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Register a new userComment on Gamma-ray linear polarization measurements in textsuperscript{129}Ba
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S. Chakraborty
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The $ E2/M1 $ multipole mixing ratio ($ delta $), reported by J. Gizon et al. Phys. Rev. C 17, 596 (1978), for 365 keV $ gamma $-transition in isotope[129]Ba is reevaluated and found altered. Experimentally determined angular distribution coefficients indicate a large E2 admixture in the 365 keV $ gamma $-ray. Indeed, it is found in better agreement with the reported linear polarization value for this $ gamma $-ray.
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Masses adjacent to the classical waiting-point nuclide 130Cd have been measured by using the Penning- trap spectrometer ISOLTRAP at ISOLDE/CERN. We find a significant deviation of over 400 keV from earlier values evaluated by using nuclear beta-decay data. The new measurements show the reduction of the N = 82 shell gap below the doubly magic 132Sn. The nucleosynthesis associated with the ejected wind from type-II supernovae as well as from compact object binary mergers is studied, by using state-of-the-art hydrodynamic simulations. We find a consistent and direct impact of the newly measured masses on the calculated abundances in the A = 128 - 132 region and a reduction of the uncertainties from the precision mass input data.
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