ar X iv : 0 71 1 . 34 50 v 2 [ he p - ph ] 1 3 M ar 2 00 8 Matching Chiral Perturbation Theory and the Dispersive Representation of the Scalar Kπ Form Factor
نویسنده
چکیده
We perform a matching of the two loop-chiral perturbation theory representation of the scalar Kπ form factor to a dispersive one. Knowing the value of FK/Fπ and f+(0) in the Standard Model (SM) allows to determine two O(p) LECs, the slope of the scalar form factor and the deviation of the Callan-Treiman theorem. Going beyond the SM and assuming the knowledge of the slope of the scalar form factor from experiment, the matching allows us to determine the ratio of FK/Fπ, f+(0), a certain combination of non-standard couplings, the deviation of the Callan-Treiman theorem and the two O(p) LECs. 1Email: [email protected] 2Email: [email protected]
منابع مشابه
ar X iv : 0 71 1 . 34 50 v 1 [ he p - ph ] 2 1 N ov 2 00 7 Matching Chiral Perturbation Theory and the Dispersive Representation of the Scalar Kπ Form Factor
We perform a matching of the two loop-chiral perturbation theory representation of the scalar Kπ form factor to a dispersive one. Knowing the value of FK/Fπ and f+(0) in the Standard Model (SM) allows to determine two O(p) LECs, the slope of the scalar form factor and the deviation of the Callan-Treiman theorem. Going beyond the SM and assuming the knowledge of the slope of the scalar form fact...
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