Isotope-shift measurements and King-fit analysis in nickel isotopes

Nuclear Charge Radii of the Nickel Isotopes $^{58-68,70}$Ni

“…The changes in mean-square nuclear charge radii δ r 2 c 60,A ≡ r 2 c A − r 2 c 60 are obtained using the field-shift factor F = −783(94) MHz/fm 2 and the massshift factor M α=396 = 950(5) GHz u, as explained in [18]. These values are in excellent agreement with independent measurements reported in [35]. Negligible deviations from our values in [18] arise from a correction in the analysis code but lead only to insignificant changes of δ r Theory.…”

Charge Radii of Ni55,56 Reveal a Surprisingly Similar Behavior at N=28Sommer1, König2, Rossi3 et al. 2022Phys. Rev. Lett.Self Cite15380View full textAdd to dashboardCite

“…For the low-production isotopes 54 Ni and 55 Ni, the uncertainties of the isotope shifts are dominated by the fit uncertainty of their centroid positions. For 56 Ni and the stable 58 Ni, uncertainties of the frequency measurements [50] and an observed deviation between bunched-beam and continuous-beam measurements [51] are the prevailing contributions to the isotope-shift uncertainties.…”

“…where K α and F are the so called mass-and fieldshift factors, respectively, and plot procedure by comparing the isotope shifts of stable nickel isotopes, measured off-line at BECOLA, with their known differential charge radii from literature [53]. This King fit analysis is detailed in [51]. The total root-meansquare (rms) charge radii R c were then determined with respect to the reference value R c ð 60 NiÞ [53].…”

Charge Radius of Neutron-deficient $^{54}$Ni and Symmetry Energy Constraints Using the Difference in Mirror Pair Charge Radii

“…The uncertainty is dominated by the statistical uncertainty of the 54 Ni resonance centroid (7.5 MHz). A discussion of the systematic uncertainty contributions is detailed in [41]. From the obtained isotope shifts, the differential mean square (ms) charge radius was extracted as δ r 2 A,A = (δν A,A − µ A,A K α )/F + µ A,A α [42] with the offset parameter α, the field-shift factor F , the offsetdependent mass-shift factor K α , and…”

“…, where m A and m A are the nuclear masses, and m e is the electron mass. The F and K α were separately determined [41] by the King-fit analysis [43] using re-measured isotope-shifts of the stable isotopes, and are listed in Tab. I for 58 Ni and 60 Ni as reference isotopes.…”