Investigation of the p-$\Sigma^{0}$ interaction via femtoscopy in pp collisions
Phys.Lett.B 805 (2020) 135419 , 2020.
The collaboration

Abstract (data abstract)
This Letter presents the first direct investigation of the p$-\Sigma^{0}$ interaction, using the femtoscopy technique in high-multiplicity pp collisions at $\sqrt{s} = 13$ TeV measured by the ALICE detector. The $\Sigma^{0}$ is reconstructed via the decay channel to $\Lambda\gamma$, and the subsequent decay of $\Lambda$ to p$\pi^-$. The photon is detected via the conversion in material to e$^+$e$^-$ pairs exploiting the unique capability of the ALICE detector to measure electrons at low transverse momenta. The measured p$-\Sigma^{0}$ correlation indicates a shallow strong interaction. The comparison of the data to several theoretical predictions obtained employing the Correlation Analysis Tool using the Schrödinger Equation (CATS) and the Lednický$-$Lyuboshits approach shows a reasonable agreement. The presented femtoscopic data cannot yet discriminate between different models, which is also the case for the available scattering and hypernuclei data. Nevertheless, the p$-\Sigma^{0}$ correlation function is found to be sensitive to the strong interaction, and driven by the interplay of the different spin and isospin channels. This pioneering study demonstrates the feasibility of a femtoscopic measurement in the p$-\Sigma^{0}$ channel and with the expected larger data samples in LHC Run 3 and Run 4, the p$-\Sigma^{0}$ interaction will be constrained with high precision.