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arXiv · hep-ph/9904398

Nonresonant Semileptonic Heavy Quark Decay

Nathan Isgur
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Abstract

In both the large N_c limit and the valence quark model, semileptonic decays are dominated by resonant final states. Using Bjorken's sum rule in an "unquenched" version of the quark model, I demonstrate that in the heavy quark limit nonresonant final states should also be produced at a significant rate. By calculating the individual strengths of a large number of exclusive two-body nonresonant channels, I show that the total rate for such processes is highly fragmented. I also describe some very substantial duality-violating suppression factors which reduce the inclusive nonresonant rate to a few percent of the total semileptonic rate for the finite quark masses of B decay, and comment on the importance of nonresonant decays as testing grounds for very basic ideas on the structure, strength, and significance of the quark-antiquark sea and on quark-hadron duality in QCD.

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Nathan Isgur. 1999-04-19. Nonresonant Semileptonic Heavy Quark Decay. https://doi.org/10.1103/physrevd.60.074030

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