Measuring the phase between strong and EM J/Psi decay amplitudes
  A c.m. energy scan below the J/Psi peak foreseen in the next future at BESIII can probe the existence in all the exclusive possible final states of an interference pattern between the resonant e+e- => J/Psi => hadrons and non-resonant e+e+ => hadrons amplitudes. The relative phase of the strong J/Psi decay amplitude with respect to the electromagnetic one can hence be accessed for the first time in a model independent way. 
M. Maggiora (for the BESIII Collaboration)
hep-ex