Production of $${{\overline \Sigma }^{ \pm }}$$ Baryons in p–Pb and pp Collisions at the LHC with ALICE

This work presents novel measurements of charged $$\\Sigma $$ hyperons by the ALICE collaboration, with a particular emphasis on a new reconstruction technique for the decay channel $${{\\overline \\Sigma }^{ \\pm }} \\to \\overline n {{\\pi }^{ \\pm }}$$ . The core of our analysis is a pioneering method for detecting anti-neutrons using the photon spectrometer (PHOS). This approach overcomes the significant experimental challenge of reconstructing neutral particles by capitalizing on the characteristic hadronic showers produced by anti-neutrons upon annihilation in the electromagnetic calorimeter. The identification of the accompanying charged pion ( $${{\\pi }^{ \\pm }}$$ ) completes the reconstruction of the $${{\\overline \\Sigma }^{ \\pm }}$$ decay vertex. We report the transverse momentum ( $${{p}_{{\\text{T}}}}$$ ) spectra of $${{\\overline \\Sigma }^{ \\pm }}$$ hyperons in minimum bias pp and p–Pb collisions at $$\\sqrt {{{s}_{{NN}}}} = 5.02$$ TeV, the nuclear modification factor $${{R}_{{{\\text{pPb}}}}}$$ , and $${{\\overline \\Sigma }^{ + }}{\\kern 1pt} /{\\kern 1pt} {{\\overline \\Sigma }^{ - }}$$ ratios. These results are compared with predictions from state-of-the-art Monte Carlo event generators to test their description of strangeness production.