Four-pion production

Abstract

Starting from the low-energy structure derived from QCD, we extend the amplitudes for four-pion production in e+ e- annihilation and tau decays up to invariant four-pion masses of 1 GeV. Cross sections and branching ratios BR(rho^0 -> 4 pi) are compared with available data.

Comments: 4 pages, 3 figures, contribution to Proc. of QCD'02, Montpellier, July 2002, misprints corrected