The differential invariant yield as a function of transverse momentum (<math><msub><mrow><mi>p</mi></mrow><mrow><mi>T</mi></mrow></msub></math>) of electrons from semileptonic heavy-flavour hadron decays was measured at midrapidity in central (0–10%), semi-central (30–50%) and peripheral (60–80%) lead–lead (Pb–Pb) collisions at <math><msqrt><mrow><msub><mrow><mi>s</mi></mrow><mrow><mi>NN</mi></mrow></msub></mrow></msqrt><mo>=</mo><mn>5.02</mn><mtext> TeV</mtext></math> in the <math><msub><mrow><mi>p</mi></mrow><mrow><mi>T</mi></mrow></msub></math> intervals 0.5–26 GeV/c (0–10% and 30–50%) and 0.5–10 GeV/c (60–80%). The production cross section in proton–proton (pp) collisions at <math><msqrt><mrow><mi>s</mi></mrow></msqrt><mo>=</mo><mn>5.02</mn></math> TeV was measured as well in <math><mn>0.5</mn><mo>&lt;</mo><msub><mrow><mi>p</mi></mrow><mrow><mi>T</mi></mrow></msub><mo>&lt;</mo><mn>10</mn></math> GeV/c and it lies close to the upper band of perturbative QCD calculation uncertainties up to <math><msub><mrow><mi>p</mi></mrow><mrow><mi>T</mi></mrow></msub><mo>=</mo><mn>5</mn></math> GeV/c and close to the mean value for larger <math><msub><mrow><mi>p</mi></mrow><mrow><mi>T</mi></mrow></msub></math>. The modification of the electron yield with respect to what is expected for an incoherent superposition of nucleon–nucleon collisions is evaluated by measuring the nuclear modification factor <math><msub><mrow><mi>R</mi></mrow><mrow><mi>AA</mi></mrow></msub></math>. The measurement of the <math><msub><mrow><mi>R</mi></mrow><mrow><mi>AA</mi></mrow></msub></math> in different centrality classes allows in-medium energy loss of charm and beauty quarks to be investigated. The <math><msub><mrow><mi>R</mi></mrow><mrow><mi>AA</mi></mrow></msub></math> shows a suppression with respect to unity at intermediate <math><msub><mrow><mi>p</mi></mrow><mrow><mi>T</mi></mrow></msub></math>, which increases while moving towards more central collisions. Moreover, the measured <math><msub><mrow><mi>R</mi></mrow><mrow><mi>AA</mi></mrow></msub></math> is sensitive to the modification of the parton distribution functions (PDF) in nuclei, like nuclear shadowing, which causes a suppression of the heavy-quark production at low <math><msub><mrow><mi>p</mi></mrow><mrow><mi>T</mi></mrow></msub></math> in heavy-ion collisions at LHC.

India

S. Acharya

Czechia

D. Adamová

S.P. Adhya

Germany

A. Adler

Sweden

J. Adolfsson

M.M. Aggarwal

CERN

G. Aglieri Rinella

Italy

M. Agnello

N. Agrawal

Z. Ahammed

S. Ahmad

South Korea

S.U. Ahn

Russia

A. Akindinov

M. Al-Turany

S.N. Alam

Brazil

D.S.D. Albuquerque

D. Aleksandrov

B. Alessandro

China

H.M. Alfanda

Mexico

R. Alfaro Molina

B. Ali

Pakistan

Y. Ali

A. Alici

Ukraine

A. Alkin

Norway

J. Alme

T. Alt

L. Altenkamper

I. Altsybeev

M.N. Anaam

Romania

C. Andrei

D. Andreou

United Kingdom

H.A. Andrews

A. Andronic

M. Angeletti

V. Anguelov

United States

C. Anson

Croatia

T. Antičić

F. Antinori

P. Antonioli

R. Anwar

N. Apadula

France

L. Aphecetche

H. Appelshäuser

S. Arcelli

R. Arnaldi

M. Arratia

I.C. Arsene

M. Arslandok

A. Augustinus

R. Averbeck

S. Aziz

M.D. Azmi

A. Badalà

Y.W. Baek

S. Bagnasco

X. Bai

R. Bailhache

R. Bala

A. Baldisseri

M. Ball

S. Balouza

R.C. Baral

R. Barbera

L. Barioglio

Hungary

G.G. Barnaföldi

L.S. Barnby

V. Barret

P. Bartalini

K. Barth

E. Bartsch

F. Baruffaldi

N. Bastid

S. Basu

G. Batigne

JINR

B. Batyunya

P.C. Batzing

D. Bauri

Peru

J.L. Bazo Alba

Denmark

I.G. Bearden

Netherlands

C. Bedda

N.K. Behera

I. Belikov

F. Bellini

R. Bellwied

V. Belyaev

G. Bencedi

S. Beole

A. Bercuci

Y. Berdnikov

D. Berenyi

R.A. Bertens

D. Berzano

M.G. Besoiu

L. Betev

A. Bhasin

I.R. Bhat

M.A. Bhat

H. Bhatt

B. Bhattacharjee

A. Bianchi

Measurement of electrons from semileptonic heavy-flavour hadron decays at midrapidity in pp and Pb–Pb collisions at TeV

The elliptic flow (<math><msub><mrow><mi>v</mi></mrow><mrow><mn>2</mn></mrow></msub></math>) of (anti-)$^{3}$He is measured in Pb–Pb collisions at <math><msqrt><mrow><msub><mrow><mi>s</mi></mrow><mrow><mi>NN</mi></mrow></msub></mrow></msqrt><mo>=</mo><mn>5.02</mn><mspace width="0.25em"></mspace><mtext>TeV</mtext></math> in the transverse-momentum (<math><msub><mrow><mi>p</mi></mrow><mrow><mi>T</mi></mrow></msub></math>) range of 2–6 GeV/c for the centrality classes 0–20%, 20–40%, and 40–60% using the event-plane method. This measurement is compared to that of pions, kaons, and protons at the same center-of-mass energy. A clear mass ordering is observed at low <math><msub><mrow><mi>p</mi></mrow><mrow><mi>T</mi></mrow></msub></math>, as expected from relativistic hydrodynamics. The violation of the scaling of <math><msub><mrow><mi>v</mi></mrow><mrow><mn>2</mn></mrow></msub></math> with the number of constituent quarks at low <math><msub><mrow><mi>p</mi></mrow><mrow><mi>T</mi></mrow></msub></math>, already observed for identified hadrons and deuterons at LHC energies, is confirmed also for (anti-)$^{3}$He. The elliptic flow of (anti-)$^{3}$He is underestimated by the Blast-Wave model and overestimated by a simple coalescence approach based on nucleon scaling. The elliptic flow of (anti-)$^{3}$He measured in the centrality classes 0–20% and 20–40% is well described by a more sophisticated coalescence model where the phase-space distributions of protons and neutrons are generated using the iEBE-VISHNU hybrid model with AMPT initial conditions.

Measurement of the (anti-) He elliptic flow in Pb–Pb collisions at

The ALICE collaboration at the CERN LHC reports novel measurements of jet substructure in pp collisions at <math><msqrt><mrow><mi>s</mi></mrow></msqrt><mspace width="0.25em"></mspace><mo>=</mo><mn>7</mn></math> TeV and central Pb–Pb collisions at <math><msub><mrow><msqrt><mrow><mi>s</mi></mrow></msqrt></mrow><mrow><mi>NN</mi></mrow></msub><mspace width="0.25em"></mspace><mo>=</mo><mn>2.76</mn></math> TeV. Jet substructure of track-based jets is explored via iterative declustering and grooming techniques. We present the measurement of the momentum sharing of two-prong substructure exposed via grooming, the <math><msub><mrow><mi>z</mi></mrow><mrow><mi>g</mi></mrow></msub></math>, and its dependence on the opening angle, in both pp and Pb–Pb collisions. We also present the measurement of the distribution of the number of branches obtained in the iterative declustering of the jet, which is interpreted as the number of its hard splittings. In Pb–Pb collisions, we observe a suppression of symmetric splittings at large opening angles and an enhancement of splittings at small opening angles relative to pp collisions, with no significant modification of the number of splittings. The results are compared to predictions from various Monte Carlo event generators to test the role of important concepts in the evolution of the jet in the medium such as colour coherence.

L. Bianchi

Exploration of jet substructure using iterative declustering in pp and Pb–Pb collisions at LHC energies

Two-particle correlation functions were measured for <math><mi>p</mi><mover><mrow><mi>p</mi></mrow><mo>‾</mo></mover></math>, <math><mi>p</mi><mover><mrow><mi>Λ</mi></mrow><mo>‾</mo></mover></math>, <math><mover><mrow><mi>p</mi></mrow><mo>‾</mo></mover><mi>Λ</mi></math>, and <math><mi>Λ</mi><mover><mrow><mi>Λ</mi></mrow><mo>‾</mo></mover></math> pairs in Pb–Pb collisions at <math><msqrt><mrow><msub><mrow><mi>s</mi></mrow><mrow><mi>NN</mi></mrow></msub></mrow></msqrt><mo>=</mo><mn>2.76</mn></math> TeV and <math><msqrt><mrow><msub><mrow><mi>s</mi></mrow><mrow><mi>NN</mi></mrow></msub></mrow></msqrt><mo>=</mo><mn>5.02</mn></math> TeV recorded by the ALICE detector. From a simultaneous fit to all obtained correlation functions, real and imaginary components of the scattering lengths, as well as the effective ranges, were extracted for combined <math><mi>p</mi><mover><mrow><mi>Λ</mi></mrow><mo>‾</mo></mover></math> and <math><mover><mrow><mi>p</mi></mrow><mo>‾</mo></mover><mi>Λ</mi></math> pairs and, for the first time, for <math><mi>Λ</mi><mover><mrow><mi>Λ</mi></mrow><mo>‾</mo></mover></math> pairs. Effective averaged scattering parameters for heavier baryon–antibaryon pairs, not measured directly, are also provided. The results reveal similarly strong interaction between measured baryon–antibaryon pairs, suggesting that they all annihilate in the same manner at the same pair relative momentum <math><msup><mrow><mi>k</mi></mrow><mrow><mo>⁎</mo></mrow></msup></math>. Moreover, the reported significant non-zero imaginary part and negative real part of the scattering length provide motivation for future baryon–antibaryon bound state searches.

S. Aiola

L.G.E. Beltran

N. Bianchi

J. Bielčík

Measurement of strange baryon–antibaryon interactions with femtoscopic correlations

A measurement of the production of prompt <math><msubsup><mrow><mi>Λ</mi></mrow><mrow><mi>c</mi></mrow><mrow><mo>+</mo></mrow></msubsup></math> baryons in Pb–Pb collisions at <math><msqrt><mrow><msub><mrow><mi>s</mi></mrow><mrow><mi>NN</mi></mrow></msub></mrow></msqrt><mo>=</mo><mn>5.02</mn></math> TeV with the ALICE detector at the LHC is reported. The <math><msubsup><mrow><mi>Λ</mi></mrow><mrow><mi>c</mi></mrow><mrow><mo>+</mo></mrow></msubsup></math> and <math><msup><mrow><msub><mrow><mover><mrow><mi>Λ</mi></mrow><mo>‾</mo></mover></mrow><mrow><mi>c</mi></mrow></msub></mrow><mrow><mo>−</mo></mrow></msup></math> were reconstructed at midrapidity (<math><mo>|</mo><mi>y</mi><mo>|</mo><mo>&lt;</mo><mn>0.5</mn></math>) via the hadronic decay channel <math><msubsup><mrow><mi>Λ</mi></mrow><mrow><mi>c</mi></mrow><mrow><mo>+</mo></mrow></msubsup><mo>→</mo><mi>p</mi><msubsup><mrow><mi>K</mi></mrow><mrow><mi>S</mi></mrow><mrow><mn>0</mn></mrow></msubsup></math> (and charge conjugate) in the transverse momentum and centrality intervals <math><mn>6</mn><mo>&lt;</mo><msub><mrow><mi>p</mi></mrow><mrow><mi>T</mi></mrow></msub><mo>&lt;</mo><mn>12</mn></math> GeV/c and 0–80%. The <math><msubsup><mrow><mi>Λ</mi></mrow><mrow><mi>c</mi></mrow><mrow><mo>+</mo></mrow></msubsup><mo>/</mo><msup><mrow><mi>D</mi></mrow><mrow><mn>0</mn></mrow></msup></math> ratio, which is sensitive to the charm quark hadronisation mechanisms in the medium, is measured and found to be larger than the ratio measured in minimum-bias pp collisions at <math><msqrt><mrow><mi>s</mi></mrow></msqrt><mo>=</mo><mn>7</mn></math> TeV and in p–Pb collisions at <math><msqrt><mrow><msub><mrow><mi>s</mi></mrow><mrow><mi>NN</mi></mrow></msub></mrow></msqrt><mo>=</mo><mn>5.02</mn></math> TeV. In particular, the values in p–Pb and Pb–Pb collisions differ by about two standard deviations of the combined statistical and systematic uncertainties in the common <math><msub><mrow><mi>p</mi></mrow><mrow><mi>T</mi></mrow></msub></math> interval covered by the measurements in the two collision systems. The <math><msup><mrow><msub><mrow><mi>Λ</mi></mrow><mrow><mi>c</mi></mrow></msub></mrow><mrow><mo>+</mo></mrow></msup><mo>/</mo><msup><mrow><mi>D</mi></mrow><mrow><mn>0</mn></mrow></msup></math> ratio is also compared with model calculations including different implementations of charm quark hadronisation. The measured ratio is reproduced by models implementing a pure coalescence scenario, while adding a fragmentation contribution leads to an underestimation. The <math><msubsup><mrow><mi>Λ</mi></mrow><mrow><mi>c</mi></mrow><mrow><mo>+</mo></mrow></msubsup></math> nuclear modification factor, <math><msub><mrow><mi>R</mi></mrow><mrow><mi>AA</mi></mrow></msub></math>, is also presented. The measured values of the <math><msub><mrow><mi>R</mi></mrow><mrow><mi>AA</mi></mrow></msub></math> of <math><msubsup><mrow><mi>Λ</mi></mrow><mrow><mi>c</mi></mrow><mrow><mo>+</mo></mrow></msubsup></math>, <math><msubsup><mrow><mi>D</mi></mrow><mrow><mi>s</mi></mrow><mrow><mo>+</mo></mrow></msubsup></math> and non-strange D mesons are compatible within the combined statistical and systematic uncertainties. They show, however, a hint of a hierarchy <math><mo>(</mo><msubsup><mrow><mi>R</mi></mrow><mrow><mi>AA</mi></mrow><mrow><msup><mrow><mi>D</mi></mrow><mrow><mn>0</mn></mrow></msup></mrow></msubsup><mo>&lt;</mo><msubsup><mrow><mi>R</mi></mrow><mrow><mi>AA</mi></mrow><mrow><msubsup><mrow><mi>D</mi></mrow><mrow><mi>s</mi></mrow><mrow><mo>+</mo></mrow></msubsup></mrow></msubsup><mo>&lt;</mo><msubsup><mrow><mi>R</mi></mrow><mrow><mi>AA</mi></mrow><mrow><msubsup><mrow><mi>Λ</mi></mrow><mrow><mi>c</mi></mrow><mrow><mo>+</mo></mrow></msubsup></mrow></msubsup><mo>)</mo></math>, conceivable with a contribution from coalescence mechanisms to charm hadron formation in the medium.

F.T. Acosta

H. Beck

H. Bello Martinez

Poland

J. Bhom

production in Pb–Pb collisions at TeV

The measurement of the deuteron and anti-deuteron production in the rapidity range <math><mo>−</mo><mn>1</mn><mo>&lt;</mo><mi>y</mi><mo>&lt;</mo><mn>0</mn></math> as a function of transverse momentum and event multiplicity in p–Pb collisions at <math><msqrt><mrow><msub><mrow><mi>s</mi></mrow><mrow><mi>NN</mi></mrow></msub></mrow></msqrt></math> = 5.02 TeV is presented. (Anti-)deuterons are identified via their specific energy loss <math><mi>d</mi><mi>E</mi><mo>/</mo><mi>d</mi><mi>x</mi></math> 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 particle momenta are extracted from the deuteron spectra and the values are similar to those obtained for p and Λ 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 <math><mmultiscripts><mrow><mi>He</mi></mrow><mprescripts></mprescripts><none></none><mrow><mn>3</mn></mrow></mmultiscripts></math> and <math><mmultiscripts><mrow><mover><mrow><mrow><mi>He</mi></mrow></mrow><mo>‾</mo></mover></mrow><mprescripts></mprescripts><none></none><mrow><mn>3</mn></mrow></mmultiscripts></math> nuclei has been studied. The spectrum corresponding to all non-single diffractive p-Pb collisions is obtained in the rapidity window <math><mo>−</mo><mn>1</mn><mo>&lt;</mo><mi>y</mi><mo>&lt;</mo><mn>0</mn></math> and the <math><msub><mrow><mi>p</mi></mrow><mrow><mi>T</mi></mrow></msub></math>-integrated yield dN/dy is extracted. It is found that the yields of protons, deuterons, and <math><mmultiscripts><mrow><mi>He</mi></mrow><mprescripts></mprescripts><none></none><mrow><mn>3</mn></mrow></mmultiscripts></math>, normalised by the spin degeneracy factor, follow an exponential decrease with mass number.

Multiplicity dependence of light (anti-)nuclei production in p–Pb collisions at TeV

The ALICE collaboration performed the first rapidity-differential measurement of coherent <math><mi>J</mi><mo>/</mo><mi>ψ</mi></math> photoproduction in ultra-peripheral Pb–Pb collisions at a center-of-mass energy <math><msqrt><mrow><msub><mrow><mi>s</mi></mrow><mrow><mi>NN</mi></mrow></msub></mrow></msqrt><mspace width="0.25em"></mspace><mo>=</mo><mspace width="0.25em"></mspace><mn>5.02</mn></math> TeV. The <math><mi>J</mi><mo>/</mo><mi>ψ</mi></math> is detected via its dimuon decay in the forward rapidity region (<math><mo>−</mo><mn>4.0</mn><mo>&lt;</mo><mi>y</mi><mo>&lt;</mo><mo>−</mo><mn>2.5</mn></math>) for events where the hadronic activity is required to be minimal. The analysis is based on an event sample corresponding to an integrated luminosity of about 750 μb$^{−1}$. The cross section for coherent <math><mi>J</mi><mo>/</mo><mi>ψ</mi></math> production is presented in six rapidity bins. The results are compared with theoretical models for coherent <math><mi>J</mi><mo>/</mo><mi>ψ</mi></math> photoproduction. These comparisons indicate that gluon shadowing effects play a role in the photoproduction process. The ratio of <math><msup><mrow><mi>ψ</mi></mrow><mrow><mo>′</mo></mrow></msup></math> to <math><mi>J</mi><mo>/</mo><mi>ψ</mi></math> coherent photoproduction cross sections was measured and found to be consistent with that measured for photoproduction off protons.

Coherent J/ photoproduction at forward rapidity in ultra-peripheral Pb–Pb collisions at TeV

An improved value for the lifetime of the (anti-)hypertriton has been obtained using the data sample of Pb–Pb collisions at <math><msqrt><mrow><msub><mrow><mi>s</mi></mrow><mrow><mi>NN</mi></mrow></msub></mrow></msqrt><mo>=</mo><mn>5.02</mn></math> TeV collected by the ALICE experiment at the LHC. The (anti-)hypertriton has been reconstructed via its charged two-body mesonic decay channel and the lifetime has been determined from an exponential fit to the dN/d(ct) spectrum. The measured value, <math><mi>τ</mi><mo>=</mo><msubsup><mrow><mn>242</mn></mrow><mrow><mo>−</mo><mn>38</mn></mrow><mrow><mo>+</mo><mn>34</mn></mrow></msubsup></math> (stat.) ± 17 (syst.) ps, is compatible with representative theoretical predictions, thus contributing to the solution of the longstanding hypertriton lifetime puzzle.

And lifetime measurement in Pb–Pb collisions at Via Two-body Decay

The jet radial structure and particle transverse momentum (<math><msub><mrow><mi>p</mi></mrow><mrow><mi>T</mi></mrow></msub></math>) composition within jets are presented in centrality-selected Pb–Pb collisions at <math><msqrt><mrow><msub><mrow><mi>s</mi></mrow><mrow><mi>NN</mi></mrow></msub></mrow></msqrt><mo>=</mo><mn>2.76</mn></math> TeV. Track-based jets, which are also called charged jets, were reconstructed with a resolution parameter of <math><mi>R</mi><mo>=</mo><mn>0.3</mn></math> at midrapidity <math><mo>|</mo><msub><mrow><mi>η</mi></mrow><mrow><mi>ch jet</mi></mrow></msub><mo>|</mo><mo>&lt;</mo><mn>0.6</mn></math> for transverse momenta <math><msub><mrow><mi>p</mi></mrow><mrow><mi>T</mi><mo>,</mo><mspace width="0.2em"></mspace><mi>ch jet</mi></mrow></msub><mo>=</mo><mn>30</mn></math>–120 GeV/c. Jet–hadron correlations in relative azimuth and pseudorapidity space (<math><mi>Δ</mi><mi>φ</mi><mo>,</mo><mi>Δ</mi><mi>η</mi></math>) are measured to study the distribution of the associated particles around the jet axis for different <math><msub><mrow><mi>p</mi></mrow><mrow><mi>T</mi><mo>,</mo><mi>assoc</mi></mrow></msub></math>-ranges between 1 and 20 GeV/c. The data in Pb–Pb collisions are compared to reference distributions for pp collisions, obtained using embedded PYTHIA simulations. The number of high-<math><msub><mrow><mi>p</mi></mrow><mrow><mi>T</mi></mrow></msub></math> associate particles (<math><mn>4</mn><mo>&lt;</mo><msub><mrow><mi>p</mi></mrow><mrow><mi>T</mi><mo>,</mo><mi>assoc</mi></mrow></msub><mo>&lt;</mo><mn>20</mn></math> GeV/c) in Pb–Pb collisions is found to be suppressed compared to the reference by 30 to 10%, depending on centrality. The radial particle distribution relative to the jet axis shows a moderate modification in Pb–Pb collisions with respect to PYTHIA. High-<math><msub><mrow><mi>p</mi></mrow><mrow><mi>T</mi></mrow></msub></math> associate particles are slightly more collimated in Pb–Pb collisions compared to the reference, while low-<math><msub><mrow><mi>p</mi></mrow><mrow><mi>T</mi></mrow></msub></math> associate particles tend to be broadened. The results, which are presented for the first time down to <math><msub><mrow><mi>p</mi></mrow><mrow><mi>T</mi><mo>,</mo><mspace width="0.2em"></mspace><mi>ch jet</mi></mrow></msub><mo>=</mo><mn>30</mn></math> GeV/c in Pb–Pb collisions, are compatible with both previous jet–hadron-related measurements from the CMS Collaboration and jet shape measurements from the ALICE Collaboration at higher <math><msub><mrow><mi>p</mi></mrow><mrow><mi>T</mi></mrow></msub></math>, and add further support for the established picture of in-medium parton energy loss.

Measurement of jet radial profiles in Pb–Pb collisions at TeV

This work presents new constraints on the existence and the binding energy of a possible Λ–Λ bound state, the H-dibaryon, derived from Λ–Λ femtoscopic measurements by the ALICE collaboration. The results are obtained from a new measurement using the femtoscopy technique in Image 1 collisions at <math><msqrt><mrow><mi>s</mi></mrow></msqrt><mo>=</mo><mn>13</mn></math> TeV and <math><mi>p</mi><mtext>–</mtext><mrow><mi>Pb</mi></mrow></math> collisions at <math><msqrt><mrow><msub><mrow><mi>s</mi></mrow><mrow><mi>NN</mi></mrow></msub></mrow></msqrt><mo>=</mo><mn>5.02</mn></math> TeV, combined with previously published results from Image 1 collisions at <math><msqrt><mrow><mi>s</mi></mrow></msqrt><mo>=</mo><mn>7</mn></math> TeV. The Λ–Λ scattering parameter space, spanned by the inverse scattering length <math><msubsup><mrow><mi>f</mi></mrow><mrow><mn>0</mn></mrow><mrow><mo>−</mo><mn>1</mn></mrow></msubsup></math> and the effective range <math><msub><mrow><mi>d</mi></mrow><mrow><mn>0</mn></mrow></msub></math>, is constrained by comparing the measured Λ–Λ correlation function with calculations obtained within the Lednický model. The data are compatible with hypernuclei results and lattice computations, both predicting a shallow attractive interaction, and permit to test different theoretical approaches describing the Λ–Λ interaction. The region in the <math><mo>(</mo><msubsup><mrow><mi>f</mi></mrow><mrow><mn>0</mn></mrow><mrow><mo>−</mo><mn>1</mn></mrow></msubsup><mo>,</mo><msub><mrow><mi>d</mi></mrow><mrow><mn>0</mn></mrow></msub><mo>)</mo></math> plane which would accommodate a Λ–Λ bound state is substantially restricted compared to previous studies. The binding energy of the possible Λ–Λ bound state is estimated within an effective-range expansion approach and is found to be <math><msub><mrow><mi>B</mi></mrow><mrow><mi>Λ</mi><mi>Λ</mi></mrow></msub><mo>=</mo><msubsup><mrow><mn>3.2</mn></mrow><mrow><mo>−</mo><mn>2.4</mn></mrow><mrow><mo>+</mo><mn>1.6</mn></mrow></msubsup><msubsup><mrow><mtext>(stat)</mtext></mrow><mrow><mo>−</mo><mn>1.0</mn></mrow><mrow><mo>+</mo><mn>1.8</mn></mrow></msubsup><mtext>(syst)</mtext></math> MeV.

Study of the Λ–Λ interaction with femtoscopy correlations in and p–Pb collisions at the LHC