Novel model for particle emission in small collision systems

Abstract

AbstractCollider experiments provide an opportunity to produce particles at close distances and momenta. The measured correlation functions between particles can provide information on both the effective emission source and the interaction potential. In recent years, experiments at the LHC have shown that precision studies of the strong interaction are possible using correlation techniques, provided a good handle on the source function. The current work presents a new numerical framework called Common Emission in CATS (CECA), capable of simulating the effective emission source of an N-body system based on the properties of the single particles. The framework differentiates between primordial particle emission and particle production through resonances, allowing to verify the hypothesis proposed by the ALICE Collaboration that a common baryon–baryon emission source is present in small collision systems. The new framework is used to analyze ALICE data on $$\text{ pp }$$ pp and $$\text{ p }\Lambda $$ p Λ correlations and compare the results to previous studies based on the common emission source scenario. It is demonstrated that the best fit to the $$\text{ p }\Lambda $$ p Λ correlation data is obtained using a scattering length of $$1.15\pm 0.07$$ 1.15 ± 0.07  fm in the S = 1 channel. The new CECA framework provides an essential tool for precision studies in two-body systems and a consistent description of the source function in many-body systems.