The quark condensate from K_{e_4} decays
arXiv:hep-ph/0103063 · doi:10.1103/PhysRevLett.86.5008
Abstract
We show that, independently of the size of the quark condensate, chiral symmetry correlates the two S-wave ÏÏscattering 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.
4 pages (LaTex), 3 figures