A Large Ion Collider Experiment

Off

LS2 installation: TPC

Off

ITS Outer Barrel

Off

LS2 Installations: ITS Outer Barrel and MFT

Off

LS2 Installation: FIT

Off

Heavy-ion collision

Off

proton-proton collision

Off

ALICE INDICO

update on - 03:55:14

ALICE Calendar

< February >

M	T	W	T	F	S	S
26	27	28	29	30	31	1
2	3	4	5	6	7	8
9	10	11	12	13	14	15
16	17	18	19	20	21	22
23	24	25	26	27	28	1

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

CERN/ALICE-CIAE Joint Lab launched

On 28 January, the inaugural meeting of the CERN/ALICE - China Institute of Atomic Energy (CIAE) Joint Lab was held in Beijing Science and Technology Park. ....: Read more

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

Latest ALICE Submissions

Observation of flow vector fluctuations in p$-$Pb collisions at $\mathbf{\sqrt{\textit{s}_{_{\bf NN}}}}=$ 5.02 TeVMeasurements of transverse momentum ($p_{\rm T}$) and pseudorapidity ($η$) dependent flow vector fluctuations in p$-$Pb collisions at $\sqrt{s_{_{\rm NN}}} = 5.02$ TeV at the CERN Large Hadron Collider are presented. By studying long-range two-particle correlations with a template fit method, potential biases from non-flow effects such as jets and resonance decays are effectively suppressed. Significant $p_{\rm T}$- and $η$-dependent fluctuations of the second-harmonic flow vector are observed with more than 5$σ$ confidence in p$-$Pb collisions, similar to the observations in Pb$-$Pb collisions. The influence of residual non-flow effects has been evaluated and cannot account for the observed fluctuations, thereby confirming the observation of flow vector fluctuations in small collision systems at the LHC. Comparisons to model calculations from 3DGlauber+MUSIC+UrQMD and the parton transport model from AMPT are also presented. The measurements provide constraints on the theoretical modelling of the three-dimensional initial geometry and its event-by-event fluctuations, offering critical insights into the origin of collective flow in small collision systems at the LHC.	2602.10645
Inclusive and multiplicity-dependent pseudorapidity densities of charged particles in pp collisions at $\mathbf{\sqrt{s} = 13.6}$ TeVThe distribution of the pseudorapidity density of primary charged particles (${\rm d}N_{\rm ch}/ {\rm d}η$) in $\|η\| < ~1.5$ is measured in pp collisions at a center-of-mass energy of 13.6 TeV using the ALICE detector. Tracks are reconstructed with the upgraded Inner Tracking System and Time Projection Chamber, and results are reported for the INEL$>$0 event class (events having at least one charged particle in $\|η\| < ~1$). The multiplicity dependence of the pseudorapidity density of charged particles is also explored with the multiplicity determined by the forward detectors. The average charged-particle pseudorapidity density at midrapidity ($\|η\| < ~0.5$) is measured to be $\langle \mathrm{d}N_{\mathrm{ch}}/\mathrm{d}η\rangle = 7.10 \pm 0.18$. Combined with lower-energy measurements, the INEL$>$0 results follow a power-law scaling with the center-of-mass energy. These measurements provide a new reference for charged-particle production at the highest proton$-$proton collision energy available at the LHC.	2602.10658
Space-time evolution of particle emission in p$-$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
Strangeness production as a function of charged-particle multiplicity in proton-proton collisions at ${\bf \sqrt{s}~=~5.02}$ TeV(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 LHC, using proton-proton collisions at a center-of-mass energy of ${\bf \sqrt{s}~=~5.02}$~TeV. This study extends similar studies performed at ${\bf \sqrt{s}~=~7}$~TeV and ${\bf \sqrt{s}~=~13}$~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 those 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 to 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.	2511.10306

See all submissions...

Upcoming Conferences (Next Week)

See all conferences...

Jobs info

ALICE Job - Postdoctoral Position – ALICE Finnish Team (FoCal & Jet Analysis) (12-02-2026 )

ALICE Job - Postdoctoral position in high-energy nuclear physics at the University of California, Berkeley (10-02-2026 )

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.