Pion–kaon femtoscopy and the lifetime of the hadronic phase in Pb−Pb collisions at √ sNN = 2.76 TeV

Abstract

Femtoscopic correlations between charged pions and kaons for different charge combinations are measured in Pb-Pb collisions at root s(NN) = 2.76 TeV with ALICE at the LHC. The three-dimensional pion-kaon (pi - K) correlation functions and double ratios in the out-side-long pair rest frame are studied in different centrality bins. The pi - K femtoscopic source size parameter (R-out) and emission asymmetry (mu(out)) are extracted. It is observed that the average source size of the system and the emission asymmetry between pions and kaons increase from peripheral to central events.