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

@article{Colangelo2001TheQC,
title={The quark condensate from K(e(4)) decays.},
author={G Colangelo and J. Gasser and Heinrich Leutwyler},
journal={Physical review letters},
year={2001},
volume={86 22},
pages={
5008-10
}
}
• Published 6 March 2001
• Physics, Medicine
• Physical review letters
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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