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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.

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.

Recent measurements of charm-baryon production in hadronic collisions have questioned the universality of charm-quark fragmentation across different collision systems. In this work the fragmentation of charm quarks into charm baryons is probed, by presenting the first measurement of the longitudinal jet momentum fraction carried by${\mathrm{\Lambda }}_c^{+}$baryons,$z_{\parallel }^{\mathrm{ch}}$, in hadronic collisions. The results are obtained in proton-proton ($pp$) collisions at$\sqrt{s}=13\mathrm{TeV}$at the LHC, with${\mathrm{\Lambda }}_c^{+}$baryons and charged (track-based) jets reconstructed in the transverse momentum intervals of$3\le p_T^{{\mathrm{\Lambda }}_c^{+}}<15\mathrm{GeV}/c$and$7\le p_T^{\text{jet ch}}<15\mathrm{GeV}/c$, respectively. The$z_{\parallel }^{\mathrm{ch}}$distribution is compared to a measurement of${\mathrm{D}}^0$-tagged charged jets in$pp$collisions as well as to 8 simulations. The data hints that the fragmentation of charm quarks into charm baryons is softer with respect to charm mesons, in the measured kinematic interval, as predicted by hadronization models which include color correlations beyond leading-color in the string formation.

A Large Ion Collider Experiment (ALICE) has been conceived and constructed as a heavy-ion experiment at the LHC. During LHC Runs 1 and 2, it has produced a wide range of physics results using all collision systems available at the LHC. In order to best exploit new physics opportunities opening up with the upgraded LHC and new detector technologies, the experiment has undergone a major upgrade during the LHC Long Shutdown 2 (2019–2022). This comprises the move to continuous readout, the complete overhaul of core detectors, as well as a new online event processing farm with a redesigned online-offline software framework. These improvements will allow to record Pb-Pb collisions at rates up to 50 kHz, while ensuring sensitivity for signals without a triggerable signature.

The first measurement of the cross section for incoherent photonuclear production of$J/\psi$vector mesons as a function of the Mandelstam$|t|$variable is presented. The measurement was carried out with the ALICE detector at midrapidity,$|y|<0.8$, using ultraperipheral collisions of Pb nuclei at a center-of-mass energy per nucleon pair of$\sqrt{s_{\mathrm{NN}}}=5.02\mathrm{TeV}$. This rapidity interval corresponds to a Bjorken-$x$range$(0.3–1.4)\times {10}^{-3}$. Cross sections are given in five$|t|$intervals in the range$0.04<|t|<1{\mathrm{GeV}}^2$and compared to the predictions by different models. Models that ignore quantum fluctuations of the gluon density in the colliding hadron predict a$|t|$dependence of the cross section much steeper than in data. The inclusion of such fluctuations in the same models provides a better description of the data.