Analyticity constraints on the strangeness changing vector current and applications to $\tau \to K\pi {\nu }_{\tau }$, $\tau \to K\pi \pi {\nu }_{\tau }$

B. Moussallam

We discuss matrix elements of the strangeness changing vector current using their relation, due to analyticity, with $\pi K$ scattering in the $P$-wave. We take into account experimen…