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arXiv · hep-ph/9311287

1/m_c Expansion of Omega_b -> Omega_c^(*) Semileptonic Decay Form Factors

Abstract

A simple model of Omega_Q and Omega_Q^(*) baryons containing one heavy quark Q is constructed. Amplitudes are represented by loop graphs with one line for the heavy quark and another for the light degrees of freedom. The latter are modelled as a freely-propagating vector particle interacting nonlocally with the heavy baryon and a free heavy quark. It is argued that the physics of confinement plays an inessential role in determining semileptonic decay form factors. The model has a well-defined heavy-quark expansion which has a form consistent (through order 1/m_Q) with that determined by QCD through the heavy-quark effective theory. The slope of the Isgur-Wise function is consistent with the Bjorken sum rule bound. The effect of the Omega_Q^* - Omega_Q mass splitting on the first-order form factors is examined.

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BibTeXRIS

M. Sutherland. 1993-11-12. 1/m_c Expansion of Omega_b -> Omega_c^(*) Semileptonic Decay Form Factors. https://doi.org/10.1007/bf01577549

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