Meson and baryon femtoscopy in heavy-ion collisions at ALICE

TL;DR

This paper analyzes femtoscopic correlations of various particles in heavy-ion and proton-proton collisions at the LHC, revealing source size scaling and the impact of final state interactions on baryon yields.

Contribution

It provides the first femtoscopic measurements of multiple particle pairs in Pb-Pb and pp collisions at LHC energies, highlighting collective behavior and final state effects.

Findings

Emission source sizes scale with transverse mass, consistent with hydrodynamics.

Baryon-antibaryon correlations suggest significant annihilation effects.

Results help explain proton multiplicity discrepancies at LHC.

Abstract

We present results of femtoscopic analysis with K0s-K0s, Kch-Kch, p-p, pbar-pbar, p-pbar and lambda-antilambda in Pb-Pb collisions at sqrt{s_NN}=2.76 TeV and K0s-K0s in pp collisions at sqrt{s}=7 TeV registered by ALICE at the LHC. The femtoscopic radius is extracted from the one-dimensional correlation functions. The analysis reveals that the emission source sizes of pions, kaons and protons measured in heavy-ion collisions exhibit approximate transverse mass scaling which is consistent with hydrodynamic collectivity prediction. Furthermore, baryon-antibaryon correlations are investigated to study the influence of Final State Interactions (annihilation). It may contribute to lower multiplicities of protons observed at LHC energies, with respect to predictions from thermal models.