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Item type:Publication, Measurement of the transverse-momentum fraction of strange hadrons from jet-like correlation structures in pp collisions at s=13 TeV(Elsevier B.V., 2026-09-01)The first measurements of the average transverse-momentum fraction (⟨ z ⟩) as a function of transverse momentum (p T) for strange baryons (Λ and Λ‾) and strange mesons (KS0), produced in mini-jets defined through angular correlations in pp collisions at s=13 TeV, are reported by the ALICE Collaboration at the LHC. The observable is obtained using a novel method, where the angular correlation between the strange hadrons and inclusive charged hadrons is weighted by the p T of correlated particles at small angular distance. As a function of strange particles’ p T, the results reveal a flat trend for strange mesons and a decreasing trend for strange baryons in the measured p T region, indicating distinct hadronization mechanisms for KS0 and Λ (Λ‾). The measurements are compared to Monte Carlo models, namely Pythia 8 (with both Monash and Color Rope tunes) and the AMPT (A Multi-Phase Transport) model with string melting. None of these models provides a satisfactory description of the ⟨ z ⟩ distributions at low and intermediate p T. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Limits on the chiral magnetic effect from the event shape engineering and participant-spectator correlation techniques in Pb–Pb collisions at sNN=5.02 TeV(Elsevier B.V., 2026-09-01)The latest experimental studies related to the search for the Chiral Magnetic Effect (CME) in Pb–Pb collisions at sNN=5.02 TeV recorded with the ALICE detector at the Large Hadron Collider (LHC) are presented. Charge-dependent two-particle correlations relative to the reaction plane are measured for charged particles in the pseudorapidity range | η | < 0.8 and the transverse-momentum range 0.2 < p T < 5 GeV/ c . Two approaches have been employed: in the first method, the contribution of the background to the measurement is varied using the event shape engineering (ESE), while the second relies on changing the contribution of the potential CME signal by measuring azimuthal correlations relative to the participant plane, where the background contributions are maximized, and spectator plane, where the CME signal contribution is maximized. Both methods yield results consistent with the absence of a CME signal within the measurement uncertainties. The result obtained from correlations relative to different symmetry planes, a technique applied for the first time at LHC energies, gives the possibility to test independently and confirm the upper limits from previous measurements, while the new limit from the ESE analysis offers improved constraint relative to previous attempts. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Exposing the parton-hadron transition within jets with energy-energy correlators in pp collisions at s = 5.02 TeV(American Physical Society, 2026-06-12)This paper presents a fully corrected measurement of the energy-energy correlator (EEC) within jets in pp collisions. The EEC traces the energy flow as a highly energetic parton undergoes a QCD shower followed by the confinement of partons into hadrons, probing the correlation function of the energy flow inside jets. The EEC observable is measured as a function of the charged particle pair angular distance, R L , for 20 < p T ch jet < 80 GeV / c . In the perturbative region (large R L ), a good agreement between the data and a next-to-leading-log perturbative QCD calculation is observed. In the nonperturbative region (small R L ), the data exhibit a linear R L dependence. There is a transition region in between, characterized by a turnover in the EEC distribution, indicating where hadronization effects begin to dominate. The peak of this transition region is located at 2.43 ± 0.14 GeV / c / ⟨ p T ch jet ⟩ for jets of various energies, indicating a common energy scale for the hadronization process. State-of-the-art Monte Carlo event generators are compared with the measurements, and can be used to constrain the parton shower and hadronization mechanisms. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Measurement of π 0 -hadron correlations relative to the event plane in semicentral Pb-Pb collisions at s N N = 5.02 TeV(American Physical Society, 2026-06-04)Per-trigger yields of π 0 − hadron correlations were measured in semicentral Pb-Pb collisions at s NN = 5.02 TeV in ALICE at the CERN Large Hadron Collider. The reconstructed π 0 → γ γ , with a transverse momentum of 11 GeV / c < p T ( π 0 ) < 14 GeV / c , is used as the trigger particle to calculate yields of associated charged particles on the near- and away-side. The photons are reconstructed using the ALICE Electromagnetic Calorimeter, and the charged particles are measured in the ALICE central barrel within a pseudorapidity range of | η | < 0.8 . The yields are reported relative to the orientation of the π 0 with the second-order event plane and are background subtracted using the reaction-plane fit method. The data give an indication of a suppression of the associated charged-particle yields near p T ≈ 2 GeV / c when comparing out-of-plane to in-plane trigger particles. At associated charged-particle p T > 3 GeV/ c , no significant event-plane dependence is observed within uncertainties. The results are compared with predictions from the JEWEL model, which implements jet energy loss in an expanding medium. JEWEL predicts no significant modification of either the near- or away-side associated yields, independent of whether medium recoils are included. The observed behavior may indicate the presence of additional energy-loss mechanisms beyond those governed by path-length dependence. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Strangeness production as a function of charged-particle multiplicity in proton-proton collisions at s = 5.02 TeV(American Physical Society, 2026-05-21)(Multi-)strange particle production rates and transverse momentum distributions are measured at midrapidity ( | y | < 0.5 ) as a function of the charged-particle multiplicity density by the ALICE experiment at the CERN Large Hadron Collider (LHC), using proton-proton collisions at a center-of-mass energy of s = 5.02 TeV. This study extends similar studies performed at s = 7 TeV and s = 13 TeV to a lower-energy regime, improving the statistical precision and extending the measurement to previously unexplored low-multiplicity regions. While K S 0 , Λ , and Ξ yields can be described with a linear multiplicity dependence within uncertainties, the Ω yields follow a significantly faster than linear increasing trend. For all analyzed particles, the overall production rate is consistent with that observed at higher energy and at similar multiplicity densities. Transverse momentum distributions are observed to evolve with multiplicity. Several state-of-the-art QCD-inspired Monte Carlo models have been compared with the data, testing some recently introduced features to address the findings at higher energies. Models can qualitatively describe the transverse momentum spectra and the Λ / K S 0 spectral ratio only if collectivity is introduced in the evolution of the system.1 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Centrality dependence of strange particle production in Pb-Pb collisions at s N N = 5.02 TeV(American Physical Society, 2026-05-26)The centrality dependence of strange ( K S 0 , Λ + Λ ¯ ) and multistrange ( Ξ − + Ξ ¯ + , Ω − + Ω ¯ + ) hadron production is measured by ALICE in the Large Hadron Collider (LHC) lead-lead (Pb-Pb) collisions at a center-of-mass energy per nucleon pair s N N = 5.02 TeV, using the full dataset collected during the LHC Run 2 campaign in the years 2015 and 2018. This is the largest heavy-ion dataset analyzed to date at the LHC, and it allows for the extraction of transverse momentum ( p T ) spectra and p T -integrated yields with unprecedented precision, over a broad range of charged particle multiplicity densities ( 〈 d N ch / d η 〉 | η | < 0.5 ), probing regions where smaller collision system ( and p -Pb) results are also available. The p T spectra evolve with centrality, featuring higher 〈 p T 〉 in central events for all particles. The Λ / K S 0 ratio exhibits the distinctive baryon-to-meson enhancement in the intermediate p T region, with a maximum which is shifted to larger p T for more central collisions. The hadron-to-pion yield ratios are presented as a function of 〈 d N ch / d η 〉 | η | < 0.5 and compared to results from different collision systems and energies. A smooth connection from to Pb-Pb is observed, thus demonstrating that collision system or energy do not play a role in the multiplicity evolution of this observable. The previously reported enhancement of strangeness production in the multiplicity range probed in and p -Pb collisions saturates in the multiplicity range of Pb-Pb data. These results constitute a key test bench for theoretical models and a first comparison to the EPOS 4 generator is presented.1 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Evidence for J/ψ Suppression in Incoherent Photonuclear Production(American Physical Society, 2026-07-31)According to quantum chromodynamics, at sufficiently high energy, the structure of hadrons reveals a dynamic equilibrium between gluon splitting and gluon recombination - a phenomenon known as saturation. The process of diffractive photonuclear production of a J/ψ vector meson provides a direct insight into the gluon composition of hadrons. The J/ψ production as a function of momentum transferred in the interaction, quantified by the Mandelstam-t variable, serves as an excellent probe for studying the structure of hadrons within the impact-parameter plane, because different ranges in t are sensitive to the dynamics of the gluon field at varying spatial size scales. The ALICE Collaboration has measured the energy dependence of incoherent photonuclear production of J/ψ mesons off lead ions, at sNN=5.02 TeV, for three Mandelstam-t intervals. The energy dependence of the photonuclear cross section at the highest |t| range measured, (0.81<|t|<1.44) GeV2, is sensitive to subnucleonic structures of the Pb target. The increase of the cross section with energy at large |t| shows evidence of suppression with respect to the increase seen at low |t|. The observed pattern of the energy evolution in data is similar to that of gluon saturation models. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Evidence of Nuclear Geometry-Driven Anisotropic Flow in O + O and Ne + Ne Collisions at s NN = 5.36 TeV(American Physical Society, 2026-05-15)A central question in strong-interaction physics, governed by quantum chromodynamics (QCD), is whether femtoscale droplets of quark-gluon plasma form in small collision systems involving projectiles significantly smaller than heavy ions. Collisions of light ions such as O 16 and Ne 20 offer a unique opportunity to probe the emergence of collective behavior in QCD matter. This Letter presents the first measurements of the elliptic ( v 2 ) and triangular ( v 3 ) flow of charged particles in O 16 – O 16 and Ne 20 – Ne 20 collisions at a center-of-mass energy per nucleon pair of s NN = 5.36 TeV with the ALICE detector. The hydrodynamic model predictions, explicitly incorporating the nuclear structures of O 16 and Ne 20 , exhibit a good agreement with the flow measurements presented. The observed increase of v 2 in central Ne–Ne collisions relative to OO collisions, driven by the nuclear geometries, highlights the importance of utilizing light nuclei with well-defined geometric shapes to constrain the initial conditions. These findings support the presence of nuclear geometry-driven hydrodynamic flow in light-ion collisions at the LHC.1 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, ?+ production in pp collisions at s=13 TeV(Springer Science+Business Media, 2026-02-01)The measurement of $$\Sigma ^{+}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msup> <mml:mi>?</mml:mi> <mml:mo>+</mml:mo> </mml:msup> </mml:math> production in pp collisions at $$\sqrt{s}=13$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:msqrt> <mml:mi>s</mml:mi> </mml:msqrt> <mml:mo>=</mml:mo> <mml:mn>13</mml:mn> </mml:mrow> </mml:math> TeV is presented. The measurement is performed at midrapidity in both minimum-bias and high-multiplicity pp collisions at $$\sqrt{s} =13$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:msqrt> <mml:mi>s</mml:mi> </mml:msqrt> <mml:mo>=</mml:mo> <mml:mn>13</mml:mn> </mml:mrow> </mml:math> TeV. The $$\Sigma ^{+}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msup> <mml:mi>?</mml:mi> <mml:mo>+</mml:mo> </mml:msup> </mml:math> is reconstructed via its weak-decay topology in the decay channel $$\Sigma ^{+} \rightarrow \mathrm{{p}} + \pi ^{0}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:msup> <mml:mi>?</mml:mi> <mml:mo>+</mml:mo> </mml:msup> <mml:mo>?</mml:mo> <mml:mi>p</mml:mi> <mml:mo>+</mml:mo> <mml:msup> <mml:mi>?</mml:mi> <mml:mn>0</mml:mn> </mml:msup> </mml:mrow> </mml:math> with $$\pi ^{0} \rightarrow \gamma + \gamma .$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:msup> <mml:mi>?</mml:mi> <mml:mn>0</mml:mn> </mml:msup> <mml:mo>?</mml:mo> <mml:mi>?</mml:mi> <mml:mo>+</mml:mo> <mml:mi>?</mml:mi> <mml:mo>.</mml:mo> </mml:mrow> </mml:math> In a novel approach, the neutral pion is reconstructed by combining photons that convert in the detector material with photons measured in the calorimeters. The transverse-momentum $$(p_{\textrm{T}})$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mo>(</mml:mo> <mml:msub> <mml:mi>p</mml:mi> <mml:mtext>T</mml:mtext> </mml:msub> <mml:mo>)</mml:mo> </mml:mrow> </mml:math> distributions of the $$\Sigma ^{+}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msup> <mml:mi>?</mml:mi> <mml:mo>+</mml:mo> </mml:msup> </mml:math> and its rapidity densities $${\textrm{d}}N$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mtext>d</mml:mtext> <mml:mi>N</mml:mi> </mml:mrow> </mml:math> / $${\textrm{d}}y$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mtext>d</mml:mtext> <mml:mi>y</mml:mi> </mml:mrow> </mml:math> in both event classes are reported. The $$p_{\textrm{T}}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mi>p</mml:mi> <mml:mtext>T</mml:mtext> </mml:msub> </mml:math> spectrum in minimum-bias collisions is compared to QCD-inspired event generators. The ratio of $$\Sigma ^{+}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msup> <mml:mi>?</mml:mi> <mml:mo>+</mml:mo> </mml:msup> </mml:math> to previously measured $$\Lambda $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>?</mml:mi> </mml:math> baryons is in good agreement with calculations from the Statistical Hadronization Model. The high efficiency and purity of the novel reconstruction method for $$\Sigma ^{+}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msup> <mml:mi>?</mml:mi> <mml:mo>+</mml:mo> </mml:msup> </mml:math> presented here will enable future studies of the interaction of $$\Sigma ^{+}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML">8 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Σ¯± production in pp and p-Pb collisions at sNN=5.02 TeV with ALICE(Springer Science+Business Media, 2026-02-01)The transverse momentum spectra and integrated yields of anti- $$\Sigma $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>Σ</mml:mi> </mml:math> hyperons ( $$\overline{\Sigma }^{\pm } $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msup> <mml:mover> <mml:mi>Σ</mml:mi> <mml:mo>¯</mml:mo> </mml:mover> <mml:mo>±</mml:mo> </mml:msup> </mml:math> ) have been measured in $$\text {pp}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mtext>pp</mml:mtext> </mml:math> and $$\text {p}{-}\text {Pb}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mtext>p</mml:mtext> <mml:mo>-</mml:mo> <mml:mtext>Pb</mml:mtext> </mml:mrow> </mml:math> collisions at $$\sqrt{s_{\textrm{NN}}}=5.02$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:msqrt> <mml:msub> <mml:mi>s</mml:mi> <mml:mtext>NN</mml:mtext> </mml:msub> </mml:msqrt> <mml:mo>=</mml:mo> <mml:mn>5.02</mml:mn> </mml:mrow> </mml:math> TeV with the ALICE experiment. Measurements are performed via the newly accessed decay channel $$\overline{\Sigma }^{\pm } \!\!\rightarrow \mathrm{\overline{n}} \pi ^{\pm }$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:msup> <mml:mover> <mml:mi>Σ</mml:mi> <mml:mo>¯</mml:mo> </mml:mover> <mml:mo>±</mml:mo> </mml:msup> <mml:mspace/> <mml:mspace/> <mml:mo>→</mml:mo> <mml:mover> <mml:mi>n</mml:mi> <mml:mo>¯</mml:mo> </mml:mover> <mml:msup> <mml:mi>π</mml:mi> <mml:mo>±</mml:mo> </mml:msup> </mml:mrow> </mml:math> . A new method of antineutron reconstruction with the PHOS electromagnetic spectrometer is developed and applied to this analysis. The $$p_{\textrm{T}}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mi>p</mml:mi> <mml:mtext>T</mml:mtext> </mml:msub> </mml:math> spectra of $$\overline{\Sigma }^{\pm } $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msup> <mml:mover> <mml:mi>Σ</mml:mi> <mml:mo>¯</mml:mo> </mml:mover> <mml:mo>±</mml:mo> </mml:msup> </mml:math> are measured in the range $$0.5<p_{\textrm{T}} <3$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mn>0.5</mml:mn> <mml:mo><</mml:mo> <mml:msub> <mml:mi>p</mml:mi> <mml:mtext>T</mml:mtext> </mml:msub> <mml:mo><</mml:mo> <mml:mn>3</mml:mn> </mml:mrow> </mml:math> GeV/ $$c$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>c</mml:mi> </mml:math> and compared to predictions of the PYTHIA 8, DPMJET, PHOJET, EPOS LHC and EPOS4 models. The EPOS LHC and EPOS4 models provide the best descriptions of the measured spectra both in $$\text {pp}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mtext>pp</mml:mtext> </mml:math> and $$\text {p}{-}\text {Pb}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mtext>p</mml:mtext> <mml:mo>-</mml:mo> <mml:mtext>Pb</mml:mtext> </mml:mrow> </mml:math> collisions, while models which do not account for multiparton interactions provide a considerably worse description at high $$p_{\textrm{T}}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mi>p</mml:mi> <mml:mtext>T</mml:mtext> </mml:msub> </mml:math> . The total yields of $$\overline{\Sigma }^{\pm } $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msup> <mml:mover> <mml:mi>Σ</mml:mi> <mml:mo>¯</mml:mo> </mml:mover> <mml:mo>±</mml:mo> </mml:msup> </mml:math> in both9