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Extended van Royen-Weisskopf formalism for lepton-antilepton meson decay widths within non-relativistic quark models

L. A. Blanco·R. Bonnaz·B. Silvestre-Brac·F. Fernandez·A. Valcarce
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Abstract

The classical van Royen-Weisskopf formula for the decay width of a meson into a lepton-antilepton pair is modified in order to include non-zero quark momentum contributions within the meson as well as relativistic effects. Besides, a phenomenological electromagnetic density for quarks is introduced. The meson wave functions are obtained from two different models: a chiral constituent quark model and a quark potential model including instanton effects. The modified van Royen-Weisskopf formula is found to improve systematically the results for the widths, giving an overall good description of all known decays.

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L. A. Blanco, R. Bonnaz, B. Silvestre-Brac, F. Fernandez, A. Valcarce. 2001-09-27. Extended van Royen-Weisskopf formalism for lepton-antilepton meson decay widths within non-relativistic quark models. https://doi.org/10.1016/s0375-9474(01)01290-8

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