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arXiv · 1509.04245

Proton-lambda correlation functions at the LHC with account for residual correlations

Abstract

The theoretical analysis of $\bar{p}-Λ\oplus p-\barΛ$ correlation function in 10% most central Au+Au collisions at RHIC energy $\sqrt{s_{NN}}=200$ GeV shows that the contribution of residual correlations is the necessary factor to obtain a satisfactory description of the experimental data. A neglecting of the residual correlation effect, leads to unrealistically low source radius, about 2 times smaller than the corresponding value for $p-Λ\oplus \bar{p}-\barΛ$ case, when one fits the experimental correlation function within Lednicky-Lyuboshitz analytical model. Recently an approach accounting effectively for residual correlations for the baryon-antibaryon correlation function was proposed, and a good RHIC data description was reached with the source radius extracted from the hydrokinetic model (HKM). The $\bar{p}-Λ$ scattering length, as well as the parameters characterizing the residual correlation effect --- annihilation dip amplitude and its inverse width --- were extracted from the corresponding fit. In this paper we use these extracted values and simulated in HKM source functions for Pb+Pb collisions at the LHC energy $\sqrt{s_{NN}}=2.76$ TeV to predict the corresponding $pΛ$ and $p\barΛ$ correlation functions.

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V. M. Shapoval, Yu. M. Sinyukov, V. Yu. Naboka. 2015-09-14. Proton-lambda correlation functions at the LHC with account for residual correlations. https://doi.org/10.1103/physrevc.92.044910

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