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Anisotropic flow of identified hadrons in Xe-Xe collisions at \( \sqrt{s_{\mathrm{NN}}} \) = 5.44 TeV

A preprint version of the article is available at arXiv.

Abstract

Measurements of elliptic (v2) and triangular (v3) flow coefficients of π±, K±, p+\( \overline{\mathrm{p}} \), \( {\mathrm{K}}_{\mathrm{S}}^0 \), and Λ+\( \overline{\Lambda} \) obtained with the scalar product method in Xe-Xe collisions at \( \sqrt{s_{\mathrm{NN}}} \) = 5.44 TeV are presented. The results are obtained in the rapidity range |y| < 0.5 and reported as a function of transverse momentum, pT, for several collision centrality classes. The flow coefficients exhibit a particle mass dependence for pT < 3 GeV/c, while a grouping according to particle type (i.e., meson and baryon) is found at intermediate transverse momenta (3 < pT < 8 GeV/c). The magnitude of the baryon v2 is larger than that of mesons up to pT = 6 GeV/c. The centrality dependence of the shape evolution of the pT-differential v2 is studied for the various hadron species. The v2 coefficients of π±, K±, and p+\( \overline{\mathrm{p}} \) are reproduced by MUSIC hydrodynamic calculations coupled to a hadronic cascade model (UrQMD) for pT < 1 GeV/c. A comparison with vn measurements in the corresponding centrality intervals in Pb-Pb collisions at \( \sqrt{s_{\mathrm{NN}}} \) = 5.02 TeV yields an enhanced v2 in central collisions and diminished value in semicentral collisions.

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