We present the first measurements of femtoscopic correlations between the K$^0_{\rm S}$ and K$^{\rm \pm}$ particles in pp collisions at $\sqrt{s}=7$ TeV measured by the ALICE experiment. The observed femtoscopic correlations are consistent with final-state interactions proceeding solely via the $a_0(980)$ resonance. The extracted kaon source radius and correlation strength parameters for K$^0_{\rm S}$K$^{\rm -}$ are found to be equal within the experimental uncertainties to those for K$^0_{\rm S}$K$^{\rm +}$. Results of the present study are compared with those from identical-kaon femtoscopic studies also performed with pp collisions at $\sqrt{s}=7$ TeV by ALICE and with a K$^0_{\rm S}$K$^{\rm \pm}$ measurement in Pb-Pb collisions at $\sqrt{s_{\rm NN}}=2.76$ TeV. Combined with the Pb-Pb results, our pp analysis is found to be compatible with the interpretation of the $a_0(980)$ having a tetraquark structure instead of that of a diquark.

Measurements of energy weighted angular correlations in electron positron annihilations at c.m. energies of 22 GeV and 34 GeV are presented.

The differential cross sections for neutron-proton elastic charge-exchange scattering have been measured with a two-arm technique for incident neutron momenta between 22 and 65 GeV/ c and for values of the momentum transfer squared between 0.002 and 0.8 (GeV/ c ) 2 . The sharp forward peak observed previously at lower energies is also present at momenta up to 65 GeV/ c ; however the s dependence of the cross section is slowing down.

Coherent 3 π production on nine different nuclear targets has been studied using a 40 GeV/ c π − beam at the Serpukhov accelerator (CERN-Serpukhov experiment no. 5). The absorption in nuclear matter of the produced system has been measured, analysing the data on the different nuclear targets. Identica results are obtained from the differential cross sections and from the coherent nuclear cross sections. The 1 + waves show a very weak absorption, definitely smaller than 0 − and 2 − waves. No influence on the absorption comes from the spin-flip amplitudes, which have been found to be negligible in the coherent region.

Measurements of the double differential cross sections for ππ and pπ production in pp collisions at the CERN ISR are presented for 5 c.m. energies s = 22, 30, 44, 53, 62 GeV . Charge and transverse momentum correlations are also reported.

Transverse particle momenta have been measured ine+e− annihilation into hadrons at c.m. energies between 9.4 and 31.6 GeV. The data are fully corrected for detector effects and radiation in the initial state. A comparison is made with recent QCD calculations.

The intermediate and forward gamma detectors of EHS are used to reconstructπ°'s produced by 360 GeV/cpp interactions in the Rapid Cycling Bubble Chamber (RCBC). Using thepp forwardbackward symmetry, the inclusiveπ° production cross section is obtainedσπ°=(132±11) mb. The averageπ° multiplicity is determined as a function of the charged particle multiplicity. The (1−x) dependence is given for differentpT regions.

The analyzing powers of π+ and π− were measured using an incident 22−GeV/c transversely polarized proton beam at the Brookhaven Alternating Gradient Synchrotron. A magnetic spectrometer measured π± inclusive asymmetries on a hydrogen and a carbon target. An elastic polarimeter with a CH2 target measured pp elastic-scattering asymmetries to determine the beam polarization using published data for the pp elastic analyzing power. Using the beam polarization determined from the elastic polarimeter and asymmetries from the inclusive spectrometer, analyzing powers AN for π± were determined in the xF and pT ranges (0.45–0.8) and (0.3–1.2 GeV/c), respectively. The analyzing power results are similar in both sign and character to other measurements at 200 and 11.7 GeV/c, confirming the expectation that high-energy pion inclusive analyzing powers remain large and relatively energy independent. This suggests that pion inclusive polarimetry may be a suitable method for measuring future beam polarizations at BNL RHIC or DESY HERA. Analyzing powers of π+ and π− produced on hydrogen and carbon targets are the same. Various models to explain inclusive analyzing powers are also discussed.

The production of prompt muons ine+e− annihilation has been studied at centre of mass energies near 34.5 GeV. The measured semi-muonic branching ratios ofb andc quarks areB(b»Xμv) =0.117±0.028±0.01 andB(c→Xμv)=0.082 ±0.012a−0.01+0.02. The fragmentation functions of heavy quarks are hard, <zb>=0.85a−0.12–0.07+0.10+0.02 and <zc> =0.77a−0.07–0.11+0.05+0.03. Limits have been set on flavour changing neutral current decays:B(b→Xµ+µ−) <0.02 andB(b→Xµ+µ− (95% confidence level).

We present an analysis of electroweak leptonic couplings from high statistics experiments on Bhabha scattering and μ pair production at an energy of 34.5 GeV. The forward-backward charge asymmetry of the μ pairs was measured to be −0.098±0.023±0.005. The data were found to agree well with the standard theory of electroweak interaction giving sin2θW=0.27±0.07. The leptonic weak couplings were determined to begv=0.000±0.170 andgA=−0.481±0.055. The data were also used to investigate a class of composite models for leptons.

The production of K$^{*}$(892)$^{0}$ and $\phi$(1020) mesons has been measured in p-Pb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 5.02 TeV. K$^{*0}$ and $\phi$ are reconstructed via their decay into charged hadrons with the ALICE detector in the rapidity range $-0.5 < y <0$. The transverse momentum spectra, measured as a function of the multiplicity, have p$_{\mathrm{T}}$ range from 0 to 15 GeV/$c$ for K$^{*0}$ and from 0.3 to 21 GeV/$c$ for $\phi$. Integrated yields, mean transverse momenta and particle ratios are reported and compared with results in pp collisions at $\sqrt{s}$ = 7 TeV and Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 2.76 TeV. In Pb-Pb and p-Pb collisions, K$^{*0}$ and $\phi$ probe the hadronic phase of the system and contribute to the study of particle formation mechanisms by comparison with other identified hadrons. For this purpose, the mean transverse momenta and the differential proton-to-$\phi$ ratio are discussed as a function of the multiplicity of the event. The short-lived K$^{*0}$ is measured to investigate re-scattering effects, believed to be related to the size of the system and to the lifetime of the hadronic phase.

Three- and four-pion Bose-Einstein correlations are presented in pp, p-Pb, and Pb-Pb collisions at the LHC. We compare our measured four-pion correlations to the expectation derived from two- and three-pion measurements. Such a comparison provides a method to search for coherent pion emission. We also present mixed-charge correlations in order to demonstrate the effectiveness of several analysis procedures such as Coulomb corrections. Same-charge four-pion correlations in pp and p-Pb appear consistent with the expectations from three-pion measurements. However, the presence of non-negligible background correlations in both systems prevent a conclusive statement. In Pb-Pb collisions, we observe a significant suppression of three- and four-pion Bose-Einstein correlations compared to expectations from two-pion measurements. There appears to be no centrality dependence of the suppression within the 0-50% centrality interval. The origin of the suppression is not clear. However, by postulating either coherent pion emission or large multibody Coulomb effects, the suppression may be explained.

The elliptic, triangular, quadrangular and pentagonal anisotropic flow coefficients for $\pi^{\pm}$, $\mathrm{K}^{\pm}$ and p+$\overline{\mathrm{p}}$ in Pb-Pb collisions at $\sqrt{s_\mathrm{{NN}}} = 2.76$ TeV were measured with the ALICE detector at the Large Hadron Collider. The results were obtained with the Scalar Product method, correlating the identified hadrons with reference particles from a different pseudorapidity region. Effects not related to the common event symmetry planes (non-flow) were estimated using correlations in pp collisions and were subtracted from the measurement. The obtained flow coefficients exhibit a clear mass ordering for transverse momentum ($p_{\mathrm{T}}$) values below $\approx$ 3 GeV/$c$. In the intermediate $p_{\mathrm{T}}$ region ($3 < p_{\mathrm{T}} < 6$ GeV/$c$), particles group at an approximate level according to the number of constituent quarks, suggesting that coalescence might be the relevant particle production mechanism in this region. The results for $p_{\mathrm{T}} < 3$ GeV/$c$ are described fairly well by a hydrodynamical model (iEBE-VISHNU) that uses initial conditions generated by A Multi-Phase Transport model (AMPT) and describes the expansion of the fireball using a value of 0.08 for the ratio of shear viscosity to entropy density ($\eta/s$), coupled to a hadronic cascade model (UrQMD). Finally, expectations from AMPT alone fail to quantitatively describe the measurements for all harmonics throughout the measured transverse momentum region. However, the comparison to the AMPT model highlights the importance of the late hadronic rescattering stage to the development of the observed mass ordering at low values of $p_{\mathrm{T}}$ and of coalescence as a particle production mechanism for the particle type grouping at intermediate values of $p_{\mathrm{T}}$ for all harmonics.

Measurements of charged jet production as a function of centrality are presented for p-Pb collisions recorded at $\sqrt{s_{\rm NN}} = 5.02$ TeV with the ALICE detector. Centrality classes are determined via the energy deposit in neutron calorimeters at zero degree, close to the beam direction, to minimise dynamical biases of the selection. The corresponding number of participants or binary nucleon-nucleon collisions is determined based on the particle production in the Pb-going rapidity region. Jets have been reconstructed in the central rapidity region from charged particles with the anti-$k_{\rm T}$ algorithm for resolution parameters $R = 0.2$ and $R = 0.4$ in the transverse momentum range 20 to 120 GeV/$c$. The reconstructed jet momentum and yields have been corrected for detector effects and underlying-event background. In the five centrality bins considered, the charged jet production in p-Pb collisions is consistent with the production expected from binary scaling from pp collisions. The ratio of jet yields reconstructed with the two different resolution parameters is also independent of the centrality selection, demonstrating the absence of major modifications of the radial jet structure in the reported centrality classes.

At sufficiently high temperature and energy density, nuclear matter undergoes a transition to a phase in which quarks and gluons are not confined: the Quark-Gluon Plasma (QGP) [1]. Such an extreme state of strongly-interacting QCD (Quantum Chromo-Dynamics) matter is produced in the laboratory with high-energy collisions of heavy nuclei, where an enhanced production of strange hadrons is observed [2-6]. Strangeness enhancement, originally proposed as a signature of QGP formation in nuclear collisions [7], is more pronounced for multi-strange baryons. Several effects typical of heavy-ion phenomenology have been observed in high-multiplicity proton-proton (pp) collisions [8,9]. Yet, enhanced production of multi-strange particles has not been reported so far. Here we present the first observation of strangeness enhancement in high-multiplicity pp collisions. We find that the integrated yields of strange and multi-strange particles relative to pions increases significantly with the event charged-particle multiplicity. The measurements are in remarkable agreement with p-Pb collision results [10,11] indicating that the phenomenon is related to the final system created in the collision. In high-multiplicity events strangeness production reaches values similar to those observed in Pb-Pb collisions, where a QGP is formed.

We present measurements of Underlying Event observables in pp collisions at $\sqrt{s}$ = 0.9 and 7 TeV. The analysis is performed as a function of the highest charged-particle transverse momentum $p_{\rm T, LT}$ in the event. Different regions are defined with respect to the azimuthal direction of the leading (highest transverse momentum) track: Toward, Transverse and Away. The Toward and Away regions collect the fragmentation products of the hardest partonic interaction. The Transverse region is expected to be most sensitive to the Underlying Event activity. The study is performed with charged particles above three different $p_{\rm T}$ thresholds: 0.15, 0.5 and 1.0 GeV/$c$. In the Transverse region we observe an increase in the multiplicity of a factor 2-3 between the lower and higher collision energies, depending on the track $p){\rm T}$ threshold considered. Data are compared to Pythia 6.4, Pythia 8.1 and Phojet. On average, all models considered underestimate the multiplicity and summed $p_{\rm T}$ in the Transverse region by about 10-30%.

The azimuthal correlations of D mesons and charged particles were measured with the ALICE detector in pp collisions at $\sqrt{s}=7$ TeV and p-Pb collisions at $\sqrt{s_{\rm NN}}=5.02$ TeV at the Large Hadron Collider. D$^0$, D$^+$, and D$^{*+}$ mesons and their charge conjugates with transverse momentum $3<p_{\rm T}<16$ GeV/$c$ and rapidity in the nucleon-nucleon centre-of-mass system $|y_{\rm cms}|<0.5$ (pp collisions) and $-0.96<y_{\rm cms}<0.04$ (p-Pb collisions) were correlated to charged particles with $p_{\rm T}>0.3$ Gev/$c$. The properties of the correlation peak induced by the jet containing the D meson, described in terms of the yield of charged particles in the peak and peak width, are compatible within uncertainties between the two collision systems, and described by Monte-Carlo simulations based on the PYTHIA, POWHEG and EPOS 3 event generators.

The correlations between event-by-event fluctuations of anisotropic flow harmonic amplitudes have been measured in Pb-Pb collisions at $\sqrt{s_{\rm NN}}$ = 2.76 TeV with the ALICE detector at the LHC. The results are reported in terms of multiparticle correlation observables dubbed Symmetric Cumulants. These observables are robust against biases originating from nonflow effects. The centrality dependence of correlations between the higher order harmonics (the quadrangular $v_4$ and pentagonal $v_5$ flow) and the lower order harmonics (the elliptic $v_2$ and triangular $v_3$ flow) is presented. The transverse momentum dependence of correlations between $v_3$ and $v_2$ and between $v_4$ and $v_2$ is also reported. The results are compared to calculations from viscous hydrodynamics and A Multi-Phase Transport ({AMPT}) model calculations. The comparisons to viscous hydrodynamic models demonstrate that the different order harmonic correlations respond differently to the initial conditions and the temperature dependence of the ratio of shear viscosity to entropy density ($\eta/s$). A small average value of $\eta/s$ is favored independent of the specific choice of initial conditions in the models. The calculations with the AMPT initial conditions yield results closest to the measurements. Correlations between the magnitudes of $v_2$, $v_3$ and $v_4$ show moderate $p_{\rm T}$ dependence in mid-central collisions. Together with existing measurements of individual flow harmonics, the presented results provide further constraints on the initial conditions and the transport properties of the system produced in heavy-ion collisions.

Measurements of anisotropic flow coefficients with two- and multi-particle cumulants for inclusive charged particles in Pb-Pb collisions at $\sqrt{{\textit s}_\text{NN}} = 5.02$ and 2.76 TeV are reported in the pseudorapidity range $|\eta| < 0.8$ and transverse momentum $0.2 < p_\text{T} < 50$ GeV/$c$. The full data sample collected by the ALICE detector in 2015 (2010), corresponding to an integrated luminosity of 12.7 (2.0) $\mu$b$^{-1}$ in the centrality range 0-80%, is analysed. Flow coefficients up to the sixth flow harmonic ($v_6$) are reported and a detailed comparison among results at the two energies is carried out. The $p_\text{T}$ dependence of anisotropic flow coefficients and its evolution with respect to centrality and harmonic number $n$ are investigated. An approximate power-law scaling of the form $v_n(p_\text{T}) \sim p_\text{T}^{n/3}$ is observed for all flow harmonics at low $p_\text{T}$ ($0.2 < p_\text{T} < 3$ GeV/$c$). At the same time, the ratios $v_n/v_m^{n/m}$ are observed to be essentially independent of $p_\text{T}$ for most centralities up to about $p_\text{T} = 10$ GeV/$c$. Analysing the differences among higher-order cumulants of elliptic flow ($v_2$), which have different sensitivities to flow fluctuations, a measurement of the standardised skewness of the event-by-event $v_2$ distribution $P(v_2)$ is reported and constraints on its higher moments are provided. The Elliptic Power distribution is used to parametrise $P(v_2)$, extracting its parameters from fits to cumulants. The measurements are compared to different model predictions in order to discriminate among initial-state models and to constrain the temperature dependence of the shear viscosity to entropy-density ratio.

We present the first azimuthally differential measurements of the pion source size relative to the second harmonic event plane in Pb-Pb collisions at a center-of-mass energy per nucleon-nucleon pair of $\sqrt{s_{\rm NN}}=2.76$ TeV. The measurements have been performed in the centrality range 0-50% and for pion pair transverse momenta $0.2 < k_{\rm T} < 0.7$ GeV/$c$. We find that the $R_{\rm side}$ and $R_{\rm out}$ radii, which characterize the pion source size in the directions perpendicular and parallel to the pion transverse momentum, oscillate out of phase, similar to what was observed at the Relativistic Heavy Ion Collider (RHIC). The final-state source eccentricity, estimated via $R_{\rm side}$ oscillations, is found to be significantly smaller than the initial-state source eccentricity, but remains positive; indicating that even after a stronger expansion in the in-plane direction, the pion source at the freeze-out is still elongated in the out-of-plane direction. The 3+1D hydrodynamic calculations are in qualitative agreement with observed centrality and transverse momentum $R_{\rm side}$ oscillations, but systematically underestimate the oscillation magnitude.

Comprehensive results on the production of unidentified charged particles, $\pi^{\pm}$, $\rm{K}^{\pm}$, $\rm{K}^{0}_{S}$, $\rm{K}$*(892)$^{0}$, $\rm{p}$, $\overline{\rm{p}}$, $\phi$(1020), $\Lambda$, $\overline{\Lambda}$, $\Xi^{-}$, $\overline{\Xi}^{+}$, $\Omega^{-}$ and $\overline{\Omega}^{+}$ hadrons in proton-proton (pp) collisions at $\sqrt{s}$ = 7 TeV at midrapidity ($|y| < 0.5$) as a function of charged-particle multiplicity density are presented. In order to avoid auto-correlation biases, the actual transverse momentum ($p_{\rm{T}}$) spectra of the particles under study and the event activity are measured in different rapidity windows. In the highest multiplicity class, the charged-particle density reaches about 3.5 times the value measured in inelastic collisions. While the yield of protons normalized to pions remains approximately constant as a function of multiplicity, the corresponding ratios of strange hadrons to pions show a significant enhancement that increases with increasing strangeness content. Furthermore, all identified particle to pion ratios are shown to depend solely on charged-particle multiplicity density, regardless of system type and collision energy. The evolution of the spectral shapes with multiplicity and hadron mass shows patterns that are similar to those observed in p-Pb and Pb-Pb collisions at LHC energies. The obtained $p_{\rm{T}}$ distributions and yields are compared to expectations from QCD-based pp event generators as well as to predictions from thermal and hydrodynamic models. These comparisons indicate that traces of a collective, equilibrated system are already present in high-multiplicity pp collisions.

The Quark Gluon Plasma (QGP) produced in ultra relativistic heavy-ion collisions at the Large Hadron Collider (LHC) can be studied by measuring the modifications of jets formed by hard scattered partons which interact with the medium. We studied these modifications via angular correlations of jets with charged hadrons for jets with momenta 20 < $p_{\rm{T}}^{\rm{jet}}$ < 40 GeV/$c$ as a function of the associated particle momentum. The reaction plane fit (RPF) method is used in this analysis to remove the flow modulated background. The analysis of angular correlations for different orientations of the jet relative to the second order event plane allows for the study of the path length dependence of medium modifications to jets. We present the dependence of azimuthal angular correlations of charged hadrons with respect to the angle of the axis of a reconstructed jet relative to the event plane in Pb-Pb collisions at $\sqrt{s_{\rm{NN}}}$ = 2.76 TeV. The dependence of particle yields associated with jets on the angle of the jet with respect to the event plane is presented. Correlations at different angles relative to the event plane are compared through ratios and differences of the yield. No dependence of the results on the angle of the jet with respect to the event plane is observed within uncertainties, which is consistent with no significant path length dependence of the medium modifications for this observable.

The transverse structure of jets was studied via jet fragmentation transverse momentum ($j_{\rm{T}}$) distributions, obtained using two-particle correlations in proton-proton and proton-lead collisions, measured with the ALICE experiment at the LHC. The highest transverse momentum particle in each event is used as the trigger particle and the region $3 < p_{\rm{Tt}} < 15$ GeV/$c$ is explored in this study. The measured distributions show a clear narrow Gaussian component and a wide non-Gaussian one. Based on Pythia simulations, the narrow component can be related to non-perturbative hadronization and the wide component to quantum chromodynamical splitting. The width of the narrow component shows a weak dependence on the transverse momentum of the trigger particle, in agreement with the expectation of universality of the hadronization process. On the other hand, the width of the wide component shows a rising trend suggesting increased branching for higher transverse momentum. The results obtained in pp collisions at $\sqrt{s}$ = 7 TeV and in p-Pb collisions at $\sqrt{s_{\rm{NN}}}$ = 5.02 TeV are compatible within uncertainties and hence no significant cold nuclear matter effects are observed. The results are compared to previous measurements from CCOR and PHENIX as well as to Pythia 8 and Herwig 7 simulations.

The production yield of prompt D mesons and their elliptic flow coefficient $v_2$ were measured with the Event-Shape Engineering (ESE) technique applied to mid-central (10-30% and 30-50% centrality classes) Pb-Pb collisions at the centre-of-mass energy per nucleon pair $\sqrt{s_{\rm NN}} =5.02$ TeV, with the ALICE detector at the LHC. The ESE technique allows the classification of events, belonging to the same centrality, according to the azimuthal anisotropy of soft particle production in the collision. The reported measurements give the opportunity to investigate the dynamics of charm quarks in the Quark-Gluon Plasma and provide information on their participation in the collective expansion of the medium. D mesons were reconstructed via their hadronic decays at mid-rapidity, $|\eta|<0.8$, in the transverse momentum interval $1<p_{\rm T}<24$ GeV/$c$. The $v_2$ coefficient is found to be sensitive to the event-shape selection confirming a correlation between the D-meson azimuthal anisotropy and the collective expansion of the bulk matter, while the per-event D-meson yields do not show any significant modification within the current uncertainties.

Azimuthally-differential femtoscopic measurements, being sensitive to spatio-temporal characteristics of the source as well as to the collective velocity fields at freeze out, provide very important information on the nature and dynamics of the system evolution. While the HBT radii oscillations relative to the second harmonic event plane measured recently reflect mostly the spatial geometry of the source, model studies have shown that the HBT radii oscillations relative to the third harmonic event plane are predominantly defined by the velocity fields. In this Letter, we present the first results on azimuthally-differential pion femtoscopy relative to the third harmonic event plane as a function of the pion pair transverse momentum $k_{\rm T}$ for different collision centralities in Pb-Pb collisions at $\sqrt{s_{\rm NN}}=2.76$ TeV. We find that the $R_{\rm side}$ and $R_{\rm out}$ radii, which characterize the pion source size in the directions perpendicular and parallel to the pion transverse momentum, oscillate in phase relative to the third harmonic event plane, similar to the results from 3+1D hydrodynamical calculations. The observed radii oscillations unambiguously signal a collective expansion and anisotropy in the velocity fields. A comparison of the measured radii oscillations with the Blast-Wave model calculations indicate that the initial state triangularity is washed-out at freeze out.

Charged-particle spectra at midrapidity are measured in Pb-Pb collisions at the centre-of-mass energy per nucleon-nucleon pair $\sqrt{s_{\rm NN}}$ = 5.02 TeV and presented in centrality classes ranging from most central (0-5%) to most peripheral (95-100%) collisions. Possible medium effects are quantified using the nuclear modification factor ($R_{\rm AA}$) by comparing the measured spectra with those from proton-proton collisions, scaled by the number of independent nucleon-nucleon collisions obtained from a Glauber model. At large transverse momenta ($8<p_{\rm T}<20$ GeV/$c$), the average $R_{\rm AA}$ is found to increase from about $0.15$ in 0-5% central to a maximum value of about $0.8$ in 75-85% peripheral collisions, beyond which it falls off strongly to below $0.2$ for the most peripheral collisions. Furthermore, $R_{\rm AA}$ initially exhibits a positive slope as a function of $p_{\rm T}$ in the $8$-$20$ GeV/$c$ interval, while for collisions beyond the 80% class the slope is negative. To reduce uncertainties related to event selection and normalization, we also provide the ratio of $R_{\rm AA}$ in adjacent centrality intervals. Our results in peripheral collisions are consistent with a PYTHIA-based model without nuclear modification, demonstrating that biases caused by the event selection and collision geometry can lead to the apparent suppression in peripheral collisions. This explains the unintuitive observation that $R_{\rm AA}$ is below unity in peripheral Pb-Pb, but equal to unity in minimum-bias p-Pb collisions despite similar charged-particle multiplicities.

The pseudorapidity density of charged particles, $\rm{d}\it{N}_\rm{ch}/\rm{d}\it{\eta}$, in p-Pb collisions has been measured at a centre-of-mass energy per nucleon-nucleon pair of $\sqrt{s_{\rm{NN}}}$ = 8.16 TeV at mid-pseudorapidity for non-single-diffractive events. The results cover 3.6 units of pseudorapidity, $|\eta|<1.8$. The $\rm{d}\it{N}_\rm{ch}/\rm{d}\it{\eta}$ value is $19.1\pm0.7$ at $|\eta|<0.5$. This quantity divided by $\langle N_\rm{part} \rangle/2$, is $4.73\pm0.20$, which is 9.5% higher than the corresponding value for p-Pb collisions at $\sqrt{s_{\rm{NN}}}$ = 5.02 TeV. Measurements are compared with models based on different mechanisms for particle production. All models agree within uncertainties with data in the Pb-going side, while HIJING overestimates, showing a symmetric behaviour, and EPOS underestimates the p-going side of the $\rm{d}\it{N}_\rm{ch}/\rm{d}\it{\eta}$ distribution. Saturation-based models reproduce the distributions well for $\eta>-1.3$. The $\rm{d}\it{N}_\rm{ch}/\rm{d}\it{\eta}$ is also measured for different centrality estimators, based both on the charged-particle multiplicity and on the energy deposited in the Zero-Degree Calorimeters. A study of the implications of the large multiplicity fluctuations due to the small number of participants for systems like p-Pb in the centrality calculation for multiplicity-based estimators is discussed, demonstrating the advantages of determining the centrality with energy deposited near beam rapidity.

Measurements of anisotropic flow coefficients ($v_n$) and their cross-correlations using two- and multi-particle cumulant methods are reported in collisions of pp at $\sqrt{s} = 13$ TeV, p-Pb at $\sqrt{s_{_{\rm NN}}} = 5.02$ TeV, Xe-Xe at $\sqrt{s_{_{\rm NN}}} = 5.44$ TeV, and Pb-Pb at $\sqrt{s_{_{\rm NN}}} = 5.02$ TeV recorded with the ALICE detector. The multiplicity dependence of $v_n$ is studied in a very wide range from 20 to 3000 particles produced in the mid-rapidity region $|\eta|<0.8$ for the transverse momentum range $0.2 < p_{\rm T} < 3.0$ GeV/$c$. An ordering of the coefficients $v_2 > v_3 > v_4$ is found in pp and p-Pb collisions, similar to that seen in large collision systems, while a weak $v_2$ multiplicity dependence is observed relative to nucleus-nucleus collisions in the same multiplicity range. Using a novel subevent method, $v_{2}$ measured with four-particle cumulants is found to be compatible with that from six-particle cumulants in pp and p-Pb collisions. The magnitude of the correlation between $v_n^2$ and $v_m^2$, evaluated with the symmetric cumulants SC$(m,n)$ is observed to be positive at all multiplicities for $v_2$ and $v_4$, while for $v_2$ and $v_3$ it is negative and changes sign for multiplicities below 100, which may indicate a different $v_n$ fluctuation pattern in this multiplicity range. The observed long-range multi-particle azimuthal correlations in high multiplicity pp and p-Pb collisions can neither be described by PYTHIA 8 nor by IP-Glasma+MUSIC+UrQMD model calculations, and hence provide new insights into the understanding of collective effects in small collision systems.

The measurement of the azimuthal-correlation function of prompt D mesons with charged particles in pp collisions at $\sqrt{s}$ = 5.02 TeV and p-Pb collisions at $\sqrt{s_{\rm NN}}$ = 5.02 TeV with the ALICE detector at the LHC is reported. The D$^{\rm 0}$, D$^{\rm +}$, and D$^{\rm *+}$ mesons, together with their charge conjugates, were reconstructed at midrapidity in the transverse momentum interval 3 < $p_{\rm T}$ < 24 GeV/c and correlated with charged particles having $p_{\rm T}$ > 0.3 GeV/c and pseudorapidity $|\eta| <$ 0.8. The properties of the correlation peaks appearing in the near- and away-side regions (for $\Delta \varphi \approx$ 0 and $\Delta \varphi \approx \pi$, respectively) were extracted via a fit to the azimuthal correlation functions. The shape of the correlation functions and the near- and away-side peak features are found to be consistent in pp and p-Pb collisions, showing no modifications due to nuclear effects within uncertainties. The results are compared with predictions from Monte Carlo simulations performed with the PYTHIA, POWHEG+PYTHIA, HERWIG, and EPOS 3 event generators.

Measurements of elliptic ($v_2$) and triangular ($v_3$) flow coefficients of $\pi^{\pm}$, K$^{\pm}$, p+$\rm \overline{p}$, K$^0_{\rm S}$, and $\Lambda + \overline{\Lambda}$ obtained with the scalar product method in Xe-Xe collisions at $\sqrt{s_{\rm NN}}$ = 5.44 TeV are presented. The results are obtained in the rapidity range $\left | y \right |<0.5$ and reported as a function of transverse momentum, $p_{\rm T}$, for several collision centrality classes. The flow coefficients exhibit a particle mass dependence for $p_{\rm T}<3$ GeV/$c$, while a grouping according to particle type (i.e., meson and baryon) is found at intermediate transverse momenta (3< $p_{\rm T}$ <8 GeV/$c$). The magnitude of the baryon $v_{2}$ is larger than that of mesons up to $p_{\rm T}$ = 6 GeV/$c$. The centrality dependence of the shape evolution of the $p_{\rm T}$-differential $v_2$ is studied for the various hadron species. The $v_2$ coefficients of $\pi^{\pm}$, K$^{\pm}$, and p+$\rm \overline{p}$ are reproduced by MUSIC hydrodynamic calculations coupled to a hadronic cascade model (UrQMD) for $p_{\rm T} <1$ GeV/$c$. A comparison with $v_{\rm n}$ measurements in the corresponding centrality intervals in Pb-Pb collisions at $\sqrt{s_{\rm NN}}$ = 5.02 TeV yields an enhanced $v_2$ in central collisions and diminished value in semicentral collisions.

The jet angularities are a class of jet substructure observables which characterize the angular and momentum distribution of particles within jets. These observables are sensitive to momentum scales ranging from perturbative hard scatterings to nonperturbative fragmentation into final-state hadrons. We report measurements of several groomed and ungroomed jet angularities in pp collisions at $\sqrt{s}=5.02$ TeV with the ALICE detector. Jets are reconstructed using charged particle tracks at midrapidity ($|\eta| < 0.9$). The anti-$k_{\rm T}$ algorithm is used with jet resolution parameters $R=0.2$ and $R=0.4$ for several transverse momentum $p_{\rm T}^{\text{ch jet}}$ intervals in the 20$-$100 GeV/$c$ range. Using the jet grooming algorithm Soft Drop, the sensitivity to softer, wide-angle processes, as well as the underlying event, can be reduced in a way which is well-controlled in theoretical calculations. We report the ungroomed jet angularities, $\lambda_{\alpha}$, and groomed jet angularities, $\lambda_{\alpha\text{,g}}$, to investigate the interplay between perturbative and nonperturbative effects at low jet momenta. Various angular exponent parameters $\alpha = 1$, 1.5, 2, and 3 are used to systematically vary the sensitivity of the observable to collinear and soft radiation. Results are compared to analytical predictions at next-to-leading-logarithmic accuracy, which provide a generally good description of the data in the perturbative regime but exhibit discrepancies in the nonperturbative regime. Moreover, these measurements serve as a baseline for future ones in heavy-ion collisions by providing new insight into the interplay between perturbative and nonperturbative effects in the angular and momentum substructure of jets. They supply crucial guidance on the selection of jet resolution parameter, jet transverse momentum, and angular scaling variable for jet quenching studies.

The production of $\mathrm{K}^{*}(\mathrm{892})^{0}$ and $\mathrm{\phi(1020)}$ resonances has been measured in p-Pb collisions at $\sqrt{s_{\rm NN}}$ = 8.16 TeV using the ALICE detector. Resonances are reconstructed via their hadronic decay channels in the rapidity interval $-$0.5 $<$$y$$<$ 0 and the transverse momentum spectra are measured for various multiplicity classes up to $p_{\rm T}$ = 20 GeV/$c$ for $\mathrm{K}^{*}(\mathrm{892})^{0}$ and $p_{\rm T}$ = 16 GeV/$c$ for $\mathrm{\phi(1020)}$. The $p_{\rm T}$ -integrated yields and mean transverse momenta are reported and compared with previous results in pp, p-Pb and Pb-Pb collisions. The $x_{\mathrm{T}}$ scaling for $\mathrm{K}^{*}(\mathrm{892})^{0}$ and $\mathrm{\phi(1020)}$ resonance production is newly tested in p-Pb collisions and found to hold in the high-$p_{\rm T}$ region at LHC energies. The nuclear modification factors ($R_{\rm pPb}$) as a function of $p_{\rm T}$ for $\mathrm{K}^{*0}$ and $\mathrm{\phi}$ at $\sqrt{s_{NN}}$ = 8.16 TeV are presented along with the new $R_{\rm pPb}$ measurements of $\mathrm{K}^{*0}$, $\mathrm{\phi}$ , $\Xi$, and $\Omega$ at $\sqrt{s_{\rm NN}}$ = 5.02 TeV. At intermediate $p_{\rm T}$ (2-8 GeV/$c$), $R_{\rm pPb}$ of $\Xi$, $\Omega$ show a Cronin-like enhancement, while $\mathrm{K}^{*0}$ and $\mathrm{\phi}$ show no or little nuclear modification. At high $p_{\rm T}$ ($>$ 8 GeV/$c$), the $R_{\rm pPb}$ values of all hadrons are consistent with unity within uncertainties. The $R_{\rm pPb}$ of $\mathrm{K}^{*}(\mathrm{892})^{0}$ and $\mathrm{\phi(1020)}$ at $\sqrt{s_{\rm NN}}$ = 8.16 and 5.02 TeV show no significant energy dependence.

This article reports measurements of the $p_{\rm{T}}$-differential inclusive jet cross-section in pp collisions at $\sqrt{s}$ = 5.02 TeV and the $p_{\rm{T}}$-differential inclusive jet yield in Pb-Pb 0-10% central collisions at $\sqrt{s_{\rm{NN}}}$ = 5.02 TeV. Jets were reconstructed at mid-rapidity with the ALICE tracking detectors and electromagnetic calorimeter using the anti-$k_{\rm{T}}$ algorithm. For pp collisions, we report jet cross-sections for jet resolution parameters $R=0.1-0.6$ over the range $20<p_{\rm{T,jet}}<140$ GeV/$c$, as well as the jet cross-section ratios of different $R$, and comparisons to two next-to-leading-order (NLO)-based theoretical predictions. For Pb-Pb collisions, we report the $R=0.2$ and $R=0.4$ jet spectra for $40<p_{\rm{T,jet}}<140$ GeV/$c$ and $60<p_{\rm{T,jet}}<140$ GeV/$c$, respectively. The scaled ratio of jet yields observed in Pb-Pb to pp collisions, $R_{\rm{AA}}$, is constructed, and exhibits strong jet quenching and a clear $p_{\rm{T}}$-dependence for $R=0.2$. No significant $R$-dependence of the jet $R_{\rm{AA}}$ is observed within the uncertainties of the measurement. These results are compared to several theoretical predictions.

The production of $\pi^{\pm}$, $\rm{K}^{\pm}$, $\rm{K}^{0}_{S}$, $\rm{K}^{*}(892)^{0}$, $\rm{p}$, $\phi(1020)$, $\Lambda$, $\Xi^{-}$, $\Omega^{-}$, and their antiparticles was measured in inelastic proton-proton (pp) collisions at a center-of-mass energy of $\sqrt{s}$ = 13 TeV at midrapidity ($|y|<0.5$) as a function of transverse momentum ($p_{\rm{T}}$) using the ALICE detector at the CERN LHC. Furthermore, the single-particle $p_{\rm{T}}$ distributions of $\rm{K}^{0}_{S}$, $\Lambda$, and $\overline{\Lambda}$ in inelastic pp collisions at $\sqrt{s}$ = 7 TeV are reported here for the first time. The $p_{\rm{T}}$ distributions are studied at midrapidity within the transverse momentum range $0\leq p_{\rm{T}}\leq20$ GeV/$c$, depending on the particle species. The $p_{\rm{T}}$ spectra, integrated yields, and particle yield ratios are discussed as a function of collision energy and compared with measurements at lower $\sqrt{s}$ and with results from various general-purpose QCD-inspired Monte Carlo models. A hardening of the spectra at high $p_{\rm{T}}$ with increasing collision energy is observed, which is similar for all particle species under study. The transverse mass and $x_{\rm{T}}\equiv2p_{\rm{T}}/\sqrt{s}$ scaling properties of hadron production are also studied. As the collision energy increases from $\sqrt{s}$ = 7 to 13 TeV, the yields of non- and single-strange hadrons normalized to the pion yields remain approximately constant as a function of $\sqrt{s}$, while ratios for multi-strange hadrons indicate enhancements. The $p_{\rm{T}}$-differential cross sections of $\pi^{\pm}$, $\rm{K}^{\pm}$ and $\rm{p}$ ($\overline{\rm{p}}$) are compared with next-to-leading order perturbative QCD calculations, which are found to overestimate the cross sections for $\pi^{\pm}$ and $\rm{p}$ ($\overline{\rm{p}}$) at high $p_{\rm{T}}$.

The production of K$^{*}(892)^{0}$ and $\phi(1020)$ mesons in proton-proton (pp) and lead-lead (Pb-Pb) collisions at $\sqrt{s_\mathrm{NN}} =$ 2.76 TeV has been analyzed using a high luminosity data sample accumulated in 2011 with the ALICE detector at the Large Hadron Collider (LHC). Transverse momentum ($p_{\mathrm{T}}$) spectra have been measured for K$^{*}(892)^{0}$ and $\phi(1020)$ mesons via their hadronic decay channels for $p_{\mathrm{T}}$ up to 20 GeV/$c$. The measurements in pp collisions have been compared to model calculations and used to determine the nuclear modification factor and particle ratios. The K$^{*}(892)^{0}$/K ratio exhibits significant reduction from pp to central Pb-Pb collisions, consistent with the suppression of the K$^{*}(892)^{0}$ yield at low $p_{\mathrm{T}}$ due to rescattering of its decay products in the hadronic phase. In central Pb-Pb collisions the $p_{\mathrm{T}}$ dependent $\phi(1020)/\pi$ and K$^{*}(892)^{0}$/$\pi$ ratios show an enhancement over pp collisions for $p_{\mathrm{T}}$ $\sim$3 GeV/$c$, consistent with previous observations of strong radial flow. At high $p_{\mathrm{T}}$, particle ratios in Pb-Pb collisions are similar to those measured in pp collisions. In central Pb-Pb collisions, the production of K$^{*}(892)^{0}$ and $\phi(1020)$ mesons is suppressed for $p_{\mathrm{T}}> 8$ GeV/$c$. This suppression is similar to that of charged pions, kaons and protons, indicating that the suppression does not depend on particle mass or flavor in the light quark sector.

The first measurements of elliptic flow of $\pi^\pm$, ${\rm K}^\pm$, p+$\overline{\rm p}$, ${\rm K_{S}^0}$, $\Lambda$+$\overline{\Lambda}$, $\phi$, $\Xi^-$+$\Xi^+$, and $\Omega^-$+$\Omega^+$ using multiparticle cumulants in Pb$-$Pb collisions at $\sqrt{s_{\rm NN}}$ = 5.02 TeV are presented. Results obtained with two- ($v_2\{2\}$) and four-particle cumulants ($v_2\{4\}$) are shown as a function of transverse momentum, $p_{\rm T}$, for various collision centrality intervals. Combining the data for both $v_2\{2\}$ and $v_2\{4\}$ also allows us to report the first measurements of the mean elliptic flow, elliptic flow fluctuations, and relative elliptic flow fluctuations for various hadron species. These observables probe the event-by-event eccentricity fluctuations in the initial state and the contributions from the dynamic evolution of the expanding quark-gluon plasma. The characteristic features observed in previous $p_{\rm T}$-differential anisotropic flow measurements for identified hadrons with two-particle correlations, namely the mass ordering at low $p_{\rm T}$ and the approximate scaling with the number of constituent quarks at intermediate $p_{\rm T}$, are similarly present in the four-particle correlations and the combinations of $v_2\{2\}$ and $v_2\{4\}$. In addition, a particle species dependence of flow fluctuations is observed that could indicate a significant contribution from final state hadronic interactions. The comparison between experimental measurements and CoLBT model calculations, which combine the various physics processes of hydrodynamics, quark coalescence, and jet fragmentation, illustrates their importance over a wide $p_{\rm T}$ range.

The production of K$^{*}(892)^{0}$ and $\phi(1020)$ mesons in proton-proton (pp) and lead-lead (Pb-Pb) collisions at $\sqrt{s_\mathrm{NN}} = 5.02$ TeV has been measured using the ALICE detector at the Large Hadron Collider (LHC). The transverse momentum ($p_{\mathrm{T}}$) distributions of K$^{*}(892)^{0}$ and $\phi(1020)$ mesons have been measured at midrapidity $(|y|<0.5)$ up to $p_{\mathrm{T}} = 20$ GeV$/c$ in inelastic pp collisions and for several Pb-Pb collision centralities. The collision centrality and collision energy dependence of the average transverse momenta agree with the radial flow scenario observed with stable hadrons, showing that the effect is stronger for more central collisions and higher collision energies. The $\mathrm{K^{*0}/K}$ ratio is found to be suppressed in Pb-Pb collisions relative to pp collisions: this indicates a loss of the measured K$^{*}(892)^{0}$ signal due to rescattering of its decay products in the hadronic phase. In contrast, for the longer-lived $\phi(1020)$ mesons, no such suppression is observed. The nuclear modification factors ($R_{\rm AA}$) of K$^{*}(892)^{0}$ and $\phi(1020)$ mesons are calculated using pp reference spectra at the same collision energy. In central Pb-Pb collisions for $p_{\rm T} > 8$ GeV$/c$, the $R_{\rm AA}$ values of K$^{*}(892)^{0}$ and $\phi(1020)$ are below unity and observed to be similar to those of pions, kaons, and (anti)protons. The $R_{\rm AA}$ values at high $p_{\mathrm T}$ ($>$~8 GeV$/c$) for K$^{*}(892)^{0}$ and $\phi(1020)$ mesons are in agreement within uncertainties for $\sqrt{s_\mathrm{NN}} = 5.02$ and 2.76 TeV.

The transverse-momentum ($p_{\rm T}$) spectra of ${\rm K}^*(892)^0$ and $\phi(1020)$ measured with the ALICE detector up to $p_{\rm T}$ = 16 GeV/$c$ in the rapidity range $-1.2 < y < 0.3$, in p-Pb collisions at the center-of-mass energy per nucleon-nucleon collision $\sqrt{s_{\rm NN}}$ = 5.02 TeV are presented as a function of charged particle multiplicity and rapidity. The measured $p_{\rm T}$ distributions show a dependence on both multiplicity and rapidity at low $p_{\rm T}$ whereas no significant dependence is observed at high $p_{\rm T}$. A rapidity dependence is observed in the $p_{\rm T}$-integrated yield (d$N$/d$y$), whereas the mean transverse momentum ($\left< p_{\rm T} \right>$) shows a flat behavior as a function of rapidity. The rapidity asymmetry ($Y_{\rm asym}$) at low $p_{\rm T}$ ( < 5 GeV/$c$) is more significant for higher multiplicity classes. At high $p_{\rm T}$, no significant rapidity asymmetry is observed in any of the multiplicity classes. Both ${\rm K}^*(892)^0$ and $\phi(1020)$ show similar $Y_{\rm asym}$. The nuclear modification factor ($Q_{\rm CP}$) as a function of $p_{\rm T}$ shows a Cronin-like enhancement at intermediate $p_{\rm T}$, which is more prominent at higher rapidities (Pb-going direction) and in higher multiplicity classes. At high $p_{\rm T}$ (> 5 GeV/$c$), the $Q_{\rm CP}$ values are greater than unity and no significant rapidity dependence is observed.

The first evidence of spin alignment of vector mesons ($K^{*0}$ and $\phi$) in heavy-ion collisions at the Large Hadron Collider (LHC) is reported. The spin density matrix element $\rho_{00}$ is measured at midrapidity ($|y| <$ 0.5) in Pb-Pb collisions at a center-of-mass energy ($\sqrt{s_{\rm NN}}$) of 2.76 TeV with the ALICE detector. $\rho_{00}$ values are found to be less than 1/3 (1/3 implies no spin alignment) at low transverse momentum ($p_{\rm T} <$ 2 GeV/$c$) for $K^{*0}$ and $\phi$ at a level of 3$\sigma$ and 2$\sigma$, respectively. No significant spin alignment is observed for the $K^0_S$ meson (spin = 0) in Pb-Pb collisions and for the vector mesons in $pp$ collisions. The measured spin alignment is unexpectedly large but qualitatively consistent with the expectation from models which attribute it to a polarization of quarks in the presence of angular momentum in heavy-ion collisions and a subsequent hadronization by the process of recombination.

The first measurement of the production of pions, kaons, (anti-)protons and $\phi$ mesons at midrapidity in Xe-Xe collisions at $\sqrt{s_{\rm NN}} = 5.44$ TeV is presented. Transverse momentum ($p_{\rm T}$) spectra and $p_{\rm T}$-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 study of Xe-Xe and Pb-Pb collisions allows systems at similar charged-particle multiplicities but with different initial geometrical eccentricities to be investigated. A detailed comparison of the spectral shapes in the two systems reveals an opposite behaviour for radial and elliptic flow. In particular, this study shows that the radial flow does not depend on the colliding system when compared at similar charged-particle multiplicity. In terms of hadron chemistry, the previously observed smooth evolution of particle ratios with multiplicity from small to large collision systems is also found to hold in Xe-Xe. In addition, our results confirm that two remarkable features of particle production at LHC energies are also valid in the collision of medium-sized nuclei: the lower proton-to-pion ratio with respect to the thermal model expectations and the increase of the $\phi$-to-pion ratio with increasing final-state multiplicity.

The inclusive production of the J/$\psi$ and $\psi$(2S) charmonium states is studied as a function of centrality in p-Pb collisions at a centre-of-mass energy per nucleon pair $\sqrt{s_{\rm NN}} = 8.16$ TeV at the LHC. The measurement is performed in the dimuon decay channel with the ALICE apparatus in the centre-of-mass rapidity intervals $-4.46 < y_{\rm cms} < -2.96$ (Pb-going direction) and $2.03 < y_{\rm cms} < 3.53$ (p-going direction), down to zero transverse momentum ($p_{\rm T}$). The J/$\psi$ and $\psi$(2S) production cross sections are evaluated as a function of the collision centrality, estimated through the energy deposited in the zero degree calorimeter located in the Pb-going direction. The $p_{\rm T}$-differential J/$\psi$ production cross section is measured at backward and forward rapidity for several centrality classes, together with the corresponding average $\langle p_{\rm T} \rangle$ and $\langle p^{2}_{\rm T} \rangle$ values. The nuclear effects affecting the production of both charmonium states are studied using the nuclear modification factor. In the p-going direction, a suppression of the production of both charmonium states is observed, which seems to increase from peripheral to central collisions. In the Pb-going direction, however, the centrality dependence is different for the two states: the nuclear modification factor of the J/$\psi$ increases from below unity in peripheral collisions to above unity in central collisions, while for the $\psi$(2S) it stays below or consistent with unity for all centralities with no significant centrality dependence. The results are compared with measurements in p-Pb collisions at $\sqrt{s_{\rm NN}} = 5.02$ TeV and no significant dependence on the energy of the collision is observed. Finally, the results are compared with theoretical models implementing various nuclear matter effects.

The elliptic ($v_2$), triangular ($v_3$), and quadrangular ($v_4$) flow coefficients of $\pi^{\pm}$, ${\rm K}^{\pm}$, ${\rm p+\overline{p}}$, ${\Lambda+\overline{\Lambda}}$, ${\rm K}^{\rm 0}_{\rm S}$, and the $\phi$-meson are measured in Pb-Pb collisions at $\sqrt{s_{\rm NN}}=5.02$ TeV. Results obtained with the scalar product method are reported for the rapidity range $\vert y \vert <$ 0.5 as a function of transverse momentum, $p_\text{T}$, at different collision centrality intervals between 0-70%, including ultra-central (0-1%) collisions for $\pi^{\pm}$, ${\rm K}^{\pm}$, and ${\rm p+\overline{p}}$. For $p_\text{T} < 3$ GeV$\kern-0.05em/\kern-0.02em c$, the flow coefficients exhibit a particle mass dependence. At intermediate transverse momenta ($3<p_\text{T}<$~8-10 GeV$\kern-0.05em/\kern-0.02em c$), particles show an approximate grouping according to their type (i.e., mesons and baryons). The $\phi$-meson $v_2$, which tests both particle mass dependence and type scaling, follows ${\rm p+\overline{p}}$ $v_2$ at low $p_\text{T}$ and $\pi^{\pm}$ $v_2$ at intermediate $p_\text{T}$. The evolution of the shape of $v_{\rm n}(p_{\mathrm{T}})$ as a function of centrality and harmonic number $n$ is studied for the various particle species. Flow coefficients of $\pi^{\pm}$, ${\rm K}^{\pm}$, and ${\rm p+\overline{p}}$ for $p_\text{T}<3$ GeV$\kern-0.05em/\kern-0.02em c$ are compared to iEBE-VISHNU and MUSIC hydrodynamical calculations coupled to a hadronic cascade model (UrQMD). The iEBE-VISHNU calculations describe the results fairly well for $p_\text{T} < 2.5$ GeV$\kern-0.05em/\kern-0.02em c$, while MUSIC calculations reproduce the measurements for $p_\text{T} < 1$ GeV$\kern-0.05em/\kern-0.02em c$. A comparison to $v_{\rm n}$ coefficients measured in Pb-Pb collisions at $\sqrt{s_{\rm NN}}$ = 2.76 TeV is also provided.

The measurement of azimuthal correlations of charged particles is presented for Pb-Pb collisions at $\sqrt{s_{\rm NN}}=$ 2.76 TeV and p-Pb collisions at $\sqrt{s_{\rm NN}}=$ 5.02 TeV with the ALICE detector at the CERN Large Hadron Collider. These correlations are measured for the second, third and fourth order flow vector in the pseudorapidity region $|\eta|<0.8$ as a function of centrality and transverse momentum $p_{\rm T}$ using two observables, to search for evidence of $p_{\rm T}$-dependent flow vector fluctuations. For Pb-Pb collisions at 2.76 TeV, the measurements indicate that $p_{\rm T}$-dependent fluctuations are only present for the second order flow vector. Similar results have been found for p-Pb collisions at 5.02 TeV. These measurements are compared to hydrodynamic model calculations with event-by-event geometry fluctuations in the initial state to constrain the initial conditions and transport properties of the matter created in Pb-Pb and p-Pb collisions.

In ultrarelativistic heavy-ion collisions, the event-by-event variation of the elliptic flow $v_2$ reflects fluctuations in the shape of the initial state of the system. This allows to select events with the same centrality but different initial geometry. This selection technique, Event Shape Engineering, has been used in the analysis of charge-dependent two- and three-particle correlations in Pb-Pb collisions at $\sqrt{s_{_{\rm NN}}} =2.76$ TeV. The two-particle correlator $\langle \cos(\varphi_\alpha - \varphi_\beta) \rangle$, calculated for different combinations of charges $\alpha$ and $\beta$, is almost independent of $v_2$ (for a given centrality), while the three-particle correlator $\langle \cos(\varphi_\alpha + \varphi_\beta - 2\Psi_2) \rangle$ scales almost linearly both with the event $v_2$ and charged-particle pseudorapidity density. The charge dependence of the three-particle correlator is often interpreted as evidence for the Chiral Magnetic Effect (CME), a parity violating effect of the strong interaction. However, its measured dependence on $v_2$ points to a large non-CME contribution to the correlator. Comparing the results with Monte Carlo calculations including a magnetic field due to the spectators, the upper limit of the CME signal contribution to the three-particle correlator in the 10-50% centrality interval is found to be 26-33% at 95% confidence level.

Angular correlations of heavy-flavour and charged particles in high-energy proton-proton collisions are sensitive to the production mechanisms of heavy quarks and to their fragmentation as well as hadronisation processes. The measurement of the azimuthal-correlation function of prompt D mesons with charged particles in proton-proton collisions at a centre-of-mass energy of $\sqrt{s} = 13$ TeV with the ALICE detector is reported, considering D$^{0}$, D$^{+}$, and D$^{*+}$ mesons in the transverse-momentum interval $3 < p_{\rm T} < 36$ GeV/$c$ at midrapidity ($|y| < 0.5$), and charged particles with $p_{\rm T} > 0.3$ GeV/$c$ and pseudorapidity $|\eta| < 0.8$. This measurement has an improved precision and provides an extended transverse-momentum coverage compared to previous ALICE measurements at lower energies. The study is also performed as a function of the charged-particle multiplicity, showing no modifications of the correlation function with multiplicity within uncertainties. The properties and the transverse-momentum evolution of the near- and away-side correlation peaks are studied and compared with predictions from various Monte Carlo event generators. Among those considered, PYTHIA8 and POWHEG+PYTHIA8 provide the best description of the measured observables. The obtained results can provide guidance on tuning the generators.

This paper presents the measurements of $\pi^{\pm}$, $\rm{K}^{\pm}$, $\rm{p}$ and $\bar{\rm{p}}$ transverse momentum ($p_{\rm{T}}$) spectra as a function of charged-particle multiplicity density in proton-proton (pp) collisions at $\sqrt{s}$ = 13 TeV with the ALICE detector at the LHC. Such study allows us to isolate the center-of-mass energy dependence of light-flavour particle production. The measurements reported here cover a $p_{\rm{T}}$ range from 0.1 GeV/$c$ to 20 GeV/$c$ and are done in the rapidity interval $|y|<0.5$. The $p_{\rm{T}}$-differential particle ratios exhibit an evolution with multiplicity, similar to that observed in pp collisions at $\sqrt{s}$ = 7 TeV, which is qualitatively described by some of the hydrodynamical and pQCD-inspired models discussed in this paper. Furthermore, the $p_{\rm{T}}$-integrated hadron-to-pion yield ratios measured in pp collisions at two different center-of-mass energies are consistent when compared at similar multiplicities. This also extends to strange and multistrange hadrons, suggesting that, at LHC energies, particle hadrochemistry scales with particle multiplicity the same way under different collision energies and colliding systems.

Measurements of identified hadrons as a function of the charged-particle multiplicity in pp collisions enable a search for the onset of collective effects in small collision systems. With such measurements, it is possible to study the mechanisms that determine the shapes of hadron transverse momentum ($p_{\rm{T}}$) spectra, to search for possible modifications of the yields of short-lived hadronic resonances due to scattering effects in the hadron-gas phase, and to investigate different explanations for the multiplicity evolution of strangeness production provided by phenomenological models. In this paper, these topics are addressed through measurements of the $\rm{K}^{*}(892)^{0}$ and $\phi(1020)$ mesons at midrapidity in pp collisions at $\sqrt{s}$ = 13 TeV as a function of the charged-particle multiplicity. The results include the $p_{\rm{T}}$ spectra, $p_{\rm{T}}$-integrated yields, mean transverse momenta, and the ratios of the yields of these resonances to those of longer-lived hadrons. Comparisons with results from other collision systems and energies, as well as predictions from phenomenological models, are also discussed.

The inclusive J/$\psi$ production in Pb-Pb collisions at the center-of-mass energy per nucleon pair $\sqrt{s_{\rm{NN}}}$ = 5.02 TeV, measured with the ALICE detector at the CERN LHC, is reported. The J/$\psi$ meson is reconstructed via the dimuon decay channel at forward rapidity ($2.5<y<4$) down to zero transverse momentum. The suppression of the J/$\psi$ yield in Pb-Pb collisions with respect to binary-scaled pp collisions is quantified by the nuclear modification factor ($R_{\rm{AA}}$). The $R_{\rm{AA}}$ at $\sqrt{s_{\rm{NN}}}$ = 5.02 TeV is presented and compared with previous measurements at $\sqrt{s_{\rm{NN}}}$ = 2.76 TeV as a function of the centrality of the collision, and of the J/$\psi$ transverse momentum and rapidity. The inclusive J/$\psi$ $R_{\rm{AA}}$ shows a suppression increasing toward higher $p_{\rm{T}}$, with a steeper dependence for central collisions. The modification of the J/$\psi$ average $p_{\rm{T}}$ and $p_{\rm{T}}^{2}$ is also studied. Comparisons with the results of models based on a transport equation and on statistical hadronization are also carried out.

The measurement of the deuteron and anti-deuteron production in the rapidity range $-1 < y < 0$ as a function of transverse momentum and event multiplicity in p-Pb collisions at $\sqrt{s_{\rm{NN}}}$ = 5.02 TeV is presented. (Anti-)deuterons are identified via their specific energy loss $\rm{d}E/\rm{d}x$ and via their time-of-flight. Their production in p-Pb collisions is compared to pp and Pb-Pb collisions and is discussed within the context of thermal and coalescence models. The ratio of integrated yields of deuterons to protons (d/p) shows a significant increase as a function of the charged-particle multiplicity of the event starting from values similar to those observed in pp collisions at low multiplicities and approaching those observed in Pb-Pb collisions at high multiplicities. The mean transverse momenta are extracted from the deuteron spectra and the values are similar to those obtained for p and $\Lambda$ particles. Thus, deuteron spectra do not follow mass ordering. This behaviour is in contrast to the trend observed for non-composite particles in p-Pb collisions. In addition, the production of the rare $^{3}{\rm{He}}$ and $^{3}\bar{\rm He}$ nuclei has been studied. The spectrum corresponding to all non-single diffractive p-Pb collisions is obtained in the rapidity window $-1 < y < 0$ and the $p_{\rm{T}}$-integrated yield d$N$/d$y$ is extracted. It is found that the yields of protons, deuterons, and $^{3}{\rm{He}}$, normalised by the spin degeneracy factor, follow an exponential decrease with mass number.

We report measurements of the production of prompt D$^0$, D$^+$, D$^{*+}$ and D$^+_{\rm s}$ mesons in Pb-Pb collisions at the centre-of-mass energy per nucleon-nucleon pair $\sqrt{s_{\rm NN}}=5.02$ TeV, in the centrality classes 0-10%, 30-50% and 60-80%. The D-meson production yields are measured at mid-rapidity ($|y|<0.5$) as a function of transverse momentum ($p_{\rm T}$). The $p_{\rm T}$ intervals covered in central collisions are: $1<p_{\rm T}<50$ Gev/$c$ for D$^0$, $2<p_{\rm T}<50$ GeV/$c$ for D$^+$, $3<p_{\rm T}<50$ GeV/$c$ for D$^{*+}$, and $4<p_{\rm T}<16$ GeV/$c$ for D$^+_{\rm s}$ mesons. The nuclear modification factors ($R_{\rm AA}$) for non-strange D mesons (D$^0$, D$^+$, D$^{*+}$) show minimum values of about 0.2 for $p_{\rm T}$ = 6-10 GeV/$c$ in the most central collisions and are compatible within uncertainties with those measured at $\sqrt{s_{\rm NN}}=2.76$ TeV. For D$^+_{\rm s}$ mesons, the values of $R_{\rm AA}$ are larger than those of non-strange D mesons, but compatible within uncertainties. In central collisions the average $R_{\rm AA}$ of non-strange D mesons is compatible with that of charged particles for $p_{\rm T} > 8$ GeV/$c$, while it is larger at lower $p_{\rm T}$. The nuclear modification factors for strange and non-strange D mesons are also compared to theoretical models with different implementations of in-medium energy loss.