Meson Form-factors and Wave-functions with Wilson fermions

R. Gupta; D. Daniel; J. Grandy

doi:10.1016/0920-5632(93)90241-w

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arXiv · hep-lat/9211057

Meson Form-factors and Wave-functions with Wilson fermions

R. Gupta·D. Daniel·J. Grandy

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Abstract

Results for semi-leptonic form-factors for processes like $D \to K l ν$ and the Bethe-Salpeter amplitudes (BSA) for pion and rho mesons are presented. The form-factor data is consistent with previous calculations. We find that the long distance fall-off of BSA for both $π$ and $ρ$ is very well fit by an exponential, but surprisingly the effective mass governing this fall-off is lighter than the pion's. Lastly, by studying the dependence of $ρ$ polarization on separation direction we show that there is a measureable $l=2$ state in addition to $l=0$ in the BSA for the rho. (Talk presented by R. Gupta at LATTICE92. Latex needs macro package espcrc2.sty)

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R. Gupta, D. Daniel, J. Grandy. 1992-11-24. Meson Form-factors and Wave-functions with Wilson fermions. https://doi.org/10.1016/0920-5632(93)90241-w

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