ALICE

Understanding the production mechanism of light (anti)nuclei is one of the key challenges of nuclear physics and has important consequences for astrophysics, since it provides an input for indirect dark-matter searches in space. In this paper, the latest results about the production of light (anti)nuclei in pp collisions at $ \sqrt{s} $ = 13 TeV are presented, focusing on the comparison with the predictions of coalescence and thermal models [...]

ALICE (A Large Ion Collider Experiment) collected over two billion proton-proton collision events at a center-of-mass energy of 13 TeV during the second running period (from 2016 to 2018) of the Large Hadron Collider (LHC). This rich data sample allows for studies of at this collision energy rarely produced objects, such as light nuclei. [...]

Collective behaviour of final-state hadrons, and multiparton interactions are studied in high-multiplicity ep scattering at a centre-of-mass energy $ \sqrt{s} $ = 318 GeV with the ZEUS detector at HERA. Two- and four-particle azimuthal correlations, as well as multiplicity, transverse momentum, and pseudorapidity distributions for charged-particle multiplicities N$_{ch}$ ≥ 20 are measured. [...]

We study the influence of global baryon number conservation on the non-critical baseline of net baryon cumulants in heavy-ion collisions in a given acceptance, accounting for the asymmetry between the mean-numbers of baryons and antibaryons. We derive the probability distribution of net baryon number in a restricted phase space from the canonical partition function that incorporates exact conservation of baryon number in the full system. [...]

The coherent photoproduction of $\rm{J/\psi}$ and $\rm{\psi'}$ mesons was measured in ultra-peripheral Pb-Pb collisions at a center-of-mass energy $\sqrt{s_{\mathrm{NN}}}~=~5.02$ TeV with the ALICE detector. Charmonia are detected in the central rapidity region for events where the hadronic interactions are strongly suppressed. [...]

The first measurement of the coherent photoproduction of ρ$^0$ vector mesons in ultra-peripheral Xe–Xe collisions at $\sqrt{s_{\rm NN}}$ = 5.44 TeV is presented. This result, together with previous HERA γp data and γ–Pb measurements from ALICE, describes the atomic number (A) dependence of this process, which is particularly sensitive to nuclear shadowing effects and to the approach to the black-disc limit of QCD at a semi-hard scale. [...]

The first measurement of the production of pions, kaons, (anti-)protons and $\phi $ mesons at midrapidity in Xe–Xe collisions at $\sqrt{s_{\mathrm{NN}}} = 5.44~\text {TeV}$ is presented. Transverse momentum ($p_{\mathrm{T}}$) spectra and $p_{\mathrm{T}}$-integrated yields are extracted in several centrality intervals bridging from p–Pb to mid-central Pb–Pb collisions in terms of final-state multiplicity. [...]

The multiplicity dependence of the pseudorapidity density of charged particles in proton–proton (pp) collisions at centre-of-mass energies $\sqrt{s}~=~5.02$, 7 and 13 TeV measured by ALICE is reported. The analysis relies on track segments measured in the midrapidity range ($|\eta | < 1.5$). [...]