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Covariant quark model of form factors in the heavy mass limit

A. Le Yaouanc·L. Oliver·O. Pène·J. -C. Raynal
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Abstract

We show that quark models of current matrix-elements based on the Bakamjian-Thomas construction of relativistic states with a fixed number of particles, plus the additivity assumption, are covariant in the heavy-quark limit and satisfy the full set of heavy-quark symmetry relations discovered by Isgur and Wise. We find the lower bound of $ρ^2$ in such models to be $3/4$ for ground state mesons, independently of any parameter. Another welcome property of these models is that in the infinite momentum limit the wave functions vanish outside the domain $0\le x \le 1$.

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A. Le Yaouanc, L. Oliver, O. Pène, J. -C. Raynal. 1995-07-19. Covariant quark model of form factors in the heavy mass limit. https://doi.org/10.1016/0370-2693(95)01285-0

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