Constraining the $\overline{\mathrm{K}}\mathrm{N}$ coupled channel dynamics using femtoscopic correlations at the LHC

Abstract

The interaction of ${\mathrm{K}}^{-}$ with protons is characterised by the presence of several coupled channels, systems like ${\overline{\mathrm{K}}}^0$n and $\pi \Sigma$ with a similar mass and the same quantum numbers as the ${\mathrm{K}}^{-}$p state. The strengths of these couplings to the ${\mathrm{K}}^{-}$p system are of crucial importance for the understanding of the nature of the $\Lambda (1405)$ resonance and of the attractive ${\mathrm{K}}^{-}$p strong interaction. In this article, we present measurements of the ${\mathrm{K}}^{-}$p correlation functions in relative momentum space obtained in pp collisions at $\sqrt{s}=13$ TeV, in p-Pb collisions at $\sqrt{s_{\mathrm{NN}}}=5.02$ TeV, and (semi)peripheral Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}}=5.02$ TeV. The emitting source size, composed of a core radius anchored to the ${\mathrm{K}}^{+}$p correlation and of a resonance halo specific to each particle pair, varies between 1 and 2 fm in these collision systems. The strength and the effects of the ${\overline{\mathrm{K}}}^0$n and $\pi \Sigma$ inelastic channels on the measured ${\mathrm{K}}^{-}$p correlation function are investigated in the different colliding systems by comparing the data with state-of-the-art models of chiral potentials. A novel approach to determine the conversion weights $\omega$, necessary to quantify the amount of produced inelastic channels in the correlation function, is presented. In this method, particle yields are estimated from thermal model predictions, and their kinematic distribution from blast-wave fits to measured data. The comparison of chiral potentials to the measured ${\mathrm{K}}^{-}$p interaction indicates that, while the $\pi \Sigma -{\mathrm{K}}^{-}$p dynamics is well reproduced by the model, the coupling to the ${\overline{\mathrm{K}}}^0$n channel in the model is currently underestimated.

30 pages, 7 captioned figures, 4 tables, authors from page 24, published version, figures at http://alice-publications.web.cern.ch/node/8223

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• Effective Kbar N interaction based on chiral SU(3) dynamics
• K^- p scattering length from scattering experiments
• Lattice QCD Evidence that the Lambda(1405) Resonance is an Antikaon-Nucleon Molecule
• Constraints on the chiral unitary $\bar{K}N$ amplitude from $\pi \Sigma K^{+}$ photoproduction data
• Lineshape of the Lambda(1405) Hyperon Measured Through its Sigma0 pion0 Decay
• Two-pole structures in QCD: Facts, not fantasy!
• Generalized weak-binding relations of compositeness in effective field theory

Cited by in corpus (8)

• The ALICE experiment: a journey through QCD
• Two-pole nature of the $\Lambda (1405)$ from lattice QCD
• Lattice QCD study of $\pi \Sigma -\bar{K}N$ scattering and the $\Lambda (1405)$ resonance
• Studying the interaction between charm and light-flavor mesons
• Novel model for particle emission in small collision systems
• Study of the p$-$p$-$K${}^{+}$ and p$-$p$-$K${}^{-}$ dynamics using the femtoscopy technique
• Pole trajectories of the $\Lambda (1405)$ helps establish its dynamical nature
• Searching for femtoscopic signatures of the $D\bar{D}(I=0)[X(3700)]$ bound state