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arXiv · 0711.3450

Matching Chiral Perturbation Theory and the Dispersive Representation of the Scalar Kpi Form Factor

Veronique Bernard·Emilie Passemar
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Abstract

We perform a matching of the two loop-chiral perturbation theory representation of the scalar Kpi form factor to a dispersive one. Knowing the value of F_K/F_pi and f_+(0) in the Standard Model (SM) allows to determine two O(p^6) 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 F_K/F_pi, f_+(0), a certain combination of non-standard couplings, the deviation of the Callan-Treiman theorem and the two O(p^6) LECs.

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Veronique Bernard, Emilie Passemar. 2008-03-13. Matching Chiral Perturbation Theory and the Dispersive Representation of the Scalar Kpi Form Factor. https://doi.org/10.1016/j.physletb.2008.02.004

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