Hadronization by color bremsstrahlung

Particle production in the central plateau of hadronic final states is calculated in a perturbative QCD model. We assume that the controlling process is bremsstrahlung of gluons. We find important differences between the spectrum produced in soft hadronic collisions and the spectrum in $e^{+}{e}^{-}$ annihilation. Describing soft hadronic collisions with the Low-Nussinov model, we find that the central plateau is independent of total energy, but depends strongly on the momentum transfer in the soft-gluon exchange. In contrast, the quark jets from $e^{+}{e}^{-}$ annihilation have a central plateau growing with energy. The strong momentum dependence in the hadron-induced plateau arises from the cancellations in the amplitude associated with the gauge invariance of the theory.