K *(892)± resonance production in Pb-Pb collisions at √sNN=5.02 TeV

The production of K*(892)(+/-) meson resonance is measured at midrapidity (|y| < 0.5) in Pb-Pb collisions at root s(NN) = 5.02 TeV using the ALICE detector at the CERN Large Hadron Collider. The resonance is reconstructed via its hadronic decay channel K *( 892)(+/-) -> K-S(0)pi(+/-). The transverse momentum distributions are obtained for various centrality intervals in the p(T) range of 0.4-16 GeV/c. Measurements of integrated yields, mean transverse momenta, and particle yield ratios are reported and found to be consistent with previous ALICE measurements for K *(892)(0) within uncertainties. The p(T)-integrated yield ratio 2 K*(892)(+/-)/(K+ + K-) in central Pb-Pb collisions shows a significant suppression at a level of 9.3 sigma relative to pp collisions. Thermal model calculations result in an overprediction of the particle yield ratio. Although both hadron resonance gas in partial chemical equilibrium (HRG-PCE) and MUSIC + SMASH simulations consider the hadronic phase, only HRG-PCE accurately represents the measurements, whereas MUSIC + SMASH simulations tend to overpredict the particle yield ratio. These observations, along with the kinetic freeze-out temperatures extracted from the yields measured for light-flavored hadrons using the HRG-PCE model, indicate a finite hadronic phase lifetime, which decreases with increasing collision centrality percentile. The p(T)-differential yield ratios 2 K*(892)(+/-)/(K+ + K-) and 2 K *(892)(+/-) /( pi(+) + pi(-)) are presented and compared with measurements in pp collisions at root s = 5.02 TeV. Both particle ratios are found to be suppressed by up to a factor of five at p(T) < 2.0 GeV/c in central Pb-Pb collisions and are qualitatively consistent with expectations for rescattering effects in the hadronic phase. The nuclear modification factor (R-AA) shows a smooth evolution with centrality and is found to be below unity at p(T) > 8 GeV/c, consistent with measurements for other light-flavored hadrons. The smallest values are observed in most central collisions, indicating larger energy loss of partons traversing the dense medium.