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Kobayashi-Maskawa Angles and Su(3) Breaking in Hyperon Beta-Decay
Physical Review D (1987)
  • JF Donoghue
  • BR Holstein
  • SW Klimt
The determination of the Kobayashi-Maskawa matrix element Vus from hyperon β decays has long had a hidden uncertainty due to the almost universal assumption of SU(3) invariance in Cabibbo-type fits, especially since the data definitely indicate the presence of SU(3) breaking. We have reanalyzed the hyperon-decay data using the pattern of symmetry breaking predicted by the quark model including the center-of-mass correction. We find that the SU(3)-broken picture is far superior to the assumption of perfect SU(3), and provides a good fit to experiment. The sensitivity of Vus to the breaking is not large and we find Vus=0.220+/-0.001+/-0.003 (the errors are experimental and theoretical, respectively), in agreement with the results from kaon decay by Leutwyler and Roos.
Publication Date
February 1, 1987
Citation Information
JF Donoghue, BR Holstein and SW Klimt. "Kobayashi-Maskawa Angles and Su(3) Breaking in Hyperon Beta-Decay" Physical Review D Vol. 35 Iss. 3 (1987)
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