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arXiv · nucl-th/9704039

Semileptonic decays of heavy mesons

M. A. Ivanov·Yu. L. Kalinovsky·P. Maris·C. D. Roberts
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Abstract

The semileptonic and leptonic decays of heavy mesons are studied as a phenomenological application and exploration of a heavy-quark limit of Dyson-Schwinger equations. The single form factor, $ξ(w)$, which characterises the semileptonic decay in this limit, is calculated and compares well with recent experimental extractions. We obtain a lower bound of 1/3 on the slope-parameter $ρ^2 \equiv -ξ^\prime(1)$, which, in calculations with realistic input, is exceeded by a great deal: agreement with experimental data requiring $ρ^2 \sim 1.2 - 1.6$. The flavour and momentum dependence of the light-quark propagators has observable consequences.

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M. A. Ivanov, Yu. L. Kalinovsky, P. Maris, C. D. Roberts. 1997-04-17. Semileptonic decays of heavy mesons. https://doi.org/10.1016/s0370-2693(97)01323-3

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