$K^{-}p$ Correlation Function from High-Energy Nuclear Collisions and Chiral SU(3) Dynamics

The two-particle momentum correlation function of a $K^{-}p$ pair from high-energy nuclear collisions is evaluated in the $\overline{K}N\text{−}\pi \mathrm{\Sigma }\text{−}\pi \mathrm{\Lambda }$ coupled-channel framework. The effects of all coupled channels together with the Coulomb potential and the threshold energy difference between $K^{-}p$ and ${\overline{K}}^{0}n$ are treated completely for the first time. Realistic potentials based on the chiral SU(3) dynamics are used which fit the available scattering data. The recently measured correlation function is found to be well reproduced by allowing variations of the source size and the relative weight of the source function of $\pi \mathrm{\Sigma }$ with respect to that of $\overline{K}N$. The predicted $K^{-}p$ correlation function from larger systems indicates that the investigation of its source size dependence is useful in providing further constraints in the study of the $\overline{K}N$ interaction.

Figure 1

$K^{-}p$ correlation function with $R=1\mathrm{fm}$ (upper panel) and $R=3\mathrm{fm}$ (lower panel). The long-dashed line denotes the result with $K^{-}p$ component only. The short-dashed, dotted, and solid lines show the results in which the contributions from ${\overline{K}}^{0}n$, ${\overline{K}}^{0}n$, and $\pi \mathrm{\Sigma }$, and from all coupled-channel components are added, respectively. The dash-dotted line denotes the full coupled-channel calculation without the Coulomb interaction.

Figure 2

Reduced ${\chi }^2$ distribution in the $(R,{\omega }_{\pi \mathrm{\Sigma }})$ plane. From inward out the contour lines correspond to ${\chi }^2/\mathrm{d}.\mathrm{o}.\mathrm{f}.=0.5$, 1, 1.5, and 2, respectively.

Figure 3

Correlation function with the best fit parameters (solid line). The result including the $\mathrm{\Lambda }(1520)$ contribution is shown by the dotted line. The dashed line shows the prediction with $R=1.6\mathrm{fm}$. Its shaded area shows the uncertainty with respect to the variation of ${\omega }_{\pi \mathrm{\Sigma }}$. For comparison, we also plot the corresponding area for the case with $R=0.9\mathrm{fm}$. The ALICE data set is taken from Ref. [20].