Dalitz Plots and Hadron Spectroscopy
  In this master thesis I discuss how the weak three-body decay B^+ --> pi^- pi^+ K^+ is related to the strong interactions between the final-state particles. Current issues in hadron spectroscopy define a region of interest in a Dalitz plot of this decay. This region is roughly characterized by energies from 0 to 1.6 GeV of the pi^- pi^+ and the pi^- K^+ system, and energies from 3 to 5 GeV of the pi^+ K^+ system. Therefore I propose to use for the former two systems elastic unitarity (Watson's theorem) as an approximate ansatz, and a non-vanishing forward-peaked amplitude for the latter system. I introduce most basic concepts in detail with the intention that this be of use to non-experts interested in this topic. 
Adrian Wuethrich