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arXiv · 2611.08725

Probing the initial geometry and the onset of collectivity with anisotropic flow in light-ion collisions with ALICE at the LHC

Alexian Marc Lejeune·for the ALICE Collaboration
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Abstract

Collective behavior, traditionally associated with heavy-ion collisions, has been observed in small collision systems at the LHC. The recent oxygen-oxygen and neon-neon collisions allow to bridge the gap between small and large collision systems and to study the collectivity in well-constrained initial states. Measurements of azimuthal anisotropies are sensitive to the initial-state geometry and enable detailed investigations of the nuclear structure of $^{16}$O and $^{20}$Ne, highlighting the interplay between nuclear structure and collective dynamics in ultrarelativistic collisions. This contribution presents recent anisotropic flow measurements performed by the ALICE Collaboration in OO and Ne-Ne collisions at $\sqrt{s_{\mathrm{NN}}}$ = 5.36 TeV using two- and multiparticle correlation methods. The results are compared to hydrodynamic calculations incorporating the possible nuclear structures of these light nuclei, providing stringent constraints on the modeling of the initial state. In addition, prospects for measuring long-range correlations with the forward ALICE detectors are discussed, with the aim of studying the longitudinal dependence of anisotropic flow and thereby constraining the longitudinal structure of the initial state.

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Alexian Marc Lejeune, for the ALICE Collaboration. 2026-11-05. Probing the initial geometry and the onset of collectivity with anisotropic flow in light-ion collisions with ALICE at the LHC. https://arxiv.org/abs/2611.08725

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