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ALICE INDICO

update on - 16:31:10

ALICE Calendar

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ALICE is optimized to study the collisions of nuclei at the ultra-relativistic energies provided by the LHC. The aim is to study the physics of strongly interacting matter at the highest energy densities reached so far in the laboratory. In such conditions, an extreme phase of matter - called the quark-gluon plasma - is formed. Our universe is thought to have been in such a primordial state for the first few millionths of a second after the Big Bang, before quarks and gluons were bound together to form protons and neutrons. Recreating this primordial state of matter in the laboratory and understanding how it evolves will allow us to shed light on questions about how matter is organized and the mechanisms that confine quarks and gluons. For this purpose, we are carrying out a comprehensive study of the hadrons, electrons, muons, and photons produced in the collisions of heavy nuclei (²⁰⁸Pb). ALICE is also studying proton-proton and proton-nucleus collisions both as a comparison with nucleus-nucleus collisions and in their own right. In 2021, ALICE completed a significant upgrade of its detectors to further enhance its capabilities and continue its scientific journey at the LHC in Run 3 and 4, until the end of 2032. At the same time, upgrade plans are being made for ALICE 3, the next-generation experiment for LHC Runs 5 and 6.

Recent highlights

Strangeness at its extremes

Strangeness production in high-energy hadron collisions is a powerful tool ....: Read more

ALICE welcomes its new management

ALICE enters 2026 with a newly appointed management team, led by Kai Schweda as Spokesperson, succeeding Marco van Leeuwen: Read more

Season's greetings and Happy New Year

Best wishes for the holidays and Happy New Year 2026: Read more

Latest ALICE Submissions

Space-time evolution of particle emission in p$-$Pb collisions at $\mathbf{\sqrt{s_{\rm NN}}=~5.02}$ TeV with 3D kaon femtoscopyThe measurement of three-dimensional femtoscopic correlations between identical charged kaons (K$^\pm$K$^\pm$) produced in p$-$Pb collisions at center-of-mass energy per nucleon pair $\sqrt{s{_{\rm NN}}} = 5.02$ TeV with ALICE at the LHC is presented for the first time. This measurement, supplementary to those in pp and Pb$-$Pb collisions, allows understanding the particle-production mechanisms at different charged-particle multiplicities and provides information on the dynamics of the source of particles created in p$-$Pb collisions, for which a general consensus does not yet exist. It is shown that the measured source sizes increase with charged-particle multiplicity and decrease with increasing pair transverse momentum. These trends for K$^\pm$K$^\pm$ are similar to the ones observed earlier in identical charged-pion and K$_{\rm s}^{0}$K$_{\rm s}^{0}$ correlations in Pb$-$Pb collisions at various energies and in $π^\pm π^\pm$ correlations in p$-$Pb collisions at $\sqrt{s{_{\rm NN}}} = 5.02$ TeV. At comparable multiplicity, the source sizes measured in p$-$Pb collisions agree within uncertainties with those observed in pp collisions, and there is an indication that they are smaller than those observed in Pb$-$Pb collisions. The obtained results are also compared with predictions from the hadronic interaction model EPOS~3, which tends to underestimate the source size for the most central collisions and agrees with the data for semicentral and peripheral events. Furthermore, the time of maximal emission for kaons is extracted. It turns out to be comparable with the value obtained in highly peripheral Pb$-$Pb collisions at the same energy, indicating that the kaon emission evolution is similar to that in p$-$Pb collisions.	2601.15081
One- and three-dimensional identical charged-kaon femtoscopic correlations in Pb--Pb collisions at $\mathbf{ \sqrt{s_\mathrm{NN}}=5.02}$ TeVThe identical charged-kaon correlations induced by quantum-statistics effects and final-state interactions are measured in Pb$-$Pb collisions at $\sqrt{s_{\rm NN}} = 5.02$ TeV. The results of one- (1D) and three-dimensional (3D) analyses show that the obtained system-size parameters (radii) are smaller for more peripheral collisions and decrease with increasing pair transverse momentum $k_{\rm T}$. The 1D parameters agree within uncertainties with those obtained in Pb$-$Pb collisions at $\sqrt{s_{\rm NN}}=2.76$ TeV. The observed power-law dependence of the extracted 3D radii as a function of the pair transverse momentum is a signature of the collective flow in the particle-emitting system created in Pb$-$Pb collisions. This dependence is well reproduced by the integrated hydrokinetic model calculations except for the outward projection of the radius (measured in the longitudinally co-moving system) for the most central collisions. The time of maximal emission for kaons is extracted from the 3D analysis in a wide collision centrality range from 0 to 90%. Its reduction with decreasing charged-particle multiplicity is well reproduced by the hydrokinetic model predictions, and means that kaons are emitted earlier in more peripheral events.	2601.15054
Time resolution of the ALICE Time-Of-Flight detector with the first Run 3 pp collisions at ${\bf \sqrt{\textit{s}} = 13.6}$ TeVParticle identification (PID) is a fundamental aspect of the ALICE detector system, central to its heavy-ion and proton-proton physics programs. Among the different PID strategies, ALICE uses the Time-Of-Flight (TOF) detector to identify particles at intermediate momenta ($0.5 < ~ p_{\rm T} < ~ 4$ GeV/$c$). The ALICE TOF detector performed successfully during the first ten years of LHC operations. During the Long Shutdown 2, many ALICE sub-detectors, including TOF, were upgraded to fully leverage the targeted 50 kHz interaction rate of Pb-Pb collisions, which required the implementation of a continuous readout scheme. The TOF detector electronics were upgraded and refurbished, while processing algorithms for data quality control, reconstruction, calibration, and analysis were rewritten. This paper presents the upgraded TOF detector operation and calibration procedures and its performance in terms of timing resolution, a key factor for particle separation in ALICE analyses. Using 2022 pp collision data at $\sqrt{s} = 13.6$ TeV from Run 3, the time resolution of the detector was estimated with two independent methods, both yielding consistent results, better than 80 ps. Despite the excellent performance already achieved, further improvements are expected after additional detector commissioning and refined calibration procedures, thus enhancing the ALICE PID capabilities for Run 3 and beyond.	2511.10311
Multiplicity dependence of two-particle angular correlations of identified particles in pp collisions at $\mathbf{\sqrt{s} = 13}$ TeVTwo-particle angular correlations explore particle production mechanisms and underlying event-wide phenomena present in the systems created in hadronic collisions. These correlations are examined as a function of rapidity and azimuthal-angle differences ($Δy, Δ\varphi$) for pairs of like- and unlike-sign pions, kaons, and (anti-)protons produced in pp collisions at $\sqrt{s}$ = 13 TeV, measured by the ALICE experiment. Two-particle correlation functions are provided, along with $Δy$ and $Δ\varphi$ projections, and are compared to Monte Carlo (MC) model predictions. For the first time, the measurement is performed as a function of the event's charged-particle density. The shapes of the correlation functions are studied in detail for each particle pair. Previous studies conducted for pp collisions at $\sqrt{s}$ = 7 TeV at ALICE have revealed an anticorrelation at small relative angles for baryon-baryon and antibaryon-antibaryon pairs, whose origin remains an open question. In this work, an additional approach is introduced to study the multiplicity dependence of the correlation functions in more detail and reveal qualitative differences in the underlying sources of correlations, such as quantum statistics, final-state interactions, and resonance decays. The puzzling near-side anticorrelation in baryon-baryon measurements is observed across all multiplicity classes and remains a challenge for models of particle production in pp collisions. Furthermore, the multiplicity dependence of the correlations between mesons provides an independent means to explore the sensitivity of current MC models to soft-QCD effects and hadronization dynamics. The presented measurements, together with the baryon results, enrich the experimental picture of two-particle correlations in pp collisions and serve as valuable input for ongoing theoretical developments.	2511.10399
Centrality dependence of strange particle production in Pb-Pb collisions at $\sqrt{s_{\rm NN}} = 5.02$ TeVThe centrality dependence of strange ($K_S^0$, $Λ+ \barΛ$) and multi-strange ($Ξ^- + \bar{Ξ^+}$, $Ω^- + \barΩ^+$) hadron production is measured by ALICE in the LHC lead-lead (Pb-Pb) collisions at a center-of-mass energy per nucleon pair $\sqrt{s_{\rm NN}} = 5.02$~TeV, using the full data set collected during the LHC Run 2 campaign in the years 2015 and 2018. This is the largest heavy-ion data set 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 ($\langle dN_{ch}/dη\rangle_{\|η\| < ~0.5}$), probing regions where smaller collision system (pp and p-Pb) results are also available. The $p_T$ spectra evolve with centrality, featuring higher $\langle p_T \rangle$ 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 $\langle dN_{ch}/dη\rangle_{\|η\| < ~0.5}$ and compared to results from different collision systems and energies. A smooth connection from pp 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 pp 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.	2511.10360

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Upcoming Conferences (Next Week)

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Diversity and Inclusivity in ALICE

The ALICE Collaboration embraces and values the diversity of its team members and colleagues. We are committed to fostering an inclusive environment for all people regardless of their nationality/culture, profession, age/generation, family situation and gender, as well as individual differences such as but not limited to ethnic origin, sexual orientation, belief, disability, or opinions provided that they are consistent with the Organization’s values.