Momentum distribution in the decay B->J/psi+X

We combine the NRQCD formalism for the inclusive color singlet and octet production of charmonium states with the parton and the ACCMM model, respectively, and calculate the momentum distribution in the decay B-->J/psi+X. Neglecting the kinematics of soft gluon radiation. we find that the motion of the b quark in the bound state can account. to a large extent, for the observed spectrum, The parton model gives a satisfactory presentation of the data, provided that the heavy quark momentum distribution is taken to be soft. To be explicit. we obtain epsilon(p) similar to 0.008-0.012 for the parameter of the distribution function of Peterson et al. The ACCMM model can account for the data more accurately. The preferred Fermi momentum p(F) congruent to 0.57 GeV is in good agreement with recent studies of the heavy quark's kinetic energy.