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Abstract The transverse momentum spectra and integrated yields of anti-$$\Sigma $$ hyperons ($$\overline{\Sigma }^{\pm } $$ ) have been measured in$$\text {pp}$$ and$$\text {p}{-}\text {Pb}$$ collisions at$$\sqrt{s_{\textrm{NN}}}=5.02$$ TeV with the ALICE experiment. Measurements are performed via the newly accessed decay channel$$\overline{\Sigma }^{\pm } \!\!\rightarrow \mathrm{\overline{n}} \pi ^{\pm }$$ . A new method of antineutron reconstruction with the PHOS electromagnetic spectrometer is developed and applied to this analysis. The$$p_{\textrm{T}}$$ spectra of$$\overline{\Sigma }^{\pm } $$ are measured in the range$$0.5<3$$ GeV/$$c$$ 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$$\text {pp}$$ and$$\text {p}{-}\text {Pb}$$ collisions, while models which do not account for multiparton interactions provide a considerably worse description at high$$p_{\textrm{T}}$$ . The total yields of$$\overline{\Sigma }^{\pm } $$ in both$$\text {pp}$$ and$$\text {p}{-}\text {Pb}$$ collisions are compared to predictions of the Thermal-FIST model and dynamical models PYTHIA 8, DPMJET, PHOJET, EPOS LHC and EPOS4. All models reproduce the total yields in both colliding systems within uncertainties. The nuclear modification factors$$R_\textrm{pPb}$$ for both$$\overline{\Sigma }^{+} $$ and$$\overline{\Sigma }^{-} $$ are evaluated and compared to those of protons,$$\Lambda $$ and$$\Xi $$ hyperons, and predictions of EPOS LHC and EPOS4 models. No deviations of$$R_\textrm{pPb}$$ for$$\overline{\Sigma }^{\pm } $$ from the model predictions or measurements for other hadrons are found within uncertainties.
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Study of the p–p–K$$^{+}$$ and p–p–K$$^{-}$$ dynamics using the femtoscopy technique
Abstract The interactions of kaons (K) and antikaons ($$\mathrm {\overline{K}}$$ ) with few nucleons (N) were studied so far using kaonic atom data and measurements of kaon production and interaction yields in nuclei. Some details of the three-body KNN and$$\mathrm {\overline{K}}$$ NN dynamics are still not well understood, mainly due to the overlap with multi-nucleon interactions in nuclei. An alternative method to probe the dynamics of three-body systems with kaons is to study the final state interaction within triplet of particles emitted in pp collisions at the Large Hadron Collider, which are free from effects due to the presence of bound nucleons. This Letter reports the first femtoscopic study of p–p–K$$^+$$ and p–p–K$$^-$$ correlations measured in high-multiplicity pp collisions at$$\sqrt{s}$$ = 13 TeV by the ALICE Collaboration. The analysis shows that the measured p–p–K$$^+$$ and p–p–K$$^-$$ correlation functions can be interpreted in terms of pairwise interactions in the triplets, indicating that the dynamics of such systems is dominated by the two-body interactions without significant contributions from three-body effects or bound states.
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- PAR ID:
- 10514270
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- link.springer.com
- Date Published:
- Journal Name:
- The European Physical Journal A
- Volume:
- 59
- Issue:
- 12
- ISSN:
- 1434-601X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript
- Journal Article:
- https://doi.org/10.1140/epja/s10050-023-01139-9
