A technique called “Femtoscopy” is used to measure two-particle correlations to study the strong interaction among hadrons. The excellent particle identification capabilities of the ALICE experiment as well as the small-inter particle distance of proton-proton collisions at the Large Hadron Collider (LHC) enables the first-time measurement of the p-φ correlation function with sufficient precision.
The so obtained genuine p-φ correlation function is compared to several model predictions. This allows to pin down a moderately attractive p-φ interaction with a small absorption cross-section in vacuum. A bound state is not supported by data. These results provide valuable input and constraints to theoretical models needed to correctly interpret the existing experimental data on the in-medium properties of the φ meson, related to the search for a partial restoration of chiral symmetry. Additionally, the coupling constant between φ mesons and nucleons is extracted, which can be related to the interaction among strangeness-containing particles predicted to emerge in the core region of neutron stars via fundamental symmetry relations.
Publication: Experimental Evidence for an Attractive p−ϕ Interaction
Prof. Dr. Laura Fabbietti
Professorin für Dichte und seltsame hadronische Materie
Technische Universität München