Reptation of star polymers in a network: Monte Carlo results of   diffusion coefficients
  We report on Monte Carlo results of diffusion coefficients of lattice star polymers trapped inside a fixed network (de Gennes model). It is found that our data are in agreement with the Helfand-Pearson exponential factor \alpha=0.29. For the pre-exponential power law exponent we find \beta=2. In contrast to existing theoretical predictions, we find that the number of arms f leads to a pre-exponential factor of the form exp(-0.75 f). 
G.T. Barkema (ITP, Utrecht Univ.) and A. Baumgaertner   (Forschungszentrum Juelich)