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arXiv · hep-ph/9602376

B to J/Psi+X in the Inclusive Parton and the ACCMM Model

W. F. Palmer·E. A. Paschos·P. H. Soldan
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Abstract

The parton model as developed for semileptonic B decays is applied to the inclusive decay B to J/Psi+X. We calculate the momentum spectrum of the J/Psi using a one-parameter distribution function for the heavy quark, taken from production experiments, and compare our results with recent data from CLEO which fixes the distribution parameter epsilon_p. An analogous calculation is carried out in the ACCMM model where the data determines the Fermi motion parameter p_f. The models give a good description of the data, provided in each of them the parameter in the distribution function is chosen to correspond to a softer b quark momentum distribution than that commonly used in studies of semileptonic B decays. In particular we arrive at epsilon_p = O(0.008) and p_f = O(0.55 GeV), respectively. The latter value (p_f = 0.5 GeV) produces in the ACCMM model 10^2*|V_ub/V_cb|^2=1.03, which removes a former supposed discrepancy with the ISGW model. Finally, the strength of the effective color singlet coefficient is found to be a_2 = O(0.28) in both models.

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W. F. Palmer, E. A. Paschos, P. H. Soldan. 1996-02-23. B to J/Psi+X in the Inclusive Parton and the ACCMM Model. https://arxiv.org/abs/hep-ph/9602376

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