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A<sc>bstract</sc> Correlations in azimuthal angle extending over a long range in pseudorapidity between particles, usually called the “ridge” phenomenon, were discovered in heavy-ion collisions, and later found in pp and p–Pb collisions. In large systems, they are thought to arise from the expansion (collective flow) of the produced particles. Extending these measurements over a wider range in pseudorapidity and final-state particle multiplicity is important to understand better the origin of these long-range correlations in small collision systems. In this Letter, measurements of the long-range correlations in p–Pb collisions at$$ \sqrt{s_{\textrm{NN}}} $$ $\sqrt{s_{\mathrm{NN}}}$= 5.02 TeV are extended to a pseudorapidity gap of ∆η~ 8 between particles using the ALICE forward multiplicity detectors. After suppressing non-flow correlations, e.g., from jet and resonance decays, the ridge structure is observed to persist up to a very large gap of ∆η~ 8 for the first time in p–Pb collisions. This shows that the collective flow-like correlations extend over an extensive pseudorapidity range also in small collision systems such as p–Pb collisions. The pseudorapidity dependence of the second-order anisotropic flow coefficient,v₂(η), is extracted from the long-range correlations. Thev₂(η) results are presented for a wide pseudorapidity range of –3.1< η <4.8 in various centrality classes in p–Pb collisions. To gain a comprehensive understanding of the source of anisotropic flow in small collision systems, thev₂(η) measurements are compared with hydrodynamic and transport model calculations. The comparison suggests that the final-state interactions play a dominant role in developing the anisotropic flow in small collision systems. 

A<sc>bstract</sc> The Chiral Magnetic Wave (CMW) phenomenon is essential to provide insights into the strong interaction in QCD, the properties of the quark-gluon plasma, and the topological characteristics of the early universe, offering a deeper understanding of fundamental physics in high-energy collisions. Measurements of the charge-dependent anisotropic flow coefficients are studied in Pb-Pb collisions at center-of-mass energy per nucleon-nucleon collision$$ \sqrt{s_{\textrm{NN}}} $$ $\sqrt{s_{\mathrm{NN}}}$= 5.02 TeV to probe the CMW. In particular, the slope of the normalized difference in elliptic (v₂) and triangular (v₃) flow coefficients of positively and negatively charged particles as a function of their event-wise normalized number difference, is reported for inclusive and identified particles. The slope$$ {r}_3^{\textrm{Norm}} $$ $r_3^{\text{Norm}}$is found to be larger than zero and to have a magnitude similar to$$ {r}_2^{\textrm{Norm}} $$ $r_2^{\text{Norm}}$, thus pointing to a large background contribution for these measurements. Furthermore,$$ {r}_2^{\textrm{Norm}} $$ $r_2^{\text{Norm}}$can be described by a blast wave model calculation that incorporates local charge conservation. In addition, using the event shape engineering technique yields a fraction of CMW (f_CMW) contribution to this measurement which is compatible with zero. This measurement provides the very first upper limit forf_CMW, and in the 10–60% centrality interval it is found to be 26% (38%) at 95% (99.7%) confidence level.