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تسجيل مستخدم جديدHigh-precision mass measurement of $^{168}$Yb for verification of nonlinear isotope shift
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The absolute mass value of $^{168}$Yb has been directly determined with the JYFLTRAP Penning trap mass spectrometer at the Ion Guide Isotope Separator On-Line (IGISOL) facility. A more precise value of the mass of $^{168}$Yb is needed to extract possible signatures of beyond standard model physics from high-precision isotope shift measurements of Yb atomic transition frequencies. The measured mass-excess value, ME($^{168}$Yb) = $-$61579.846(94) keV, is 12 times more precise and deviates from the Atomic Mass Evaluation 2016 value by 1.7$sigma$. The impact on precision isotope shift studies of the stable Yb isotopes is discussed.
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The double-electron capture and the electron capture with positron emission in $^{168}$Yb have been investigated for the first time at the STELLA facility of the Gran Sasso underground laboratory (Italy) measuring 371 g of highly purified ytterbium o
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The ground-state-to-ground-state $beta$-decay $Q$-value of $^{135}textrm{Cs}(7/2^+)to,^{135}textrm{Ba}(3/2^+)$ was directly measured for the first time utilizing the Phase-Imaging Ion-Cyclotron Resonance (PI-ICR) technique at the JYFLTRAP Penning-tra
p setup. It is the first direct determination of this $Q$-value and its value of 268.66(30),keV is a factor of three more precise than the currently adopted $Q$-value in the Atomic Mass Evaluation 2016. Moreover, the $Q$-value deduced from the $beta$-decay endpoint energy has been found to deviate from our result by approximately 6 standard deviations. The measurement confirms that the first-forbidden unique $beta^-$-decay transition $^{135}textrm{Cs}(7/2^+)to,^{135}textrm{Ba}(11/2^-)$ is a candidate for antineutrino-mass measurements with an ultra-low $Q$-value of $0.44(31)$ keV. This $Q$-value is almost an order of magnitude smaller than in any presently running or planned direct (anti)neutrino-mass experiment.
We report the mass measurement of $^{56}$Cu, using the LEBIT 9.4T Penning trap mass spectrometer at the National Superconducting Cyclotron Laboratory at Michigan State University. The mass of $^{56}$Cu is critical for constraining the reaction rates
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