Abstract
The transverse momentum spectra and integrated yields of anti- $$\Sigma $$ Σ hyperons ( $$\overline{\Sigma }^{\pm } $$ Σ ¯ ± ) have been measured in $$\text {pp}$$ pp and $$\text {p}{-}\text {Pb}$$ p - Pb collisions at $$\sqrt{s_{\textrm{NN}}}=5.02$$ s NN = 5.02 TeV with the ALICE experiment. Measurements are performed via the newly accessed decay channel $$\overline{\Sigma }^{\pm } \!\!\rightarrow \mathrm{\overline{n}} \pi ^{\pm }$$ Σ ¯ ± → n ¯ π ± . A new method of antineutron reconstruction with the PHOS electromagnetic spectrometer is developed and applied to this analysis. The $$p_{\textrm{T}}$$ p T spectra of $$\overline{\Sigma }^{\pm } $$ Σ ¯ ± are measured in the range $$0.5<p_{\textrm{T}} <3$$ 0.5 < p T < 3 GeV/ $$c$$ c and compared to predictions of the PYTHIA 8, DPMJET, PHOJET, EPOS LHC and EPOS4 models. The EPOS LHC and EPOS4 models provide the best descriptions of the measured spectra both in $$\text {pp}$$ pp and $$\text {p}{-}\text {Pb}$$ p - Pb collisions, while models which do not account for multiparton interactions provide a considerably worse description at high $$p_{\textrm{T}}$$ p T . The total yields of $$\overline{\Sigma }^{\pm } $$ Σ ¯ ± in both