Dataset

GSI-2023-00180

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png Exploring the N$\Lambda$-N$\Sigma$ coupled system with high precision correlation techniques at the LHC

ALICE Collaboration (Corresponding author)

2022

Please use a persistent id in citations: doi:10.17182/HEPDATA.131625

Abstract: The interaction of $\Lambda$ and $\Sigma$ hyperons (Y) with nucleons (N) is strongly influenced by the coupled-channel dynamics. Due to the small mass difference of the N$\Lambda$ and N$\Sigma$ systems, the sizable coupling strength of the N$\Sigma\leftrightarrow$N$\Lambda$ processes constitutes a crucial element in the determination of the N$\Lambda$ interaction. In this letter we present the most precise measurements on the interaction of p$\Lambda$ pairs, from zero relative momentum up to the opening of the N$\Sigma$ channel. The correlation function in the relative momentum space for p$\Lambda\oplus\overline{\mathrm{p}}\overline{\Lambda}$ pairs measured in high-multiplicity triggered pp collisions at $\sqrt{s}=13~$TeV at the LHC is reported. The opening of the inelastic N$\Sigma$ channels is visible in the extracted correlation function as a cusp-like structure occurring at relative momentum {$k^*=289~$MeV$/c$}. This represents the first direct experimental observation of the N$\Sigma\rightarrow$N$\Lambda$ coupled channel in the p$\Lambda$ system. The correlation function is compared with recent chiral effective field theory calculations, based on different strengths of the N$\Sigma\leftrightarrow$N$\Lambda$ transition potential. A weaker coupling, as possibly supported by the present measurement, would require a more repulsive three-body NN$\Lambda$ interaction for a proper description of the $\Lambda$ in-medium properties, which has implications on the nuclear equation of state and for the presence of hyperons inside neutron stars.

Note: Journal Article GSI record: GSI-2023-00133

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Contributing Institute(s):

1. ALICE (ALI)
2. Detektorlabor (DTL)
3. IT (CIT)
4. ExtreMe Matter Institute, EMMI (EXM)
5. Collaboration CERN: ALICE (ALICE@CERN)

Research Program(s):

1. 612 - Cosmic Matter in the Laboratory (POF4-612) (POF4-612)
2. HGS-HIRe - HGS-HIRe for FAIR (HGS-HIRe) (HGS-HIRe)
3. SUC-GSI-Heidelberg - Strategic university cooperation GSI-U Heidelberg (SUC-GSI-HE) (SUC-GSI-HE)
4. SUC-GSI-Frankfurt - Strategic university cooperation GSI-U Frankfurt/M (SUC-GSI-FR) (SUC-GSI-FR)
5. SUC-GSI-Darmstadt - Strategic university cooperation GSI-TU Darmstadt (SUC-GSI-DA) (SUC-GSI-DA)

Experiment(s):

1. LHC: ALICE

Appears in the scientific report 2022

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Linked articles:

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png Journal Article Acharya, S. ; Adamova, D. ; Adler, A. ; et al
Exploring the NΛ–NΣ coupled system with high precision correlation techniques at the LHC
Physics letters / B 833, 137272 (2022) [10.1016/j.physletb.2022.137272]2022   Files  Fulltext by arXiv.org BibTeX | EndNote: XML, Text | RIS

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