We study a string fragmentation model in which the probability distribution for the locations of the vertices is parametrized explicitly in terms of their space-time coordinates measured from the point of the onset of separation of the quark and the antiquark. An iterative procedure is presented to fragment a finite-mass string into hadrons. We apply the model to calculate the rapidity distribution of the produced hadrons, which is found to give a good fit to the experimental data for $e^{+}-e^{-}$ annihilation at 29 GeV. From the parameters characterizing the probability distribution of the vertices, we determine the average hadron formation time in the fragmentation of the string.

• Received 21 May 1990

DOI:https://doi.org/10.1103/PhysRevD.44.679