Improving the Hadron Physics of Non-Standard-Model Decays: Example   Bounds on R-parity Violation
  Using the example of selected decays driven by R-parity-violating supersymmetric operators, we demonstrate how strong final-state interactions can be controlled quantitatively with high precision, thus allowing for a more accurate extraction of effective parameters from data. In our examples we focus on the lepton-flavor-violating decays tau --> mu pi+ pi-. In R-parity violation these can arise due to the product of two couplings. We find bounds that are an order of magnitude stronger than previous ones. 
J. T. Daub, H. K. Dreiner, C. Hanhart, B. Kubis, U.-G. Mei{\ss}ner
hep-ph hep-ex