relative accuracy Δm/m of 3.5 ⋅ 10^{− 8} and a mass resolving power of more than 400000 were achieved.

Duke Scholars

Author Jens Dilling Physics