Speaker
Description
In the last years, several exotic states were observed in the charm sector; such particles cannot be interpreted as regular baryons or mesons and are thought to be either quark bags or molecular states. To unveil their nature, it is crucial to experimentally constrain the strong force that governs the interaction between the charm hadrons and other hadrons, for instance, via the measurement of the scattering parameters. The knowledge of the strong interaction in the charm sector is essential also for the study of ultrarelativistic heavy–ion collisions. In fact, during the hadronic phase of the system expansion, the charm hadrons can interact with the other particles produced in the collision, mainly light-flavor hadrons, via elastic and inelastic processes. These interactions modify the heavy-ion observables, and, to disentangle this effect from the signatures of the quark-gluon plasma formation, the scattering parameters of the charm hadrons with light-flavor hadrons are required. Despite the importance of constraining the charm-hadron interactions, the available experimental knowledge is very poor: so far, only the D-proton system was investigated, by using the femtoscopy technique in small systems at the LHC. In this contribution, these studies are extended, focusing on the open-charm and light-flavor meson systems. The measurement of the final-state strong interaction is performed using high-multiplicity pp collisions at sqrt(s) = 13 TeV collected by the ALICE Collaboration, and, employing the femtoscopy method, the scattering parameters of D± and D*± mesons with charged pions and kaons are extracted for the first time.
