Coherent state formulation of pion radiation from nucleon antinucleon   annihilation
  We assume that nucleon antinucleon annihilation is a fast process leading to a classical coherent pion pulse. We develop the quantum description of such pion waves based on the method of coherent states. We study the consequences of such a description for averages of charge types and moments of distributions of pion momenta with iso-spin and four-momentum conservation taken into account. We briefly discuss the applicability of our method to annihilation at rest, where we find agreement with experiment, and suggest other avenues for its use. 
R.D.Amado, F.Cannata, J.-P.Dedonder, M.P.Locher and Bin Shao