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Precision Measurement of the 29Si, 33S, and 36Cl Binding Energies
Published
Author(s)
Maynard S. Dewey, Ernest G. Kessler Jr., R Deslattes, H G. Borner, M Jentschel, C Doll, P Mutti
Abstract
The binding energies of 29Si, 33S, and 36Cl have been measured with a relative uncertainty < 0.65 x 10-6 using a flat-crystal spectrometer. The unique features of these measurements are 1) nearly perfect crystals whose lattice spacing is known in meters, 2) a highly precise angle scale that is derived from first principles, and 3) a gamma-ray measurement facility that is coupled to a high flux reactor with near-core source capability. The binding energy is obtained by measuring all gamma-rays in a cascade scheme connecting the capture and ground states. The measurements require the extension of precision flat-crystal diffraction techniques to the 5-6 MeV energy region, a significant precision measurement challenge. The measured gamma-ray energies are in agreement with earlier precision measurements. The measured binding energies have an uncertainty that is significantly less (factors of 7, 67, and 16 for 29Si, 33S, and ^u36&Cl respectively) than the uncertainty that is associated with binding energies determined from atomic mass tables. The gamma-ray and atomic mass binding energies are consistent within 1.7 standard deviations.
Dewey, M.
, Kessler Jr., E.
, Deslattes, R.
, Borner, H.
, Jentschel, M.
, Doll, C.
and Mutti, P.
(2008),
Precision Measurement of the <sup>29</sup>Si, <sup>33</sup>S, and <sup>36</sup>Cl Binding Energies, Physics Review C
(Accessed October 9, 2025)