Dalitz plot analysis of the $D^+ \to K^-K^+K^+$ decay

Abstract

The resonant structure of the doubly Cabibbo-suppressed decay $D^+ \to K^-K^+K^+$ is studied for the first time. The measurement is based on a sample of pp-collision data, collected at a centre-of-mass energy of 8 TeV with the LHCb detector and corresponding to an integrated luminosity of 2 $fb^{−1}$. The amplitude analysis of this decay is performed with the isobar model and a phenomenological model based on an effective chiral Lagrangian. In both models the S-wave component in the $K^−K^+$ system is dominant, with a small contribution of the $\phi(1020)$ meson and a negligible contribution from tensor resonances. The $K^+K^−$ scattering amplitudes for the considered combinations of spin (0,1) and isospin (0,1) of the two-body system are obtained from the Dalitz plot fit with the phenomenological decay amplitude.