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Deuterons are atomic nuclei composed of a neutron and a proton held together by the strong interaction. Unbound ensembles composed of a deuteron and a third nucleon have been investigated in the past using scattering experiments, and they constitute a fundamental reference in nuclear physics to constrain nuclear interactions and the properties of nuclei. In this work, $K^{+}\text{−}d$and $p\text{−}d$femtoscopic correlations measured by the ALICE Collaboration in proton-proton ( $pp$) collisions at $\sqrt{s}=13\mathrm{TeV}$at the Large Hadron Collider (LHC) are presented. It is demonstrated that correlations in momentum space between deuterons and kaons or protons allow us to study three-hadron systems at distances comparable with the proton radius. The analysis of the $K^{+}\text{−}d$correlation shows that the relative distances at which deuterons and protons or kaons are produced are around 2 fm. The analysis of the $p\text{−}d$correlation shows that only a full three-body calculation that accounts for the internal structure of the deuteron can explain the data. In particular, the sensitivity of the observable to the short-range part of the interaction is demonstrated. These results indicate that correlations involving light nuclei in $pp$collisions at the LHC will also provide access to any three-body system in the strange and charm sectors. Published by the American Physical Society2024 

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. 

Abstract The ALICE experiment was proposed in 1993, to study strongly-interacting matter at extreme energy densities and temperatures. This proposal entailed a comprehensive investigation of nuclear collisions at the LHC. Its physics programme initially focused on the determination of the properties of the quark–gluon plasma (QGP), a deconfined state of quarks and gluons, created in such collisions. The ALICE physics programme has been extended to cover a broader ensemble of observables related to Quantum Chromodynamics (QCD), the theory of strong interactions. The experiment has studied Pb–Pb, Xe–Xe, p–Pb and pp collisions in the multi-TeV centre of mass energy range, during the Run 1–2 data-taking periods at the LHC (2009–2018). The aim of this review is to summarise the key ALICE physics results in this endeavor, and to discuss their implications on the current understanding of the macroscopic and microscopic properties of strongly-interacting matter at the highest temperatures reached in the laboratory. It will review the latest findings on the properties of the QGP created by heavy-ion collisions at LHC energies, and describe the surprising QGP-like effects in pp and p–Pb collisions. Measurements of few-body QCD interactions, and their impact in unraveling the structure of hadrons and hadronic interactions, will be discussed. ALICE results relevant for physics topics outside the realm of QCD will also be touched upon. Finally, prospects for future measurements with the ALICE detector in the context of its planned upgrades will also be briefly described. 

A<sc>bstract</sc> The production yields of the Σ(1385)^±and Ξ(1530)⁰resonances are measured in pp collisions at$$ \sqrt{s} $$ $\sqrt{s}$= 13 TeV with ALICE. The measurements are performed as a function of the charged-particle multiplicity ⟨dN_ch/dη⟩, which is related to the energy density produced in the collision. The results include transverse momentum (p_T) distributions,p_T-integrated yields, mean transverse momenta of Σ(1385)^±and Ξ(1530)⁰, as well as ratios of thep_T-integrated resonance yields relative to yields of other hadron species. The Σ(1385)^±/π^±and Ξ(1530)⁰/π^±yield ratios are consistent with the trend of the enhancement of strangeness production from low to high multiplicity pp collisions, which was previously observed for strange and multi-strange baryons. The yield ratio between the measured resonances and the long-lived baryons with the same strangeness content exhibits a hint of a mild increasing trend at low multiplicity, despite too large uncertainties to exclude the flat behaviour. The results are compared with predictions from models such as EPOS-LHC and PYTHIA 8 with Rope shoving. The latter provides the best description of the multiplicity dependence of the Σ(1385)^±and Ξ(1530)⁰production in pp collisions at$$ \sqrt{s} $$ $\sqrt{s}$= 13 TeV. 

A<sc>bstract</sc> Measurements of inclusive charged-particle jet production in pp and p-Pb collisions at center-of-mass energy per nucleon-nucleon collision$$ \sqrt{s_{\textrm{NN}}} $$ $\sqrt{s_{\mathrm{NN}}}$= 5.02 TeV and the corresponding nuclear modification factor$$ {R}_{\textrm{pPb}}^{\textrm{ch}\ \textrm{jet}} $$ $R_{\mathrm{pPb}}^{\mathrm{ch}\mathrm{jet}}$are presented, using data collected with the ALICE detector at the LHC. Jets are reconstructed in the central rapidity region |η_jet|<0.5 from charged particles using the anti-k_Talgorithm with resolution parametersR= 0.2, 0.3, and 0.4. Thep_T-differential inclusive production cross section of charged-particle jets, as well as the corresponding cross section ratios, are reported for pp and p-Pb collisions in the transverse momentum range 10<$$ {p}_{\textrm{T},\textrm{jet}}^{\textrm{ch}} $$ $p_{T,\mathrm{jet}}^{\mathrm{ch}}$<140 GeV/cand 10<$$ {p}_{\textrm{T},\textrm{jet}}^{\textrm{ch}} $$ $p_{T,\mathrm{jet}}^{\mathrm{ch}}$<160 GeV/c, respectively, together with the nuclear modification factor$$ {R}_{\textrm{pPb}}^{\textrm{ch}\ \textrm{jet}} $$ $R_{\mathrm{pPb}}^{\mathrm{ch}\mathrm{jet}}$in the range 10<$$ {p}_{\textrm{T},\textrm{jet}}^{\textrm{ch}} $$ $p_{T,\mathrm{jet}}^{\mathrm{ch}}$<140 GeV/c. The analysis extends thep_Trange of the previously-reported charged-particle jet measurements by the ALICE Collaboration. The nuclear modification factor is found to be consistent with one and independent of the jet resolution parameter with the improved precision of this study, indicating that the possible influence of cold nuclear matter effects on the production cross section of charged-particle jets in p-Pb collisions at$$ \sqrt{s_{\textrm{NN}}} $$ $\sqrt{s_{\mathrm{NN}}}$= 5.02 TeV is smaller than the current precision. The obtained results are in agreement with other minimum bias jet measurements available for RHIC and LHC energies, and are well reproduced by the NLO perturbative QCD Powhegcalculations with parton shower provided by Pythia8 as well as by Jetscapesimulations. 

A<sc>bstract</sc> The ALICE Collaboration reports a search for jet quenching effects in high-multiplicity (HM) proton-proton collisions at$$ \sqrt{s} $$ $\sqrt{s}$= 13 TeV, using the semi-inclusive azimuthal-difference distribution ∆φof charged-particle jets recoiling from a high transverse momentum (high-p_T,trig) trigger hadron. Jet quenching may broaden the ∆φdistribution measured in HM events compared to that in minimum bias (MB) events. The measurement employs ap_T,trig-differential observable for data-driven suppression of the contribution of multiple partonic interactions, which is the dominant background. While azimuthal broadening is indeed observed in HM compared to MB events, similar broadening for HM events is observed for simulations based on the PYTHIA 8 Monte Carlo generator, which does not incorporate jet quenching. Detailed analysis of these data and simulations show that the azimuthal broadening is due to bias of the HM selection towards events with multiple jets in the final state. The identification of this bias has implications for all jet quenching searches where selection is made on the event activity.