English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

An accurate low-energy dispersive parametrization of the scalar Kpi formfactor was constructed some time ago in terms of a single parameter guided bythe Callan-Treiman low-energy theorem. A similar twice subtracted dispersiveparametrization for the vector Kpi form factor will be investigated here. Therobustness of the parametrization of these two form factors will be studied ingreat detail. In particular the cut-off dependence, the isospin breakingeffects and the possible, though not highly probable, presence of zeros in theform factors will be discussed. Interesting constraints in the latter case willbe obtained from the soft-kaon analog of the Callan-Treiman theorem and acomparison with the recent tau --> K pi nu_tau data.

Dispersive representation and shape of the Kl3 form factors: robustness