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This article reports measurements of the angle between differently defined jet axes in pp collisions at $$ \sqrt{s} $$ s = 5.02 TeV carried out by the ALICE Collaboration. Charged particles at midrapidity are clustered into jets with resolution parameters R = 0.2 and 0.4. The jet axis, before and after Soft Drop grooming, is compared to the jet axis from the Winner-Takes-All (WTA) recombination scheme. The angle between these axes, ∆Raxis, probes a wide phase space of the jet formation and evolution, ranging from the initial high-momentum-transfer scattering to the hadronization process. The ∆Raxis observable is presented for 20 <$$ {p}_{\textrm{T}}^{\textrm{ch}\ \textrm{jet}} $$ p T ch jet < 100 GeV/c, and compared to predictions from the PYTHIA 8 and Herwig 7 event generators. The distributions can also be calculated analytically with a leading hadronization correction related to the non-perturbative component of the Collins-Soper-Sterman (CSS) evolution kernel. Comparisons to analytical predictions at next-to-leading-logarithmic accuracy with leading hadronization correction implemented from experimental extractions of the CSS kernel in Drell-Yan measurements are presented. The analytical predictions describe the measured data within 20% in the perturbative regime, with surprising agreement in the non-perturbative regime as well. These results are compatible with the universality of the CSS kernel in the context of jet substructure.

The azimuthal ($$\Delta \varphi $$ Δ φ ) correlation distributions between heavy-flavor decay electrons and associated charged particles are measured in pp and p–Pb collisions at $$\sqrt{s_{\mathrm{{NN}}}} = 5.02$$ s NN = 5.02 TeV. Results are reported for electrons with transverse momentum $$4<p_{\textrm{T}}<16$$ 4 < p T < 16 $$\textrm{GeV}/c$$ GeV / c  and pseudorapidity $$|\eta |<0.6$$ | η | < 0.6 . The associated charged particles are selected with transverse momentum $$1<p_{\textrm{T}}<7$$ 1 < p T < 7 $$\textrm{GeV}/c$$ GeV / c , and relative pseudorapidity separation with the leading electron $$|\Delta \eta | < 1$$ | Δ η | < 1 . The correlation measurements are performed to study and characterize the fragmentation and hadronization of heavy quarks. The correlation structures are fitted with a constant and two von Mises functions to obtain the baseline and the near- and away-side peaks, respectively. The results from p–Pb collisions are compared with those from pp collisions to study the effects of cold nuclear matter. In the measured trigger electron and associated particle kinematic regions, the two collision systems give consistent results. The $$\Delta \varphi $$ Δ φ distribution and the peak observables in pp and p–Pb collisions are compared with calculations from various Monte Carlo event generators.

The production of strange hadrons ($$ {\textrm{K}}_{\textrm{S}}^0 $$ K S 0 , Λ, Ξ±, and Ω±), baryon-to-meson ratios (Λ/$$ {\textrm{K}}_{\textrm{S}}^0 $$ K S 0 , Ξ/$$ {\textrm{K}}_{\textrm{S}}^0 $$ K S 0 , and Ω/$$ {\textrm{K}}_{\textrm{S}}^0 $$ K S 0 ), and baryon-to-baryon ratios (Ξ/Λ, Ω/Λ, and Ω/Ξ) associated with jets and the underlying event were measured as a function of transverse momentum (pT) in pp collisions at $$ \sqrt{s} $$ s = 13 TeV and p Pb collisions at $$ \sqrt{s_{\textrm{NN}}} $$ s NN = 5.02 TeV with the ALICE detector at the LHC. The inclusive production of the same particle species and the corresponding ratios are also reported. The production of multi-strange hadrons, Ξ± and Ω±, and their associated particle ratios in jets and in the underlying event are measured for the first time. In both pp and p–Pb collisions, the baryon-to-meson and baryon-to-baryon yield ratios measured in jets differ from the inclusive particle production for low and intermediate hadron pT (0.6–6 GeV/c). Ratios measured in the underlying event are in turn similar to those measured for inclusive particle production. In pp collisions, the particle production in jets is compared with Pythia 8 predictions with three colour-reconnection implementation modes. None of them fully reproduces the data in the measured hadron pT region. The maximum deviation is observed for Ξ± and Ω± which reaches a factor of about six. The event multiplicity dependence is further investigated in p−Pb collisions. In contrast to what is observed in the underlying event, there is no significant event-multiplicity dependence for particle production in jets. The presented measurements provide novel constraints on hadronisation and its Monte Carlo description. In particular, they demonstrate that the fragmentation of jets alone is insufficient to describe the strange and multi-strange particle production in hadronic collisions at LHC energies.