Elsevier

Nuclear Physics A

Volume 540, Issues 3–4, 27 April 1992, Pages 501-519
Nuclear Physics A

Determination of |Vud| from Fermi decays and the unitarity of the KM-mixing matrix

https://doi.org/10.1016/0375-9474(92)90171-FGet rights and content

Abstract

We re-evaluate the ƒt-values and their radiative corrections for the eight superallowed β+ decays for which very accurate data are available and also include the results for 10C, for which the measurements are approaching a similar accuracy. The main new feature is a recalculation of the nuclear-structure dependent part CNS of the O(α) radiative correction using wave functions more realistic than those used previously. This determines the value of the element Vud of the quark mixing matrix. Moreover, we recalculate Vus in the framework of a quark model. The resulting values of these two matrix elements indicate a violation of unitarity of the mixing matrix. We discuss implications of this regarding possible extensions of the minimal version of the standard model of electroweek interactions.

References (48)

  • J.C. Hardy et al.

    Nucl. Phys.

    (1990)
  • S.W. Kikstra et al.

    Nucl. Phys.

    (1991)
  • S. Raman et al.

    At. Data Nucl. Data Tables

    (1975)
  • C.W. de Jager et al.

    At. Data Nucl. Data Tables

    (1974)
  • H. Behrens et al.

    Nucl. Phys.

    (1972)
  • J.M. Feagin et al.

    Phys. Lett.

    (1979)
    J.M. Feagin et al.

    Phys. Lett.

    (1979)
  • V.T. Koslowsky et al.
  • B.A. Brown et al.

    Phys. Rev. Lett.

    (1980)
  • B.H. Wildenthal

    Prog. Part. Nucl. Phys.

    (1984)
    B.A. Brown et al.

    Ann. Rev. Nucl. Part. Sci.

    (1988)
  • T.T.S. Kuo et al.

    Nucl. Phys.

    (1968)
  • M. Sakakura et al.

    Phys. Lett.

    (1976)
  • D.H. Wilkinson

    Phys. Lett.

    (1990)
  • G. Rasche et al.

    Mod. Phys. Lett.

    (1990)
  • A. Denner et al.

    Nucl. Phys.

    (1990)
  • H. Leutwyler et al.

    Z. Phys.

    (1984)
  • W. Jaus

    Phys. Rev.

    (1991)
  • J. Gasser et al.

    Nucl. Phys.

    (1985)
  • H.H. Williams et al.

    Phys. Rev. Lett.

    (1974)
  • W.S. Woolcock

    Mod. Phys. Lett.

    (1991)
  • Y. Nagai et al.

    Phys. Rev.

    (1991)
  • W. Jaus et al.

    Phys. Rev.

    (1990)
  • G. Rasche et al.

    Phys. Rev.

    (1991)
  • H. Behrens et al.

    Electron radial wave functions and nuclear beta-decay

    (1982)
  • W.J. Marciano et al.

    Phys. Rev. Lett.

    (1986)
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