Constraining the low-energy S=-2 meson-baryon interaction with two-particle correlations

Abstract

The two-particle correlation technique applied to $K^-\Lambda$ pairs in pp collisions at LHC recently provided the most precise data on the strangeness $S=-2$ meson-baryon interaction. In this letter, we use for the first time femtoscopic data to constrain the parameters of a low-energy effective QCD Lagrangian. The tuned model delivers new insights on the molecular nature of the $\Xi(1620)$ and $\Xi(1690)$ states. This procedure opens the possibility to determine higher order corrections, directly constraining QCD effective models particularly in the multi-strange and charm sectors.