The quark condensate from K(e(4)) decays.

  title={The quark condensate from K(e(4)) decays.},
  author={G Colangelo and J. Gasser and Heinrich Leutwyler},
  journal={Physical review letters},
  volume={86 22},
We show that, independently of the size of the quark condensate, chiral symmetry correlates the two S-wave pipi scattering lengths. In view of this constraint, the new precision data on K(e(4)) decay allow a remarkably accurate determination of these quantities. The result confirms the hypothesis that the quark condensate is the leading order parameter. 

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