Extracting baryon-antibaryon strong interaction potentials from p$\bar{\Lambda}$ femtoscopic correlation function

Abstract

The STAR experiment has measured $p\Lambda$, $\bar{p}\bar{\Lambda}$, $\bar{p}\Lambda$, and $p\bar{\Lambda}$ femtoscopic correlation functions in central Au+Au collisions at $\sqrt{s_{NN}}=200$ GeV. The system size extracted for $p\Lambda$ and $\bar{p}\bar{\Lambda}$ is consistent with model expectations and results for other pair types, while for $p\bar{\Lambda}$ and $\bar{p}\Lambda$ it is not consistent with the other two and significantly lower. In addition an attempt was made to extract the unknown parameters of the strong interaction potential for this baryon-antibaryon ($B\bar{B}$) pair. In this work we reanalyze the STAR data, taking into account residual femtoscopic correlations from heavier $B\bar{B}$ pairs. We obtain new estimates for the system size, consistent with the results for $p\Lambda$ and $\bar{p}\bar{\Lambda}$ pairs and with model expectations. We give new estimates for the strong interaction potential parameters for $p\bar{\Lambda}$ and show that similar constraints can be given for parameters for other, heavier $B\bar{B}$ pairs.