Baryon Production ine+e−Annihilation ats=29GeV: Clusters or Diquarks?

We use the time-projection chamber detector to study mechanisms of baryon production in the central rapidity region of jets from $e^{+}{e}^{-}$ annihilation. On the basis of angular correlations between protons and antiprotons, we exclude the isotropic decay of heavy mesonic clusters as a dominant source of baryons at 95% confidence level. The diquark mechanisms used in string fragmentation models reproduce the data, provided that diquarks are formed in a two-step process which allows mesons to be produced in between the baryon and antibaryon.