Precision Flavour Physics with $B\to K\nu\bar\nu$ and $B\to Kl^+l^-$

TL;DR

This paper demonstrates that combined analysis of specific B meson decays enables precise new physics tests with minimal theoretical uncertainties, highlighting the importance of future measurements at advanced facilities.

Contribution

It introduces a method to test new physics using B decay modes with negligible form factor uncertainties, emphasizing the potential of Super Flavour Factories.

Findings

Residual theory errors are at the level of several percent.

Combined analysis enhances sensitivity to new physics.

Supports future measurements at Super Flavour Factories.

Abstract

We show that a combined analysis of $B\to K\nu\bar\nu$ and $B\to Kl^+l^-$ allows for new physics tests practically free of form factor uncertainties. Residual theory errors are at the level of several percent. Our study underlines the excellent motivation for measuring these modes at a Super Flavour Factory.