Analytic Study of Disoriented Chiral

By introducing a quark source in the nonlinear σ model, we obtain an analytic boost-invariant solution as a candidate for the disoriented chiral condensate (DCC) in 3+1 dimensions. In order to trigger formation of the DCC, a strong transfer of axial isospin charge must occur between the expanding source and the interior in the baked Alaska scenario. An explicit chiral symmetry breaking is incorporated in the isospin-uniform solution by connecting the decay period to the formation period. Quantitative estimates are presented with our simple solution. At least in this class of solutions, the explicit symmetry breaking masks almost completely the disorientation which would be reached asymptotically in the symmetric limit.