Strong and Weak Interactions in B to pi+ pi- K Decays
  To describe the weak three-body B decays into pi+ pi- K, we recently derived amplitudes based on two-body QCD factorization followed by pi+ pi- final state interactions in isoscalar S- and isovector P-waves. We study here the sensitivity of the results to the values of the B to f0(980) transition form factor and to the effective decay constant of the f0(980). 
B. Loiseau, B. El-Bennich, A. Furman, R. Kaminski, L. Lesniak