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arXiv · hep-ph/0009103

Semileptonic form factors - a model-independent approach

T. Coleman·M. G. Olsson·S. Veseli
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Abstract

We demonstrate that the B->D(*) l nu form factors can be accurately predicted given the slope parameter rho^2 of the Isgur-Wise function. Only weak assumptions, consistent with lattice results, on the wavefunction for the light degrees of freedom are required to establish this result. We observe that the QCD and 1/m_Q corrections can be systematically represented by an effective Isgur-Wise function of shifted slope. This greatly simplifies the analysis of semileptonic B decay. We also investigate what the available semileptonic data can tell us about lattice QCD and Heavy Quark Effective Theory. A rigorous identity relating the form factor slope difference rho_D^2-rho_A1^2 to a combination of form factor intercepts is found. The identity provides a means of checking theoretically evaluated intercepts with experiment.

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T. Coleman, M. G. Olsson, S. Veseli. 2000-09-14. Semileptonic form factors - a model-independent approach. https://doi.org/10.1103/physrevd.63.032006

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