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This paper presents the first measurement of the angle between different jet axes (denoted as $\mathrm{\Delta }{R}_{\mathrm{axis}}$ ) in $\text{Pb-Pb}$ collisions. The measurement is carried out in the 0–10 % most-central events at $\sqrt{s_{NN}}=5.02$ TeV. Jets are assembled by clustering charged particles at midrapidity using the $\text{anti-}{k}_{\mathrm{T}}$ algorithm with resolution parameters $R=0.2$ and 0.4 and transverse momenta in the intervals $40<p_{\mathrm{T}}^{\mathrm{ch}\mathrm{jet}}<140\mathrm{GeV}/c$ and $80<p_{\mathrm{T}}^{\mathrm{ch}\mathrm{jet}}<140\mathrm{GeV}/c$ , respectively. Measurements at these low transverse momenta enhance the sensitivity to quark-gluon plasma (QGP) effects. A comparison to models implementing various mechanisms of jet energy loss in the QGP suggests that the observed narrowing of the $\text{Pb-Pb}$ distribution relative to $\mathit{pp}$ can be explained if quark-initiated jets are more likely to emerge from the medium than gluon-initiated jets. These new measurements disfavor intrajet $p_{\mathrm{T}}$ broadening as implemented in a simple model calculation with the Baier-Dokshitzer-Mueller-Peigne-Schiff formalism for energy loss in the QGP. The comparison of $\text{Pb-Pb}$ and $\mathit{pp}$ collisions shows sensitivity to the angular scale at which the QGP can resolve two independent splittings, favoring mechanisms that incorporate incoherent energy loss. 

A<sc>bstract</sc> The azimuthal anisotropy of particles associated with jets (jet particles) at midrapidity is measured for the first time in p-Pb and Pb-Pb collisions at$$ \sqrt{{\textrm{s}}_{\textrm{NN}}} $$ $\sqrt{s_{\mathrm{NN}}}$ = 5.02 TeV down to transverse momentum (p_T) of 0.5 GeV/cand 2 GeV/c, respectively, with ALICE. The results obtained in p-Pb collisions are based on a novel three-particle correlation technique. The azimuthal anisotropy coefficientv₂in high-multiplicity p-Pb collisions is positive, with a significance reaching 6.8σat lowp_T, and its magnitude is smaller than in semicentral Pb-Pb collisions. In contrast to the measurements in Pb-Pb collisions, thev₂coefficient is also found independent ofp_Twithin uncertainties. Comparisons with the inclusive charged-particlev₂and with AMPT calculations are discussed. The predictions suggest that parton interactions play an important role in generating a non-zero jet-particlev₂in p-Pb collisions, even though they overestimate the reported measurement. These observations shed new insights on the understanding of the origin of the collective behaviour of jet particles in small systems such as p-Pb collisions, and provide significant stringent new constraints to models.