Excited state contributions to the heavy baryon fragmentation functions in a quark-diquark model

Spin dependent fragmentation functions for heavy flavor quarks to fragment into heavy baryons are calculated in a quark-diquark model. The production of intermediate spin 1/2 and 3/2 excited states is explicitly included. The resulting ${\Lambda }_b$ production rate and polarization at CERN LEP energies are in agreement with experiment. The ${\Lambda }_c$ and ${\Xi }_c$ functions are also obtained. The spin independent $f_1\mathrm{}\left(z\right)\mathrm{}$ is compared to data. The integrated values for production rates agree with the data.