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• Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo; Agrawal, Nikita & Ahammed, Zubayer [Show all 51 contributors for this article] (2018). J/ψ production as a function of charged-particle pseudorapidity density in p–Pb collisions at √sNN = 5.02 TeV. Physics Letters B. ISSN 0370-2693. 776, p. 91–104. doi: 10.1016/j.physletb.2017.11.008. Full text in Research Archive Show summary

  We report measurements of the inclusive J/ψ yield and average transverse momentum as a function of charged-particle pseudorapidity density dNch/dη in p–Pb collisions at √sNN=5.02 TeV with ALICE at the LHC. The observables are normalised to their corresponding averages in non-single diffractive events. An increase of the normalised J/ψ yield with normalised dNch/dη, measured at mid-rapidity, is observed at mid-rapidity and backward rapidity. At forward rapidity, a saturation of the relative yield is observed for high charged-particle multiplicities. The normalised average transverse momentum at forward and backward rapidities increases with multiplicity at low multiplicities and saturates beyond moderate multiplicities. In addition, the forward-to-backward nuclear modification factor ratio is also reported, showing an increasing suppression of J/ψ production at forward rapidity with respect to backward rapidity for increasing charged-particle multiplicity.

• Acharya, Shreyasi; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 50 contributors for this article] (2018). First measurement of jet mass in Pb–Pb and p–Pb collisions at the LHC. Physics Letters B. ISSN 0370-2693. 776, p. 249–264. doi: 10.1016/j.physletb.2017.11.044. Full text in Research Archive Show summary

  This letter presents the first measurement of jet mass in Pb-Pb and p-Pb collisions at \(\sqrt{s_{\rm NN}}\) = 2.76 TeV and 5.02 TeV, respectively. Both the jet energy and the jet mass are expected to be sensitive to jet quenching in the hot Quantum Chromodynamics (QCD) matter created in nuclear collisions at collider energies. Jets are reconstructed from charged particles using the anti-\(k_{\rm T}\) jet algorithm and resolution parameter \(R = 0.4\), The jets are measured in the pseudorapidity range \(|\eta_{\rm{jet}}|<0.5\) and in three intervals of transverse momentum between 60 GeV/\(c\) and 120 GeV/\(c\), The measurement of the jet mass in central Pb-Pb collisions is compared to the jet mass as measured in p-Pb reference collisions, to vacuum event generators, and to models including jet quenching. It is observed that the jet mass in central Pb-Pb collisions is consistent within uncertainties with p-Pb reference measurements. Furthermore, the measured jet mass in Pb-Pb collisions is not reproduced by the quenching models considered in this letter and is found to be consistent with PYTHIA expectations within systematic uncertainties.

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2017). Insight into particle production mechanisms via angular correlations of identified particles in pp collisions at √s=7 TeV. European Physical Journal C. ISSN 1434-6044. 77:569(8), p. 1–17. doi: 10.1140/epjc/s10052-017-5129-6. Full text in Research Archive Show summary

  Two-particle angular correlations were measured in pp collisions at √s = 7 TeV for pions, kaons, protons, and lambdas, for all particle/anti-particle combinations in the pair. Data for mesons exhibit an expected peak dominated by effects associated with mini-jets and are well reproduced by general purposeMonte Carlo generators. However, for baryon–baryon and anti-baryon–anti-baryon pairs, where both particles have the same baryon number, a near-side anticorrelation structure is observed instead of a peak. This effect is interpreted in the context of baryon production mechanisms in the fragmentation process. It currently presents a challenge to Monte Carlo models and its origin remains an open question.

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2017). J/ψ suppression at forward rapidity in Pb-Pb collisions at √sNN=5.02 TeV. Physics Letters B. ISSN 0370-2693. 766, p. 212–224. doi: 10.1016/j.physletb.2016.12.064. Full text in Research Archive Show summary

  The inclusive J/ψproduction has been studied in Pb–Pb and pp collisions at the centre-of-mass energy per nucleon pair √sNN=5.02TeV, using the ALICE detector at the CERN LHC. The J/ψmeson is reconstructed, in the centre-of-mass rapidity interval 2.5 < y < 4and in the transverse-momentum range pT < 12GeV/c, via its decay to a muon pair. In this Letter, we present results on the inclusive J/ψcross section in pp collisions at √s=5.02TeVand on the nuclear modification factor RAA. The latter is presented as a function of the centrality of the collision and, for central collisions, as a function of the transverse momentum pTof the J/ψ. The measured RAAvalues indicate a suppression of the J/ψin nuclear collisions and are then compared to our previous results obtained in Pb–Pb collisions at √sNN = 2.76TeV. The ratio of the RAAvalues at the two energies is also computed and compared to calculations of tatistical and dynamical models. The numerical value of the ratio for central events (0–10% centrality) is 1.17 ±0.04(stat)±0.20(syst). In central events, as a function of pT, a slight increase of AAwith collision energy is visible in the region 2 < pT < 6GeV/c. Theoretical calculations qualitatively describe the measurements, within uncertainties.

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2017). Charged-particle multiplicities in proton?proton collisions at √s=0.9 to 8 TeV. European Physical Journal C. ISSN 1434-6044. 77:33(1), p. 1–39. doi: 10.1140/epjc/s10052-016-4571-1. Full text in Research Archive Show summary

  A detailed study of pseudorapidity densities and multiplicity distributions of primary charged particles produced in proton–proton collisions, at √s = 0.9, 2.36, 2.76, 7 and 8 TeV, in the pseudorapidity range |η| < 2, was carried out using the ALICE detector. Measurements were obtained for three event classes: inelastic, non-single diffractive and eventswith at least one charged particle in the pseudorapidity interval |η| < 1. The use of an improved track-counting algorithm combined with ALICE’s measurements of diffractive processes allows a higher precision compared to our previous publications. A KNO scaling study was performed in the pseudorapidity intervals |η| < 0.5, 1.0 and 1.5. The data are compared to other experimental results and to models as implemented in Monte Carlo event generators PHOJET and recent tunes of PYTHIA6, PYTHIA8 and EPOS.

• Acharya, Shreyasi; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2017). Production of muons from heavy-flavour hadron decays in p–Pb collisions at √sNN=5.02 TeV. Physics Letters B. ISSN 0370-2693. 770(2017), p. 459–472. doi: 10.1016/j.physletb.2017.03.049. Full text in Research Archive Show summary

  The production of muons from heavy-flavour hadron decays in p–Pb collisions at √sNN = 5.02TeV was studied for 2 < pT < 16GeV/c with the ALICE detector at the CERN LHC. The measurement was performed at forward (p-going direction) and backward (Pb-going direction) rapidity, in the ranges of rapidity in the centre-of-mass system (cms) 2.03 < ycms < 3.53and −4.46 < ycms < −2.96, respectively. The production cross sections and nuclear modification factors are presented as a function of transverse momentum (pT). At forward rapidity, the nuclear modification factor is compatible with unity while at backward rapidity, in the interval 2.5 < pT < 3.5 GeV/c, it is above unity by more than 2σ. The ratio of the forward-to-backward production cross sections is also measured in the overlapping interval 2.96 < |ycms| < 3.53 and is smaller than unity by 3.7 σin 2.5 < pT < 3.5 GeV/c. The data are described by model calculations including cold nuclear matter effects.

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2017). Anomalous evolution of the near-side jet peak shape in Pb-Pb collisions at √sNN=2.76 TeV. Physical Review Letters. ISSN 0031-9007. 119:102301(10). doi: 10.1103/PhysRevLett.119.102301. Full text in Research Archive Show summary

  We present the charged-particle pseudorapidity density in pp, p–Pb, and Pb–Pb collisions at √sNN = 5.02 TeV over a broad pseudorapidity range. The distributions are determined using the same experimental apparatus and methodologies, thereby minimizing systematic uncertainties, and providing clear and model-independent observations on the systemsize dependence of the particle production at relativistic energies. An increase of particle production in Pb–Pb collisions near mid-rapidity, relative to p collisions, is observed. The relative linearity in p–Pb collisions of the ratio to the smaller system indicate a coherent particle production throughout the longitudinal extend of the collision zone.

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, G Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 46 contributors for this article] (2017). Determination of the event collision time with the ALICE detector at the LHC. The European Physical Journal Plus. 132(99), p. 1–17. doi: 10.1140/epjp/i2017-11279-1. Full text in Research Archive Show summary

  Particle identification is an important feature of the ALICE detector at the LHC. In particular, for particle identification via the time-of-flight technique, the precise determination of the event collision time represents an important ingredient of the quality of the measurement. In this paper, the different methods used for such a measurement in ALICE by means of the T0 and the TOF detectors are reviewed. Efficiencies, resolution and the improvement of the particle identification separation power of the methods used are presented for the different LHC colliding systems (pp, p-Pb and Pb-Pb) during the first period of data taking of LHC (RUN 1).

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, G Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 48 contributors for this article] (2017). W and Z boson production in p-Pb collisions at √sNN = 5.02 TeV. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 77, p. 1–26. doi: 10.1007/JHEP02(2017)077. Full text in Research Archive Show summary

  The W and Z boson production was measured via the muonic decay channel in proton-lead collisions at √sNN = 5:02 TeV at the Large Hadron Collider with the ALICE detector. The measurement covers backward (-4:46 < ycms < -2:96) and forward (2:03 < ycms < 3:53) rapidity regions, corresponding to Pb-going and p-going directions, respectively. The Z-boson production cross section, with dimuon invariant mass of 60 < m pp < 120 GeV/c2 and muon transverse momentum (pT) larger than 20 GeV/c, is measured. The production cross section and charge asymmetry of muons from W-boson decays with p_T > 10 GeV/c are determined. The results are compared to theoretical calculations both with and without including the nuclear modi_cation of the parton distribution functions. The W-boson production is also studied as a function of the collision centrality: the cross section of muons from W-boson decays is found to scale with the average number of binary nucleon-nucleon collisions within uncertainties.

• Acharya, Shreyasi; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2017). Measurement of D-meson production at mid-rapidity in pp collisions at √s = 7 TeV. European Physical Journal C. ISSN 1434-6044. 77:550(8), p. 1–21. doi: 10.1140/epjc/s10052-017-5090-4. Full text in Research Archive Show summary

  The production cross sections for prompt charmed mesons D0, D+, D∗+ and D+ s were measured at mid-rapidity in proton–proton collisions at a centre-of-mass energy √s = 7 TeV with the ALICE detector at the Large Hadron Collider (LHC). D mesons were reconstructed from their decays D0 → K− π +, D+ → K− π + π +, D∗+ → D0π +, D+ s → φπ + → K−K+ π +, and their charge conjugates. With respect to previous measurements in the same rapidity region, the coverage in transverse momentum (pT) is extended and the uncertainties are reduced by a factor of about two. The accuracy on the estimated total cc production cross section is likewise improved. The measured pT differential cross sections are compared with the results of three perturbative QCD calculations.

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2017). Measurement of the production of high-pT electrons from heavy-flavour hadron decays in Pb-Pb collisions at √sNN=2.76 TeV. Physics Letters B. ISSN 0370-2693. 771, p. 467–481. doi: 10.1016/j.physletb.2017.05.060. Full text in Research Archive Show summary

  Electrons from heavy-flavour hadron decays (charm and beauty) were measured with the ALICE detector in Pb–Pbcollisions at a centre-of-mass of energy √sNN = 2.76TeV. The transverse momentum (pT) differential production yields at mid-rapidity were used to calculate the nuclear modification factor RAAin the interval 3 < pT < 18GeV/c. The RAAshows a strong suppression compared to binary scaling of pp collisions at the same energy (up to a factor of 4) in the 10% most central Pb–Pbcollisions. There is a centrality trend of suppression, and a weaker suppression (down to a factor of 2) in semi-peripheral (50–80%) collisions is observed. The suppression of electrons in this broad pTinterval indicates that both charm and beauty quarks lose energy when they traverse the hot medium formed in Pb–Pb collisions at LHC.

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2017). K∗(892)0 and ϕ(1020) meson production at high transverse momentum in pp and Pb-Pb collisions at √sNN=2.76 TeV. Physical Review C. ISSN 2469-9985. 95:064606(6), p. 1–18. doi: 10.1103/PhysRevC.95.064606. Full text in Research Archive Show summary

  The production of K∗(892)0 and ϕ(1020) mesons in proton-proton (pp) and lead-lead (Pb-Pb) collisions at √sNN=2.76TeV has been analyzed using a high luminosity data sample accumulated in 2011 with the ALICE detector at the Large Hadron Collider (LHC). Transverse momentum (pT) spectra have been measured for K∗(892)0 and ϕ(1020) mesons via their hadronic decay channels for pT up to 20GeV/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 pT due to rescattering of its decay products in the hadronic phase. In central Pb-Pb collisions the pT dependent ϕ(1020)/π and K∗(892)0/π ratios show an enhancement over pp collisions for pT≈3GeV/c, consistent with previous observations of strong radial flow. At high pT, 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 ϕ(1020) mesons is suppressed for pT>8GeV/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.

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2017). Enhanced production of multi-strange hadrons in high-multiplicity proton-proton collisions. Nature Physics. ISSN 1745-2473. 13(6), p. 535–539. doi: 10.1038/nphys4111. Full text in Research Archive Show summary

  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 exotic state of strongly interacting quantum chromodynamics matter is produced in the laboratory in heavy nuclei high-energy collisions, where an enhanced production of strange hadrons is observed2, 3, 4, 5, 6. Strangeness enhancement, originally proposed as a signature of QGP formation in nuclear collisions7, is more pronounced for multi-strange baryons. Several effects typical of heavy-ion phenomenology have been observed in high-multiplicity proton–proton (pp) collisions8, 9, but the enhanced production of multi-strange particles has not been reported so far. Here we present the first observation of strangeness enhancement in high-multiplicity proton–proton 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 the p–Pb collision results10, 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.

• Acharya, Shreyasi; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 50 contributors for this article] (2017). Production of π0 and η mesons up to high transverse momentum in pp collisions at √s=2.76 TeV. European Physical Journal C. ISSN 1434-6044. 77:339(5), p. 1–25. doi: 10.1140/epjc/s10052-017-4890-x. Full text in Research Archive Show summary

  The invariant differential cross sections for inclusive π0 and η mesons at midrapidity were measured in pp collisions at √s = 2.76 TeV for transverse momenta 0.4 < pT < 40 GeV/c and 0.6 < pT < 20 GeV/c, respectively, using the ALICE detector. This large range in pT was achieved by combining various analysis techniques and different triggers involving the electromagnetic calorimeter (EMCal). In particular, a newsingle-cluster, shower-shape based method was developed for the identification of highpT neutral pions, which exploits that the showers originating from their decay photons overlap in the EMCal. Above 4 GeV/c, the measured cross sections are found to exhibit a similar power-law behavior with an exponent of about 6.3. Next-to-leading-order perturbative QCD calculations differ from the measured cross sections by about 30% for the π0, and between 30–50% for the η meson, while generator-level simulations with PYTHIA 8.2 describe the data to better than 10–30%, except at pT < 1 GeV/c. The new data can therefore be used to further improve the theoretical description of π0 and η meson production.

• Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo; Agrawal, Nikita & Ahammed, Zubayer [Show all 51 contributors for this article] (2017). Production of Σ(1385)± and Ξ(1530)0 in p–Pb collisions at √sNN=5.02 TeV. European Physical Journal C. ISSN 1434-6044. 77:389(6), p. 1–17. doi: 10.1140/epjc/s10052-017-4943-1. Full text in Research Archive Show summary

  The transverse momentum distributions of the strange and double-strange hyperon resonances ( (1385) ±, (1530)0) produced in p–Pb collisions at √sNN = 5.02 TeV were measured in the rapidity range −0.5 < yCMS < 0 for event classes corresponding to different charged-particle multiplicity densities, dNch/dηlab . The mean transverse momentumvalues are presented as a function of dNch/dηlab , as well as a function of the particle masses and compared with previous results on hyperon production. The integrated yield ratios of excited to ground-state hyperons are constant as a function of dNch/dηlab . The equivalent ratios to pions exhibit an increase with dNch/dηlab , depending on their strangeness content.

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 50 contributors for this article] (2017). Measurement of electrons from beauty-hadron decays in p-Pb collisions at √sNN=5.02 TeV and Pb-Pb collisions at √sNN=2.76 TeV. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 2017:052(7), p. 1–39. doi: 10.1007/JHEP07(2017)052. Full text in Research Archive Show summary

  The production of beauty hadrons was measured via semi-leptonic decays at mid-rapidity with the ALICE detector at the LHC in the transverse momentum interval 1 < pT < 8 GeV/c in minimum-bias p-Pb collisions at √sNN = 5.02 TeV and in 1.3 < pT < 8 GeV/c in the 20% most central Pb-Pb collisions at √sNN = 2.76TeV. The pp reference spectra at √s = 5.02 TeV and √s = 2.76 TeV, needed for the calculation of the nuclear modification factors RpPb and RPbPb, were obtained by a pQCD-driven scaling of the cross section of electrons from beauty-hadron decays measured at √s = 7 TeV. In the pT interval 3 < pT < 8 GeV/c, a suppression of the yield of electrons from beauty-hadron decays is observed in Pb-Pb compared to pp collisions. Towards lower pT, the RPbPb values increase with large systematic uncertainties. The RpPb is consistent with unity within systematic uncertainties and is well described by theoretical calculations that include cold nuclear matter effects in p-Pb collisions. The measured RpPb and these calculations indicate that cold nuclear matter effects are small at high transverse momentum also in Pb-Pb collisions. Therefore, the observed reduction of RPbPb below unity at high pT may be ascribed to an effect of the hot and dense medium formed in Pb-Pb collisions.

• Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo; Agrawal, Nikita & Ahammed, Zubayer [Show all 51 contributors for this article] (2017). Azimuthally differential pion femtoscopy in Pb-Pb collisions at √sNN=2.76  TeV. Physical Review Letters. ISSN 0031-9007. 118:222301(22), p. 1–12. doi: 10.1103/PhysRevLett.118.222301. Full text in Research Archive Show summary

  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 √sNN = 2.76 TeV. The measurements have been performed in the centrality range 0%–50% and for pion pair transverse momenta 0.2 < kT < 0.7 GeV/c. We find that the Rside and Rout 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. The final-state source eccentricity, estimated via Rside 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 Rside oscillations, but systematically underestimate the oscillation magnitude.

• Acharya, Shreyasi; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2017). Energy dependence of forward-rapidity J/ψ and ψ(2S) production in pp collisions at the LHC. European Physical Journal C. ISSN 1434-6044. 77:392(6), p. 1–21. doi: 10.1140/epjc/s10052-017-4940-4. Full text in Research Archive Show summary

  We present results on transverse momentum (pt) and rapidity (y) differential production cross sections, mean transverse momentum and mean transverse momentum square of inclusive J/ψ and ψ(2S) at forward rapidity (2.5 < y < 4) as well as ψ(2S)-to-J/ψ cross section ratios. These quantities are measured in pp collisions at center of mass energies √s = 5.02 and 13 TeV with the ALICE detector. Both charmonium states are reconstructed in the dimuon decay channel, using the muon spectrometer. Acomprehensive comparison to inclusive charmonium cross sections measured at √s = 2.76, 7 and 8 TeV is performed. A comparison to non-relativistic quantum chromodynamics and fixed-order next-to-leading logarithm calculations, which describe prompt and non-prompt charmonium production respectively, is also presented. A good description of the data is obtained over the full pt range, provided that both contributions are summed. In particular, it is found that for pt > 15 GeV/c the non-prompt contribution reaches up to 50% of the total charmonium yield.

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2017). Evolution of the longitudinal and azimuthal structure of the near-side jet peak in Pb-Pb collisions at √sNN=2.76 TeV. Physical Review C. ISSN 2469-9985. 96:034904(3), p. 1–18. doi: 10.1103/PhysRevC.96.034904. Full text in Research Archive Show summary

  In two-particle angular correlation measurements, jets give rise to a near-side peak, formed by particles associated to a higher-pT trigger particle. Measurements of these correlations as a function of pseudorapidity (_η) and azimuthal (_ϕ) differences are used to extract the centrality and pT dependence of the shape of the near-side peak in the pT range 1 < pT < 8 GeV/c in Pb-Pb and pp collisions at √sNN= 2.76 TeV. A combined fit of the near-side peak and long-range correlations is applied to the data and the peak shape is quantified by the variance of the distributions. While the width of the peak in the _ϕ direction is almost independent of centrality, a significant broadening in the _η direction is found from peripheral to central collisions. This feature is prominent for the low-pT region and vanishes above 4 GeV/c. The widths measured in peripheral collisions are equal to those in pp collisions in the _ϕ direction and above 3 GeV/c in the _η direction. Furthermore, for the 10% most central collisions and 1 < pT,assoc < 2 GeV/c, 1 < pT,trig < 3 GeV/c, a departure from a Gaussian shape is found: a depletion develops around the center of the peak. The results are compared to A Multi-Phase Transport (AMPT) model simulation as well as other theoretical calculations indicating that the broadening and the development of the depletion are connected to the strength of radial and longitudinal flow.

• Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agrawal, Nikita; Ahammed, Zubayer & Ahmad, Shafiq F. [Show all 51 contributors for this article] (2017). Centrality dependence of the pseudorapidity density distribution for charged particles in Pb-Pb collisions at √sNN=5.02TeV. Physics Letters B. ISSN 0370-2693. 772, p. 567–577. doi: 10.1016/j.physletb.2017.07.017. Full text in Research Archive Show summary

  We present the charged-particle pseudorapidity density in Pb–Pb collisions at sNN=5.02TeV in centrality classes measured by ALICE. The measurement covers a wide pseudorapidity range from −3.5 to 5, which is sufficient for reliable estimates of the total number of charged particles produced in the collisions. For the most central (0–5%) collisions we find 21400±1300, while for the most peripheral (80–90%) we find 230±38. This corresponds to an increase of (27±4)% over the results at sNN=2.76TeV previously reported by ALICE. The energy dependence of the total number of charged particles produced in heavy-ion collisions is found to obey a modified power-law like behaviour. The charged-particle pseudorapidity density of the most central collisions is compared to model calculations — none of which fully describes the measured distribution. We also present an estimate of the rapidity density of charged particles. The width of that distribution is found to exhibit a remarkable proportionality to the beam rapidity, independent of the collision energy from the top SPS to LHC energies.

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2017). φ-meson production at forward rapidity in p–Pb collisions at √sNN=5.02 TeV and in pp collisions at √s=2.76 TeV. Physics Letters B. ISSN 0370-2693. 768, p. 203–217. doi: 10.1016/j.physletb.2017.01.074. Full text in Research Archive Show summary

  The first study of φ-meson production in p–Pb collisions at forward and backward rapidity, at nucleon–nucleon centre-of-mass energy √sNN=5.02TeV, has been performed with the ALICE apparatus at the LHC. The φ-mesons have been identified in the dimuon decay channel in he transverse momentum (pT) range 1 < pT < 7 GeV/c, both in the p-going (2.03 < y < 3.53) and the Pb-going ( −4.46 < y < −2.96) directions — where ystands for the rapidity in the ucleon–nucleon centre-of-mass — the integrated luminosity amounting to 5.01 ±0.19nb−1and 5.81 ±0.20nb−1, respectively, for the two data sam-ples. Differential cross sections as a function of transverse momentum and rapidity are presented. The forward–backward ratio for φ-meson production is measured for 2.96 <|y| <3.53, resulting in a ratio ∼0.5with no ignificant pTdependence within the uncertainties. The pTdependence of the φnuclear modification factor RpPbexhibits an enhancement up to a factor1.6 at pT=3–4GeV/cin the Pb-going direction. The pTdependence of the φ-meson cross section in pp collisions at √s=2.76TeV, which is used to determine a reference for the p–Pb results, is also presented here for 1 < pT < 5GeV/cand 2.5

• Acharya, Shreyasi; Adam, Jaroslav; Adamová, Dagmar; Adolfsson, Jonatan; Aggarwal, Madan M. & Rinella, G Aglieri [Show all 53 contributors for this article] (2017). Measurements of the dielectron continuum in pp, p-Pb and Pb-Pb collisions with ALICE at the LHC. Nuclear Physics A. ISSN 0375-9474. 967(2017), p. 684–687. doi: 10.1016/j.nuclphysa.2017.04.037. Full text in Research Archive Show summary

  Dielectrons produced in ultra-relativistic heavy-ion collisions provide a unique probe of the whole system evolution as they are unperturbed by final-state interactions. The dielectron continuum is extremely rich in physics sources: thermal radiation is of particular interest as it carries information about the temperature of the hot and dense system created in such collisions. The dielectron invariant mass distribution is sensitive to medium modifications of the spectral function of vector mesons that are linked to the potential restoration of chiral symmetry. Correlated electron pairs from semi-leptonic charm and beauty decays provide information about the heavy-quark energy loss.

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2017). Measurement of azimuthal correlations of D mesons with charged particles in pp collisions at √s=7 TeV and p-Pb collisions at √sNN=5.02 TeV. European Physical Journal C. ISSN 1434-6044. 77:245(4), p. 1–24. doi: 10.1140/epjc/s10052-017-4779-8. Full text in Research Archive Show summary

  The azimuthal correlations of D mesons with charged particles were measured with the ALICE apparatus in pp collisions at √s = 7 TeV and p–Pb collisions at √sNN = 5.02 TeV at the Large Hadron Collider. D0, D+, and D∗+ mesons and their charge conjugates with transverse momentum 3 < pT < 16 GeV/c and rapidity in the nucleonnucleon centre-of-mass system |ycms| < 0.5 (pp collisions) and −0.96 < ycms < 0.04 (p–Pb collisions) were correlated to charged particles with pT > 0.3 GeV/c. The yield of charged particles in the correlation peak induced by the jet containing the D meson and the peak width are compatible within uncertainties in the two collision systems. The data are described within uncertainties by Monte-Carlo simulations based on PYTHIA, POWHEG, and EPOS 3 event generators.

• Acharya, Shreyasi; Adam, Jaroslav; Adamová, Dagmar; Adolfsson, Jonatan; Aggarwal, Madan M. & Rinella, G Aglieri [Show all 53 contributors for this article] (2017). Neutral meson production and correlation with charged hadrons in pp and Pb-Pb collisions with the ALICE experiment at the LHC. Nuclear Physics A. ISSN 0375-9474. 967(2017), p. 688–691. doi: 10.1016/j.nuclphysa.2017.06.052. Full text in Research Archive Show summary

  Among the probes used to investigate the properties of the Quark-Gluon Plasma, the measurement of the energy loss of high-energy partons can be used to put constraints on energy-loss models and to ultimately access medium characteristics, such as the energy density or the temperature. The study of two-particle correlations allows us to obtain very different constraints compared to the nuclear modification factor. In particular, the correlation of charged hadrons with high energy \(\pi^{0}\) or direct photons is believed to give a measurement of the parton energy loss and insights into the medium-induced modification of the fragmentation process. High energy neutral pions are reconstructed using the ALICE electromagnetic calorimeters EMCal and PHOS, and the charged particles are detected by the main tracking detectors ITS and TPC. In these proceedings, the measurement of neutral mesons at \(\sqrt{s} = \(2.76 TeV in pp collisions are presented, as well as the measurements of azimuthal \(\pi^{0}\).hadron correlations in pp and Pb-Pb collisions at \(\sqrt{s_{\rm{NN}}} = 2.76\) TeV, and the extracted per-trigger yield modification factor \(I_{AA}\) . Comparisons with theoretical model calculations are also added.

• Acharya, Shreyasi; Adamová, Dagmar; Adolfsson, Jonatan; Aggarwal, Madan M.; Rinella, G Aglieri & Agnello, Michelangelo [Show all 50 contributors for this article] (2017). Searches for transverse momentum dependent flow vector fluctuations in Pb-Pb and p-Pb collisions at the LHC. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 32, p. 1–32. doi: 10.1007/JHEP09(2017)032. Full text in Research Archive Show summary

  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.

• Acharya, Shreyasi; Adam, Jaroslav; Adamová, Dagmar; Adolfsson, Jonatan; Aggarwal, Madan M. & Rinella, G Aglieri [Show all 51 contributors for this article] (2017). Direct photon measurements in pp and Pb-Pb collisions with the ALICE experiment. Nuclear Physics A. ISSN 0375-9474. 967(2017), p. 696–699. doi: 10.1016/j.nuclphysa.2017.05.094. Full text in Research Archive Show summary

  Direct photon production in heavy-ion collisions provides a valuable set of observables to study the hot QCD medium. The direct photons are produced at different stages of the collision and escape the medium unaffected. In heavy-ion collisions, the direct photon yield at high transverse momentum ( pT>5GeV/c ) is dominated by prompt photons produced in hard scattering of incoming partons and provides information on nuclear parton distribution functions and on the initial parton dynamics. The low momentum component ( pT≲5GeV/c ) of the direct photon production is dominated by thermal radiation by the hot and dense matter created, carrying information on its space-time evolution, collective flow and temperature.

• Acharya, Shreyasi; Adam, Jaroslav; Adamová, Dagmar; Adolfsson, Jonatan; Aggarwal, Madan M. & Rinella, G Aglieri [Show all 52 contributors for this article] (2017). The new Inner Tracking System of the ALICE experiment. Nuclear Physics A. ISSN 0375-9474. 967(2017), p. 900–903. doi: 10.1016/j.nuclphysa.2017.05.069. Full text in Research Archive Show summary

  The ALICE experiment will undergo a major upgrade during the next LHC Long Shutdown scheduled in 2019&ndash;20 that will enable a detailed study of the properties of the QGP, exploiting the increased Pb-Pb luminosity expected during Run 3 and Run 4. The replacement of the existing Inner Tracking System with a completely new ultra-light, high-resolution detector is one of the cornerstones within this upgrade program. The main motivation of the ITS upgrade is to provide ALICE with an improved tracking capability and impact parameter resolution at very low transverse momentum, as well as to enable a substantial increase of the readout rate. The new ITS will consist of seven layers of innovative Monolithic Active Pixel Sensors with the innermost layer sitting at only 23 mm from the interaction point. This talk will focus on the design and the physics performance of the new ITS, as well as the technology choices adopted. The status of the project and the results from the prototypes characterization will also be presented.

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2017). Flow dominance and factorization of transverse momentum correlations in Pb-Pb collisions at the LHC. Physical Review Letters. ISSN 0031-9007. 118:162302(16), p. 1–12. doi: 10.1103/PhysRevLett.118.162302. Full text in Research Archive Show summary

  We present the first measurement of the two-particle transverse momentum differential correlation function, \(P_2\equiv\langle \Delta p_{\rm T} \Delta p_{\rm T} \rangle /\langle p_{\rm T} \rangle^2\). in Pb-Pb collisions at \(\sqrt{s_{_{\rm NN}}} =\) 2.76 TeV. Results for \(P_2\) are reported as a function of relative pseudorapidity \(\Delta \eta\) and azimuthal angle \(\Delta \varphi\) between two particles for different collision centralities. The \(\Delta \phi\) dependence is found to be largely independent of \(\Delta \eta\) for \(|\Delta \eta| \geq\) 0.9. In 5% most central Pb-Pb collisions, the two-particle transverse momentum correlation function exhibits a clear double-hump structure around \(\Delta \varphi = \pi\) (i.e., on the away side), which is not observed in number correlations in the same centrality range, and thus provides an indication of the dominance of triangular flow in this collision centrality. Fourier decompositions of \(P_2\). studied as a function of collision centrality, show that correlations at \(|\Delta \eta| \geq\) 0.9 can be well reproduced by a flow ansatz based on the notion that measured momentum correlations are strictly determined by the collective motion of the system.

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2016). Longitudinal Asymmetry and its Measurable Effects in Pb–Pb Collisions at 2.76 TeV. Nuclear Physics A. ISSN 0375-9474. 956, p. 324–327. doi: 10.1016/j.nuclphysa.2016.03.021. Full text in Research Archive Show summary

  Collisions of identical nuclei at finite impact parameter have an unequal number of participating nucleons from each nucleus due to fluctuations. The event-by-event fluctuations have been estimated by measuring the difference of energy in the zero-degree calorimeters on either side of interaction vertex. The fluctuations affect the global variables such as the rapidity distributions, and the effect has been correlated with a measure of these fluctuations

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2016). (Anti-)deuteron production and anisotropic flow measured with ALICE at the LHC. Nuclear Physics A. ISSN 0375-9474. 956, p. 264–267. doi: 10.1016/j.nuclphysa.2016.01.038. Full text in Research Archive Show summary

  The high abundance of (anti-)deuterons in the statistics gathered in Run 1 of the LHC and the excellent performance of the ALICE setup allow for the simultaneous measurement of the elliptic flow and the deuteron production rates with a large transverse momentum (pT) reach. The (anti-) deuterons are identified using the specific energy loss in the time projection chamber and the velocity information in the time-of-flight detector. The elliptic flow of (anti-)deuterons can provide insight into the production mechanisms of particles in heavy-ion collisions. Quark coalescence is one of the approaches to describe the elliptic flow of hadrons, while the production of light nuclei can be also depicted as a coalescence of nucleons. In these proceedings, the measured v2 of deuterons produced in Pb–Pb collisions at View the MathML sourcesNN=2.76 TeV will be compared to expectations from coalescence and hydrodynamic models

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2016). Measurements of correlations of anisotropic flow harmonics in Pb–Pb Collisions with ALICE. Nuclear Physics A. ISSN 0375-9474. 956, p. 296–299. doi: 10.1016/j.nuclphysa.2016.01.018. Full text in Research Archive Show summary

  We report the first measurements of the correlation strength between various anisotropic flow harmonics, using ALICE data. This correlation strength is characterized with multi-particle cumulants of mixed harmonics, which by construction depend only on the fluctuations of magnitudes of the anisotropic flow vectors. A detailed comparison to theoretical model calculations, including HIJING, Monte Carlo Glauber and hydrodynamics is also presented. These studies further constrain initial conditions, the properties and the evolution of the system to be used in theoretical simulations of heavy-ion collisions.

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2016). Femtoscopy of identified particles in Pb–Pb collisions with ALICE at the LHC. Nuclear Physics A. ISSN 0375-9474. 956, p. 373–376. doi: 10.1016/j.nuclphysa.2016.04.029. Full text in Research Archive Show summary

  Femtoscopy provides information on system size and its dynamics due to the effects of quantum statistics and final-state interactions. The results of femtoscopic correlations of different identified particles measured by ALICE in Pb–Pb collisions at View the MathML sourcesNN=2.76 TeV are presented. Hydrodynamic models predict a decrease of the radii with increasing pair transverse mass (mT) due to radial flow. Correlation measurements of heavy particles extend the range over which the transverse mass dependence of the source radii can be studied and thus can serve as a tool to learn about the dynamics of the deconfined medium. In particular, the measured three-dimensional radii of kaons are compared with a model where the hydrodynamic phase is succeeded by a hadronic rescattering phase and a purely hydrodynamical calculation. The latter predicts an approximate mT scaling of source radii obtained from pion and kaon correlations. This mT scaling appears to be broken in the data. The breaking of scaling is well reproduced by the full hydro-kinetic model calculations, thereby indicating the importance of the rescattering phase at LHC energies. The emission duration and the decoupling time of the system are also estimated for kaons and pions

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2016). Higher harmonic anisotropic flow of identified particles in Pb–Pb collisions with the ALICE detector. Nuclear Physics A. ISSN 0375-9474. 956, p. 304–307. doi: 10.1016/j.nuclphysa.2016.03.031. Full text in Research Archive Show summary

  Anisotropic flow plays a crucial role in establishing the equation of state of the Quark Gluon Plasma. The results at RHIC and LHC have demonstrated that the matter created in heavy-ion collisions behaves as a nearly perfect fluid reflected in the low value of the shear viscosity over entropy density ratio (η/sη/s). The higher flow harmonics are particularly sensitive to the value of η/sη/s in hydrodynamic calculations. In this analysis, we present the first ALICE results on the pT differential v2, v3 and v4 for View the MathML sourceπ±,K±,p(p‾) from the high statistics 2011 heavy-ion run. We investigate how these vn coefficients evolve with particle mass and centrality for the 0–1% and 20–30% centrality ranges. These new measurements aim at differentiating between models that use different initial conditions, constraining further the value of η/sη/s and allowing to decouple the influence of the late hadronic stage from the hydrodynamic evolution of the system

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 980 contributors for this article] (2016). Measurement of an excess in the Yield of J/ψ at very low pT in Pb-Pb collisions at √sNN=2.76 TeV. Physical Review Letters. ISSN 0031-9007. 116(22). doi: 10.1103/PhysRevLett.116.222301. Full text in Research Archive Show summary

  We report on the first measurement of an excess in the yield of J/ψ at very low transverse momentum (pT<0.3  GeV/c) in peripheral hadronic Pb-Pb collisions at √sNN=2.76  TeV, performed by ALICE at the CERN LHC. Remarkably, the measured nuclear modification factor of J/ψ in the rapidity range 2.5

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2016). Centrality dependence of charged jet production in p–Pb collisions at √sNN = 5.02 TeV. European Physical Journal C. ISSN 1434-6044. 76:271(5). doi: 10.1140/epjc/s10052-016-4107-8. Full text in Research Archive Show summary

  Measurements of charged jet production as a function of centrality are presented for p–Pb collisions recorded at√sNN = 5.02TeVwith theALICEdetector. 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-kT 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.

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 990 contributors for this article] (2016). Centrality Dependence of the Charged-Particle Multiplicity Density at Midrapidity in Pb-Pb Collisions at √sNN =5.02 TeV. Physical Review Letters. ISSN 0031-9007. 116(22). doi: 10.1103/PhysRevLett.116.222302. Full text in Research Archive Show summary

  The pseudorapidity density of charged particles, dNch/dη, at midrapidity in Pb-Pb collisions has been measured at a center-of-mass energy per nucleon pair of √sNN=5.02  TeV. For the 5% most central collisions, we measure a value of 1943±54. The rise in dNch/dη as a function of √sNN is steeper than that observed in proton-proton collisions and follows the trend established by measurements at lower energy. The increase of dNch/dη as a function of the average number of participant nucleons, ⟨Npart⟩, calculated in a Glauber model, is compared with the previous measurement at √sNN=2.76  TeV. A constant factor of about 1.2 describes the increase in dNch/dη from √sNN=2.76 to 5.02 TeV for all centrality classes, within the measured range of 0%–80% centrality. The results are also compared to models based on different mechanisms for particle production in nuclear collisions.

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 52 contributors for this article] (2016). Upgrade of the ALICE Inner Tracking System. Nuclear Physics A. ISSN 0375-9474. 956, p. 866–869. doi: 10.1016/j.nuclphysa.2016.02.061. Full text in Research Archive
• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2016). Measurement of transverse energy at midrapidity in Pb-Pb collisions at √sNN =2.76 TeV. Physical Review C. Nuclear Physics. ISSN 0556-2813. 94:034903(3). doi: 10.1103/PhysRevC.94.034903. Full text in Research Archive Show summary

  We report the transverse energy (ET) measured with ALICE at midrapidity in Pb-Pb collisions at √sNN = 2.76 TeV as a function of centrality. The transverse energy was measured using identified single-particle tracks. The measurement was cross checked using the electromagnetic calorimeters and the transverse momentum distributions of identified particles previously reported by ALICE. The results are compared to theoretical models as well as to results from other experiments. The mean ET per unit pseudorapidity (η), _dET/dη_, in 0%–5% central collisions is 1737 ± 6(stat.) ± 97(sys.) GeV. We find a similar centrality dependence of the shape of _dET/dη_ as a function of the number of participating nucleons to that seen at lower energies. The growth in _dET/dη_ at the LHC energies exceeds extrapolations of low-energy data. We observe a nearly linear scaling of _dET/dη_ with the number of quark participants. With the canonical assumption of a 1 fm/c formation time, we estimate that the energy density in 0%–5% central Pb-Pb collisions at √sNN = 2.76 TeV is 12.3 ± 1.0 GeV/fm3 and that he energy density at the most central 80 fm2 of the collision is at least 21.5 ± 1.7 GeV/fm3. This is roughly 2.3 times that observed in 0%–5% central Au-Au collisions at √sNN = 200 GeV.

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2016). Higher harmonic flow coefficients of identified hadrons in Pb-Pb collisions at √sNN=2.76 TeV. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 2016:164(9). doi: 10.1007/JHEP09(2016)164. Full text in Research Archive Show summary

  The elliptic, triangular, quadrangular and pentagonal anisotropic flow coefficients for n_, K_ and p+p in Pb-Pb collisions at √sNN = 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 identi_ed hadrons with reference particles from a different pseudorapidity region. E_ects not related to the common event symmetry planes (non-ow) were estimated using correlations in pp collisions and were subtracted from the measurement. The obtained ow coe_cients exhibit a clear mass ordering for transverse momentum (pT) values below _ 3 GeV/c. In the intermediate pT region (3 < pT < 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 pT < 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 _reball using a value of 0.08 for the ratio of shear viscosity to entropy density (_=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 pT and of coalescence as a particle production mechanism for the particle type grouping at intermediate values of pT for all harmonics.

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 52 contributors for this article] (2016). Elliptic flow of muons from heavy-flavour hadron decays at forward rapidity in Pb-Pb collisions at √sNN = 2.76 TeV. Physics Letters B. ISSN 0370-2693. 753, p. 41–56. doi: 10.1016/j.physletb.2015.11.059. Full text in Research Archive
• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2016). Direct photon production in Pb-Pb collisions at √sNN = 2.76 TeV. Physics Letters B. ISSN 0370-2693. 754, p. 235–248. doi: 10.1016/j.physletb.2016.01.020. Full text in Research Archive
• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2016). Forward-central two-particle correlations in p-Pb collisions at √sNN = 5.02 TeV. Physics Letters B. ISSN 0370-2693. 753, p. 126–139. doi: 10.1016/j.physletb.2015.12.010. Full text in Research Archive Show summary

  Two-particle angular correlations between trigger particles in the forward pseudorapidity range (2.5<|η|<4.0) and associated particles in the central range (|η|<1.0) are measured with the ALICE detector in p–Pb collisions at a nucleon–nucleon centre-of-mass energy of 5.02 TeV. The trigger particles are reconstructed using the muon spectrometer, and the associated particles by the central barrel tracking detectors. In high-multiplicity events, the double-ridge structure, previously discovered in two-particle angular correlations at midrapidity, is found to persist to the pseudorapidity ranges studied in this Letter. The second-order Fourier coefficients for muons in high-multiplicity events are extracted after jet-like correlations from low-multiplicity events have been subtracted. The coefficients are found to have a similar transverse momentum (pT) dependence in p-going (p–Pb) and Pb-going (Pb–p) configurations, with the Pb-going coefficients larger by about 16±6%, rather independent of pT within the uncertainties of the measurement. The data are compared with calculations using the AMPT model, which predicts a different pT and η dependence than observed in the data. The results are sensitive to the parent particle v2 and composition of reconstructed muon tracks, where the contribution from heavy flavour decays is expected to dominate at pT>2 GeV/c.

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 991 contributors for this article] (2016). Multipion Bose-Einstein correlations in pp,p -Pb, and Pb-Pb collisions at energies available at the CERN Large Hadron Collider. Physical Review C. Nuclear Physics. ISSN 0556-2813. 93(5). doi: 10.1103/PhysRevC.93.054908. Full text in Research Archive Show summary

  Three- and four-pionBose-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-pionmeasurements. 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.

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 52 contributors for this article] (2016). Event-by-Event Identified Particle Ratio Fluctuations in Pb–Pb Collisions with ALICE using the Identity Method. Nuclear Physics A. ISSN 0375-9474. 956, p. 870–873. doi: 10.1016/j.nuclphysa.2016.03.043. Full text in Research Archive
• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2016). Inclusive J/ψ and ψ(2S) production in p–Pb collisions with ALICE at the LHC. Nuclear Physics A. ISSN 0375-9474. 956, p. 689–692. doi: 10.1016/j.nuclphysa.2016.02.037. Full text in Research Archive
• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2016). Jet shapes in pp and Pb–Pb collisions at ALICE. Nuclear Physics A. ISSN 0375-9474. 956, p. 593–596. doi: 10.1016/j.nuclphysa.2016.02.060. Full text in Research Archive Show summary

  The aim of this work is to explore possible medium modifications to the substructure of inclusive charged jets in Pb-Pb relative to proton-proton collisions by measuring a set of jet shapes. The set of shapes includes the radial moment, g, and the momentum dispersion pTD. They provide complementary information on the fragmentation and can help to discriminate between two different scenarios: intra-jet broadening or collimation as a result of jet quenching. The shapes are measured in Pb–Pb collisions at √sNN = 2.76 TeV with a constituent cutoff of 0.15 GeV/c and jet resolution R = 0.2. New techniques for background subtraction are applied and a two-dimensional unfolding is performed to correct the shapes to particle level. The corrected jet shapes for jet pT 40 ≤ pT,jet ≤ 60 GeV/c are presented and discussed. The observed jet shape modifications suggest that the in-medium fragmentation is harder and more collimated than vacuum fragmentation as obtained by a PYTHIA calculation. The PYTHIA calculation is validated with proton-proton data at 7 TeV.

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 50 contributors for this article] (2016). Heavy-flavor correlations and multiplicity dependence in pp and p–Pb collisions with ALICE. Nuclear Physics A. ISSN 0375-9474. 956, p. 479–500. doi: 10.1016/j.nuclphysa.2016.02.057. Full text in Research Archive
• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 50 contributors for this article] (2016). Overview of recent ALICE results. Nuclear Physics A. ISSN 0375-9474. 956, p. 11–18. doi: 10.1016/j.nuclphysa.2016.02.038. Full text in Research Archive Show summary

  The ALICE experiment explores the properties of strongly interacting QCD matter at extremely high temperatures created in Pb-Pb collisions at LHC and provides further insight into small-system physics in (high-multiplicity) pp and p-Pb collisions. The ALICE collaboration presented 27 parallel talks, 50 posters, and 1 flash talk at Quark Matter 2015 and covered various topics including collective dynamics, correlations and fluctuations, heavy flavors, quarkonia, jets and high pT hadrons, electromagnetic probes, small system physics, and the upgrade program. This paper highlights some of the selected results.

• Adam, J.; Adamová, D.; Aggarwal, M.M.; Rinella, Rinella Aglieri; Agnello, M. & Agrawal, N. [Show all 982 contributors for this article] (2016). Centrality evolution of the charged-particle pseudorapidity density over a broad pseudorapidity range in Pb-Pb collisions at √sNN=2.76 TeV. Physics Letters B. ISSN 0370-2693. 754, p. 373–385. doi: 10.1016/j.physletb.2015.12.082. Full text in Research Archive
• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2016). Azimuthal anisotropy of charged jet production in √sNN=2.76 TeV Pb-Pb collisions. Physics Letters B. ISSN 0370-2693. 753, p. 511–525. doi: 10.1016/j.physletb.2015.12.047. Full text in Research Archive Show summary

  We present measurements of the azimuthal dependence of charged jet production in central and semi-central √sNN=2.76TeVPb–Pb collisions with respect to the second harmonic event plane, quantified as vchjet2. Jet finding is performed employing the anti-kTalgorithm with a resolution parameter R =0.2using charged tracks from the ALICE tracking system. The contribution of the azimuthal anisotropy of the underlying event is taken into account event-by-event. The remaining (statistical) region-to-region fluctuations are removed on an ensemble basis by unfolding the jet spectra for different event plane orientations independently. Significant non-zero vchjet2is observed in semi-central collisions (30–50% centrality) for 20

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2016). Charge-dependent flow and the search for the chiral magnetic wave in Pb-Pb collisions at √sNN =2.76 TeV. Physical Review C. Nuclear Physics. ISSN 0556-2813. 93:044903(4). doi: 10.1103/PhysRevC.93.044903. Full text in Research Archive Show summary

  We report on measurements of a charge-dependent flow using a novel three-particle correlator with ALICE in Pb-Pb collisions at the CERN Large Hadron Collider (LHC), and discuss the implications for observation of local parity violation and the chiral magnetic wave (CMW) in heavy-ion collisions. Charge-dependent flow is reported for different collision centralities as a function of the event charge asymmetry. While our results are in qualitative agreement with expectations based on the CMW, the nonzero signal observed in higher harmonics correlations indicates a possible significant background contribution. We also present results on a differential correlator, where the flow of positive and negative charges is reported as a function of the mean charge of the particles and their pseudorapidity separation. We argue that this differential correlator is better suited to distinguish the differences in positive and negative charges expected due to the CMW and the background effects, such as local charge conservation coupled with strong radial and anisotropic flow.

• Adam, Jaroslav; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo; Agrawal, Nikita & Ahammed, Zubayer [Show all 51 contributors for this article] (2016). Charged-Particle Multiplicity Distributions over a Wide Pseudorapidity Range in Proton–Proton Collisions with ALICE. Nuclear Physics A. ISSN 0375-9474. 956, p. 529–532. doi: 10.1016/j.nuclphysa.2016.01.025. Full text in Research Archive
• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2016). Azimuthal anisotropy of charged jet production in sNN=2.76 TeV Pb–Pb collisions. Nuclear Physics A. ISSN 0375-9474. 956, p. 629–632. doi: 10.1016/j.nuclphysa.2016.03.006. Full text in Research Archive
• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2016). Measurement of neutral mesons in pp and Pb–Pb collisions at mid-rapidity with ALICE. Nuclear Physics A. ISSN 0375-9474. 956, p. 645–648. doi: 10.1016/j.nuclphysa.2016.01.019. Full text in Research Archive
• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2016). Particle identification in ALICE: a Bayesian approach. The European Physical Journal Plus. 131:168(5). doi: 10.1140/epjp/i2016-16168-5. Full text in Research Archive Show summary

  We present a Bayesian approach to particle identification (PID) within the ALICE experiment. The aim is to more effectively combine the particle identification capabilities of its various detectors. After a brief explanation of the adopted methodology and formalism, the performance of the Bayesian PID approach for charged pions, kaons and protons in the central barrel of ALICE is studied. PID is performed via measurements of specific energy loss (dE/dx) and time of flight. PID efficiencies and misidentification probabilities are extracted and compared with Monte Carlo simulations using high-purity samples of identified particles in the decay channels K^0_S→π^−π^+ , ϕ→K^−K^+ , and Λ→pπ^− in p-Pb collisions at √sNN=5.02 TeV. In order to thoroughly assess the validity of the Bayesian approach, this methodology was used to obtain corrected p_T spectra of pions, kaons, protons, and D^0 mesons in pp collisions at √s=7 TeV. In all cases, the results using Bayesian PID were found to be consistent with previous measurements performed by ALICE using a standard PID approach. For the measurement of D^0→K^−π^+ , it was found that a Bayesian PID approach gave a higher signal-to-background ratio and a similar or larger statistical significance when compared with standard PID selections, despite a reduced identification efficiency. Finally, we present an exploratory study of the measurement of Λ^+_c→pK^−π^+ in pp collisions at √s=7 TeV, using the Bayesian approach for the identification of its decay products.

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2016). Multiplicity dependence of charged pion, kaon, and (anti)proton production at large transverse momentum in p–Pb collisions at √sNN=5.02 TeV. Physics Letters B. ISSN 0370-2693. 760, p. 720–735. doi: 10.1016/j.physletb.2016.07.050. Full text in Research Archive
• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 50 contributors for this article] (2016). Anisotropic flow of charged particles in Pb-Pb collisions at √sNN =5.02 TeV. Physical Review Letters. ISSN 0031-9007. 116(13). doi: 10.1103/PhysRevLett.116.132302. Full text in Research Archive
• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2016). Centrality dependence of ψ(2S) suppression in p-Pb collisions at √sNN= 5.02 TeV. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 2016(2016:50). doi: 10.1007/JHEP06(2016)050. Full text in Research Archive Show summary

  The inclusive production of the (2S) charmonium state was studied as a function of centrality in p-Pb collisions at the nucleon-nucleon center of mass energy √sNN = 5.02TeV at the CERN LHC. The measurement was performed with the ALICE detector in the center of mass rapidity ranges -4.46 < ycms < 2.96 and 2.03 < ycms < 3.53, down to zero transverse momentum, by reconstructing the (2S) decay to a muon pair. The (2S) production cross section _ (2S) is presented as a function of the collision centrality, which is estimated through the energy deposited in forward rapidity calorimeters. The relative strength of nuclear effects on the (2S) and on the corresponding 1S charmonium state J/ is then studied by means of the double ratio of cross sections [ _ (2S) =_ J = ] pPb = [ _ (2S) =_ J = ] pp between p-Pb and pp collisions, and by the values of the nuclear modification factors for the two charmonium states. The results show a large suppression of (2S) production relative to the J/ at backward (negative) rapidity, corresponding to the ight direction of the Pb-nucleus, while at forward (positive) rapidity the suppressions of the two states are comparable. Finally, comparisons to results from lower energy experiments and to available theoretical models are presented.

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Agnello, Michelangelo; Agrawal, Nikita & Ahammed, Zubayer [Show all 51 contributors for this article] (2016). Differential studies of inclusive J/ψ and ψ(2S) production at forward rapidity in Pb-Pb collisions at √sNN = 2.76 TeV. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 2016(5). doi: 10.1007/JHEP05(2016)179. Full text in Research Archive Show summary

  The production of J/ and (2S) was studied with the ALICE detector in Pb-Pb collisions at the LHC. The measurement was performed at forward rapidity (2:5 < y < 4) down to zero transverse momentum (pt) in the dimuon decay channel. Inclusive J/ yields were extracted in di erent centrality classes and the centrality dependence of the average pt is presented. The J/ suppression, quanti ed with the nuclear modi cation factor (RAA), was measured as a function of centrality, transverse momentum and rapidity. Comparisons with similar measurements at lower collision energy and theoretical models indicate that the J/ production is the result of an interplay between color screening and recombination mechanisms in a decon ned partonic medium, or at its hadronization. Results on the (2S) suppression are provided via the ratio of (2S) over J/ measured in pp and Pb-Pb collisions.

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2016). ϕ production at forward rapidity in pp, p–Pb and Pb–Pb collisions with ALICE. Nuclear Physics A. ISSN 0375-9474. 956, p. 453–456. doi: 10.1016/j.nuclphysa.2016.03.053. Full text in Research Archive
• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 52 contributors for this article] (2016). Upsilon production measurements in pp, p–Pb and Pb–Pb collisions with ALICE. Nuclear Physics A. ISSN 0375-9474. 956, p. 709–712. doi: 10.1016/j.nuclphysa.2016.01.016. Full text in Research Archive
• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2016). Results from (anti-)(hyper-)nuclei production and searches for exotic bound states with ALICE at the LHC. Nuclear Physics A. ISSN 0375-9474. 956, p. 461–464. doi: 10.1016/j.nuclphysa.2016.01.066. Full text in Research Archive
• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2016). Measurements of heavy-flavour production in p–Pb collisions with ALICE. Nuclear Physics A. ISSN 0375-9474. 956, p. 493–496. doi: 10.1016/j.nuclphysa.2016.01.049. Full text in Research Archive
• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 972 contributors for this article] (2016). Search for weakly decaying Λn and ΛΛ exotic bound states in central Pb-Pb collisions at √sNN=2.76 TeV. Physics Letters B. ISSN 0370-2693. 752, p. 267–277. doi: 10.1016/j.physletb.2015.11.048. Full text in Research Archive Show summary

  We present results of a search for two hypothetical strange dibaryon states, i.e. the H-dibaryon and the possible Λn‾ bound state. The search is performed with the ALICE detector in central (0–10%) Pb–Pb collisions at sNN=2.76 TeV, by invariant mass analysis in the decay modes Λn‾→d‾π+ and H-dibaryon →Λpπ−. No evidence for these bound states is observed. Upper limits are determined at 99% confidence level for a wide range of lifetimes and for the full range of branching ratios. The results are compared to thermal, coalescence and hybrid UrQMD model expectations, which describe correctly the production of other loosely bound states, like the deuteron and the hypertriton.

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2016). Pseudorapidity and transverse-momentum distributions of charged particles in proton-proton collisions at √s = 13 TeV. Physics Letters B. ISSN 0370-2693. 753, p. 319–329. doi: 10.1016/j.physletb.2015.12.030. Full text in Research Archive
• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2016). Measurements of heavy-flavour nuclear modification factor and elliptic flow in Pb–Pb collisions at √sNN = 2.76 TeV with ALICE. Nuclear Physics A. ISSN 0375-9474. 956, p. 477–480. doi: 10.1016/j.nuclphysa.2016.03.044. Full text in Research Archive
• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2016). Low-Mass Dielectron Production in pp, p–Pb and Pb–Pb Collisions with ALICE. Nuclear Physics A. ISSN 0375-9474. 956, p. 433–436. doi: 10.1016/j.nuclphysa.2016.01.060. Full text in Research Archive
• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 981 contributors for this article] (2016). Measurement of Ds + production and nuclear modification factor in Pb-Pb collisions at √sNN = 2.76 TeV. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 2016:82(3). doi: 10.1007/JHEP03(2016)082. Full text in Research Archive Show summary

  The production of prompt D s + mesons was measured for the first time in collisions of heavy nuclei with the ALICE detector at the LHC. The analysis was performed on a data sample of Pb-Pb collisions at a centre-of-mass energy per nucleon pair, sNN−−−√ , of 2.76 TeV in two different centrality classes, namely 0–10% and 20–50%. D s + mesons and their antiparticles were reconstructed at mid-rapidity from their hadronic decay channel D s +  → ϕπ +, with ϕ → K−K+, in the transverse momentum intervals 4 < p T < 12GeV/c and 6 < p T < 12 GeV/c for the 0–10% and 20–50% centrality classes, respectively. The nuclear modification factor R AA was computed by comparing the p T-differential production yields in Pb-Pb collisions to those in proton-proton (pp) collisions at the same energy. This pp reference was obtained using the cross section measured at s√=7 TeV and scaled to s√=2.76 TeV. The R AA of D s + mesons was compared to that of non-strange D mesons in the 10% most central Pb-Pb collisions. At high p T (8 < p T < 12 GeV/c) a suppression of the D s + -meson yield by a factor of about three, compatible within uncertainties with that of non-strange D mesons, is observed. At lower p T (4 < p T < 8 GeV/c) the values of the D s + -meson R AA are larger than those of non-strange D mesons, although compatible within uncertainties. The production ratios D s + /D0 and D s + /D+ were also measured in Pb-Pb collisions and compared to their values in proton-proton collisions.

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 990 contributors for this article] (2016). Study of cosmic ray events with high muon multiplicity using the ALICE detector at the CERN Large Hadron Collider. Journal of Cosmology and Astroparticle Physics (JCAP). 2016(1). doi: 10.1088/1475-7516/2016/01/032. Full text in Research Archive Show summary

  ALICE is one of four large experiments at the CERN Large Hadron Collider near Geneva, specially designed to study particle production in ultra-relativistic heavy-ion collisions. Located 52 meters underground with 28 meters of overburden rock, it has also been used to detect muons produced by cosmic ray interactions in the upper atmosphere. In this paper, we present the multiplicity distribution of these atmospheric muons and its comparison with Monte Carlo simulations. This analysis exploits the large size and excellent tracking capability of the ALICE Time Projection Chamber. A special emphasis is given to the study of high multiplicity events containing more than 100 reconstructed muons and corresponding to a muon areal density __ > 5:9 m􀀀2. Similar events have been studied in previous underground experiments such as ALEPH and DELPHI at LEP. While these experiments were able to reproduce the measured muon multiplicity distribution with Monte Carlo simulations at low and intermediate multiplicities, their simulations failed to describe the frequency of the highest multiplicity events. In this work we show that the high multiplicity events observed in ALICE stem from primary cosmic rays with energies above 1016 eV and that the frequency of these events can be successfully described by assuming a heavy mass composition of primary cosmic rays in this energy range. The development of the resulting air showers was simulated using the latest version of QGSJET to model hadronic interactions. This observation places significant constraints on alternative, more exotic, production mechanisms for these events.

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2016). Transverse momentum dependence of D-meson production in Pb-Pb collisions at √sNN = 2.76 TeV. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 2016:81. doi: 10.1007/JHEP03(2016)081. Full text in Research Archive Show summary

  The production of prompt charmed mesons D0, D+ and D∗+, and their antiparticles, was measured with the ALICE detector in Pb-Pb collisions at the centre-of-mass energy per nucleon pair, sNN−−−√, of 2.76 TeV. The production yields for rapidity |y| < 0.5 are presented as a function of transverse momentum, p T, in the interval 1–36 GeV/c for the centrality class 0–10% and in the interval 1–16 GeV/c for the centrality class 30–50%. The nuclear modification factor R AA was computed using a proton-proton reference at s√=2.76 TeV, based on measurements at s√=7 TeV and on theoretical calculations. A maximum suppression by a factor of 5-6 with respect to binary-scaled pp yields is observed for the most central collisions at p T of about 10 GeV/c. A suppression by a factor of about 2-3 persists at the highest p T covered by the measurements. At low p T (1-3 GeV/c), the R AA has large uncertainties that span the range 0.35 (factor of about 3 suppression) to 1 (no suppression). In all p T intervals, the R AA is larger in the 30-50% centrality class compared to central collisions. The D-meson R AA is also compared with that of charged pions and, at large p T, charged hadrons, and with model calculations.

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2016). Pseudorapidity dependence of the anisotropic flow of charged particles in Pb–Pb collisions at √sNN = 2.76 TeV. Physics Letters B. ISSN 0370-2693. 762, p. 376–388. doi: 10.1016/j.physletb.2016.07.017. Full text in Research Archive Show summary

  We present measurements of the elliptic (v2), triangular (v3) and quadrangular (v4) anisotropic azimuthal flow over a wide range of pseudorapidities (−3.5 < η < 5). The measurements are performed with Pb–Pb collisions at √sNN = 2.76 TeVusing the ALICE detector at the Large Hadron Collider (LHC). The flow harmonics are obtained using two-and four-particle correlations from nine different centrality intervals covering central to peripheral collisions. We find that the shape of vn(η)is largely independent of centrality for the flow harmonics n = 2–4, however the higher harmonics fall off more steeply with increasing |η|. We assess the validity of extended longitudinal scaling of v2 by comparing to lower energy measurements, and find that the higher harmonic flow coefficients are proportional to the charged particle densities at larger pseudorapidities. Finally, we compare our measurements to both hydrodynamical and transport models, and find they both have challenges when it comes to describing our data.

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2016). D-meson production in p-Pb collisions at √sNN = 5.02 TeV and in pp collisions at √s = 7 TeV. Physical Review C. Nuclear Physics. ISSN 0556-2813. 94:054908(7), p. 1–31. doi: 10.1103/PhysRevC.94.054908. Full text in Research Archive Show summary

  Background: In the context of the investigation of the quark gluon plasma produced in heavy-ion collisions, hadrons containing heavy (charm or beauty) quarks play a special role for the characterization of the hot and dense medium created in the interaction. The measurement of the production of charm and beauty hadrons in proton–proton collisions, besides providing the necessary reference for the studies in heavy-ion reactions, constitutes an important test of perturbative quantum chromodynamics (pQCD) calculations. Heavy-flavor production in proton–nucleus collisions is sensitive to the various effects related to the presence of nuclei in the colliding system, commonly denoted cold-nuclear-matter effects. Most of these effects are expected to modify open-charm production at low transverse momenta (pT) and, so far, no measurement of D-meson production down to zero transverse momentum was available at mid-rapidity at the energies attained at the CERN Large Hadron Collider (LHC). Purpose: The measurements of the production cross sections of promptly produced charmed mesons in p-Pb collisions at the LHC down to pT = 0 and the comparison to the results from pp interactions are aimed at the assessment of cold-nuclear-matter effects on open-charm production, which is crucial for the interpretation of the results from Pb-Pb collisions. Methods: The prompt charmedmesonsD0,D+,D∗+, andD+s weremeasured at mid-rapidity in p-Pb collisions at a center-of-mass energy per nucleon pair √sNN = 5.02 TeV with the ALICE detector at the LHC.D mesons were reconstructed from their decays D0 → K−π+, D+ → K−π+π+, D∗+ → D0π+, D+s→ φπ+ → K−K+π+, and their charge conjugates, using an analysis method based on the selection of decay topologies displaced from the interaction vertex. In addition, the prompt D0 √ production cross section was measured in pp collisions at s = 7 TeV and p-Pb collisions at √sNN = 5.02 TeV down to pT = 0 using an analysis technique that is based on the estimation and subtraction of the combinatorial background, without reconstruction of theD0 decay vertex. Results: The production cross section in pp collisions is described within uncertainties by different implementations of pQCD calculations down to pT = 0. This allowed also a determination of the total c ¯ c production cross section in pp collisions, which is more precise than previous ALICE measurements because it is not affected by uncertainties owing to the extrapolation to pT = 0. The nuclear modification factor RpPb(pT), defined as the ratio of the pT-differential D meson cross section in p-Pb collisions and that in pp collisions scaled by the mass number of the Pb nucleus, was calculated for the four D-meson species and found to be compatible with unity within uncertainties. The results are compared to theoretical calculations that include cold-nuclear-matter effects and to transport model calculations incorporating the interactions of charm quarks with an expanding deconfined medium. Conclusions: These measurements add experimental evidence that the modification of the D-meson transverse momentum distributions observed in Pb–Pb collisions with respect to pp interactions is due to strong final-state effects induced by the interactions of the charm quarks with the hot and dense partonic medium created in ultrarelativistic heavy-ion collisions. The current precision of the measurement does not allow us to draw conclusions on the role of the different cold-nuclear-matter effects and on the possible presence of additional hot-medium effects in p-Pb collisions. However, the analysis technique without decay-vertex reconstruction, applied on future larger data samples, should provide access to the physics-rich range down to pT = 0.

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2016). Jet-like correlations with neutral pion triggers in pp and central Pb–Pb collisions at 2.76 TeV. Physics Letters B. ISSN 0370-2693. 763, p. 238–250. doi: 10.1016/j.physletb.2016.10.048. Full text in Research Archive Show summary

  We present measurements of two-particle correlations with neutral pion trigger particles of transverse momenta \(8 < p_{\mathrm{T}}^{\rm trig} < 16 \mathrm{GeV}/c\) and associated charged particles of \(0.5 < p_{\mathrm{T}}^{\rm assoc} < 10 \mathrm{GeV}/c\) versus the azimuthal angle difference \(\Delta\varphi\) at midrapidity in pp and central Pb-Pb collisions at \(\sqrt{s_{\mathrm{NN}}}=2.76\) TeV with ALICE. The new measurements exploit associated charged hadrons down to \(0.5 \mathrm{GeV}/c\), which significantly extends our previous measurement that only used charged hadrons above \(3 \mathrm{GeV}/c\), After subtracting the contributions of the flow background, \(v_2\) to \(v_5\), the per-trigger yields are extracted for \(|\Delta\varphi|<0.7\) on the near and for \(|\Delta\varphi-\pi| < 1.1\) on the away side. The ratio of per-trigger yields in Pb--Pb to those in pp collisions, \(I_{\mathrm{AA}}\), is measured on the near and away side for the \(0\)--\(10\)% most central Pb--Pb collisions. On the away side, the per-trigger yields in Pb--Pb are strongly suppressed to the level of \(I_{\mathrm{AA}} \approx 0.6\) for \(p_{\mathrm{T}}^{\rm assoc} > 3 \mathrm{GeV}/c\), while with decreasing momenta an enhancement develops reaching about \(5\) at low \(p_{\mathrm{T}}^{\rm assoc}\), On the near side, an enhancement of \(I_{\mathrm{AA}}\) between \(1.2\) at the highest to \(1.8\) at the lowest \(p_{\mathrm{T}}^{\rm assoc}\) is observed. The data are compared to parton-energy-loss predictions of the JEWEL and AMPT event generators, as well as to a perturbative QCD calculation with medium-modified fragmentation functions. All calculations qualitatively describe the away-side suppression at high \(p_{\mathrm{T}}^{\rm assoc}\), Only AMPT captures the enhancement at low \(p_{\mathrm{T}}^{\rm assoc}\), both on the near and away side. However, it also underpredicts \(I_{\mathrm{AA}}\) above \(5\) GeV/\(c\), in particular on the near-side.

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2016). Measurement of electrons from heavy-flavour hadron decays in p-Pb collisions at √sNN = 5.02 TeV. Physics Letters B. ISSN 0370-2693. 754, p. 81–93. doi: 10.1016/j.physletb.2015.12.067. Full text in Research Archive
• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2016). Multiplicity and transverse momentum evolution of charge-dependent correlations in pp, p-Pb, and Pb-Pb collisions at the LHC. European Physical Journal C. ISSN 1434-6044. 76:86(2), p. 1–24. doi: 10.1140/epjc/s10052-016-3915-1. Full text in Research Archive Show summary

  We report on two-particle charge-dependent correlations in pp, p-Pb, and Pb-Pb collisions as a function of the pseudorapidity and azimuthal angle difference, \(\mathrm{\Delta}\eta\) and \(\mathrm{\Delta}\varphi\) respectively. These correlations are studied using the balance function that probes the charge creation time and the development of collectivity in the produced system. The dependence of the balance function on the event multiplicity as well as on the trigger and associated particle transverse momentum \(p_{\mathrm{T}}\) in pp, p-Pb, and Pb-Pb collisions at \(\sqrt{s_{\mathrm{NN}}} = 7\). 5.02, and 2.76 TeV, respectively, are presented. In the low transverse momentum region, for \(0.2 < p_{\mathrm{T}} < 2.0\) GeV/\).\). the balance function becomes narrower in both \(\mathrm{\Delta}\eta\) and \(\mathrm{\Delta}\varphi\) directions in all three systems for events with higher multiplicity. The experimental findings favor models that either incorporate some collective behavior (e.g. AMPT) or different mechanisms that lead to effects that resemble collective behavior (e.g. PYTHIA8 with color reconnection). For higher values of transverse momenta the balance function becomes even narrower but exhibits no multiplicity dependence, indicating that the observed narrowing with increasing multiplicity at low \(p_{\mathrm{T}}\) is a feature of bulk particle production.

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 987 contributors for this article] (2016). Event-shape engineering for inclusive spectra and elliptic flow in Pb-Pb collisions at √sNN =2.76 TeV. Physical Review C. Nuclear Physics. ISSN 0556-2813. 93(3). doi: 10.1103/PhysRevC.93.034916. Full text in Research Archive Show summary

  We report on results obtained with the event-shape engineering technique applied to Pb-Pb collisions at √sNN=2.76 TeV. By selecting events in the same centrality interval, but with very different average flow, different initial-state conditions can be studied. We find the effect of the event-shape selection on the elliptic flow coefficient v2 to be almost independent of transverse momentum pT, which is as expected if this effect is attributable to fluctuations in the initial geometry of the system. Charged-hadron, -pion, -kaon, and -proton transverse momentum distributions are found to be harder in events with higher-than-average elliptic flow, indicating an interplay between radial and elliptic flow.

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2016). Production of light nuclei and anti-nuclei in pp and Pb-Pb collisions at energies available at the CERN Large Hadron Collider. Physical Review C. Nuclear Physics. ISSN 0556-2813. 93(2). doi: 10.1103/PhysRevC.93.024917. Full text in Research Archive Show summary

  The production of (anti-)deuteron and (anti-)\)^{3}\)He nuclei in Pb-Pb collisions at \(\sqrt{s_{\rm NN}}\) = 2.76 TeV has been studied using the ALICE detector at the LHC. The spectra exhibit a significant hardening with increasing centrality. Combined blast-wave fits of several particles support the interpretation that this behavior is caused by an increase of radial flow. The integrated particle yields are discussed in the context of coalescence and thermal-statistical model expectations. The particle ratios, \(^3\)He/d and \(^3\)He/p, in Pb-Pb collisions are found to be in agreement with a common chemical freeze-out temperature of \(T_{\rm chem} \approx 156\) MeV. These ratios do not vary with centrality which is in agreement with the thermal-statistical model. In a coalescence approach, it excludes models in which nucleus production is proportional to the particle multiplicity and favors those in which it is proportional to the particle density instead. In addition, the observation of 31 anti-tritons in Pb-Pb collisions is reported. For comparison, the deuteron spectrum in pp collisions at \(\sqrt{s} = 7\) TeV is also presented. While the p/\(pi)\) ratio is similar in pp and Pb-Pb collisions, the d/p ratio in pp collisions is found to be lower by a factor of 2.2 than in Pb-Pb collisions.

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 992 contributors for this article] (2016). Production of K∗(892)0 and ϕ (1020) in p–Pb collisions at √sNN = 5.02 TeV. European Physical Journal C. ISSN 1434-6044. 76:245(5). doi: 10.1140/epjc/s10052-016-4088-7. Full text in Research Archive
• Adamová, Dagmar; Adam, Jaroslav; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2016). Multi-strange baryon production in pPb collisions at √sNN=5.02 TeV. Physics Letters B. ISSN 0370-2693. 758, p. 389–401. doi: 10.1016/j.physletb.2016.05.027. Full text in Research Archive
• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 53 contributors for this article] (2016). Elliptic flow of electrons from heavy-flavour hadron decays at mid-rapidity in Pb-Pb collisions at √sNN=2.76 TeV. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 2016:28(9). doi: 10.1007/JHEP09(2016)028. Full text in Research Archive Show summary

  The elliptic ow of electrons from heavy-avour hadron decays at mid-rapidity (|y| < 0.7) is measured in Pb-Pb collisions at √sNN = 2:76TeV with ALICE at the LHC. The particle azimuthal distribution with respect to the reaction plane can be parametrized with a Fourier expansion, where the second coefficient (v2) represents the elliptic flow. The v2 coefficient of inclusive electrons is measured in three centrality classes (0-10%, 10-20% and 20-40%) with the event plane and the scalar product methods in the transverse momentum (pT) intervals 0.5-13 GeV/c and 0.5-8 GeV/c, respectively. After subtracting the background, mainly from photon conversions and Dalitz decays of neutral mesons, a positive v2 of electrons from heavy-avour hadron decays is observed in all centrality classes, with a maximum signicance of 5:9_ in the interval 2 < pT < 2.5 GeV/c in semicentral collisions (20-40%). The value of v2 decreases towards more central collisions at low and intermediate pT (0.5 < pT < 3 GeV/c). The v2 of electrons from heavy-flavour hadron decays at mid-rapidity is found to be similar to the one of muons from heavy-flavour hadron decays at forward rapidity (2.5 < y < 4). The results are described within uncertainties by model calculations including substantial elastic interactions of heavy quarks with an expanding strongly-interacting medium.

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2016). Direct photon measurement in Pb-Pb collisions at √sNN = 2.76 TeV with ALICE. Nuclear Physics A. ISSN 0375-9474. 956, p. 421–424. doi: 10.1016/j.nuclphysa.2016.03.052. Full text in Research Archive
• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2016). 3ΛH and -3Λ-H production in Pb-Pb collisions at √sNN=2.76 TeV. Physics Letters B. ISSN 0370-2693. 754, p. 360–372. doi: 10.1016/j.physletb.2016.01.040. Full text in Research Archive Show summary

  The production of the hypertriton nuclei 3_Hand 3¯_Hhas been measured for the first time in Pb–Pbcollisions at √sNN=2.76TeVwith the ALICE experiment at LHC. The pT-integrated 3_Hyield in one unity of rapidity, dN/dy ×B.R. _3_H→3He,π− _=(3.86±0.77(stat.)±0.68(syst.))×10−5in the 0–10%most central collisions, is consistent with the predictions from a statistical thermal model using the same temperature as for the light hadrons. The coalescence parameter B3shows a dependence on the transverse momentum, similar to the B2of deuterons and the B3of 3He nuclei. The ratio of yields S3=3_H/(3He×_/p)was measured to be S3=0.60 ±0.13(stat.) ±0.21(syst.)in 0–10%centrality events; this value is compared to different theoretical models. The measured S3is compatible with hermal model predictions. The measured 3_Hlifetime, τ=181+54−39(stat.) ±33(syst.) psis in agreement within 1σwith the world average value.

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 986 contributors for this article] (2016). Centrality dependence of the nuclear modification factor of charged pions, kaons, and protons in Pb-Pb collisions at √sNN =2.76 TeV. Physical Review C. Nuclear Physics. ISSN 0556-2813. 93(3). doi: 10.1103/PhysRevC.93.034913. Full text in Research Archive Show summary

  Transverse momentum (pT) spectra of pions, kaons, and protons up to pT=20GeV/c have been measured in Pb-Pb collisions at √sNN=2.76TeV using the ALICE detector for six different centrality classes covering 0%–80%. The proton-to-pion and the kaon-to-pion ratios both show a distinct peak at pT≈3GeV/c in central Pb-Pb collisions that decreases for more peripheral collisions. For pT>10GeV/c, the nuclear modification factor is found to be the same for all three particle species in each centrality interval within systematic uncertainties of 10%–20%. This suggests there is no direct interplay between the energy loss in the medium and the particle species composition in the hard core of the quenched jet. For pT<10GeV/c, the data provide important constraints for models aimed at describing the transition from soft to hard physics.

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 981 contributors for this article] (2016). Inclusive quarkonium production at forward rapidity in pp collisions at √s = 8 TeV. European Physical Journal C. ISSN 1434-6044. 76(4). doi: 10.1140/epjc/s10052-016-3987-y. Full text in Research Archive
• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 52 contributors for this article] (2016). Strangeness production as a function of charged particle multiplicity in proton-proton collisions. Nuclear Physics A. ISSN 0375-9474. 956, p. 777–780. doi: 10.1016/j.nuclphysa.2016.03.005. Full text in Research Archive
• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 52 contributors for this article] (2016). Light flavor results in p-Pb collisions with ALICE. Nuclear Physics A. ISSN 0375-9474. 956, p. 757–760. doi: 10.1016/j.nuclphysa.2016.02.055. Full text in Research Archive
• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 986 contributors for this article] (2016). Centrality dependence of pion freeze-out radii in Pb-Pb collisions at √sNN =2.76 TeV. Physical Review C. Nuclear Physics. ISSN 0556-2813. 93(2). doi: 10.1103/PhysRevC.93.024905. Full text in Research Archive Show summary

  We report on the measurement of freeze-out radii for pairs of identical-charge pions measured in Pb-Pb collisions at √sNN = 2.76 TeV as a function of collision centrality and the average transverse momentum of the pair kT. Three-dimensional sizes of the system (femtoscopic radii), as well as direction-averaged onedimensional radii are extracted. The radii decrease with kT, following a power-law behavior. This is qualitatively consistent with expectations from a collectively expanding system, produced in hydrodynamic calculations. The radii also scale linearly with _dNch/dη_1/3. This behavior is compared to world data on femtoscopic radii in heavy-ion collisions. While the dependence is qualitatively similar to results at smaller √sNN, a decrease in the ratio Rout/Rside is seen, which is in qualitative agreement with a specific prediction from hydrodynamic models: a change from inside-out to outside-in freeze-out configuration. The results provide further evidence for the production of a collective, strongly coupled system in heavy-ion collisions at the CERN Large Hadron Collider.

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2016). Correlated event-by-event Fluctuations of Flow Harmonics in Pb-Pb collisions at √sNN =2.76 TeV. Physical Review Letters. ISSN 0031-9007. 117:182301(8), p. 1–14. doi: 10.1103/PhysRevLett.117.182301. Full text in Research Archive Show summary

  We report the measurements of correlations between event-by-event fluctuations of amplitudes of anisotropic flow harmonics in nucleus-nucleus collisions, obtained for the first time using a new analysis method based on multiparticle cumulants in mixed harmonics. This novel method is robust against systematic biases originating from nonflow effects and by construction any dependence on symmetry planes is eliminated. We demonstrate that correlations of flow harmonics exhibit a better sensitivity to medium properties than the individual flow harmonics. The new measurements are performed in Pb-Pb collisions at the center-of-mass energy per nucleon pair of √snn = 2.76 TeV by the ALICE experiment at the Large Hadron Collider. The centrality dependence of correlation between event-by-event fluctuations of the elliptic v2 and quadrangular v4 flow harmonics, as well as of anticorrelation between v2 and triangular v3 flow harmonics are presented. The results cover two different regimes of the initial state configurations: geometry dominated (in midcentral collisions) and fluctuation dominated (in the most central collisions). Comparisons are made to predictions from Monte Carlo Glauber, viscous hydrodynamics, AMPT, and HIJING models. Together with the existing measurements of the 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.

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2016). Measurement of D-meson production versus multiplicity in p-Pb collisions at √sNN=5.02 TeV. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 2016:78(8). doi: 10.1007/JHEP08(2016)078. Full text in Research Archive Show summary

  The measurement of prompt D-meson production as a function of multiplicity in p-Pb collisions at √sNN = 5.02 TeV with the ALICE detector at the LHC is reported. D0, D+ and D_+ mesons are reconstructed via their hadronic decay channels in the centre-of-mass rapidity range -0.96 < ycms < 0.04 and transverse momentum interval 1 < pT < 24 GeV= c. The multiplicity dependence of D-meson production is examined by either comparing yields in p-Pb collisions in different event classes, selected based on the multiplicity of produced particles or zero-degree energy, with those in pp collisions, scaled by the number of binary nucleon-nucleon collisions (nuclear modification factor); as well as by evaluating the per-event yields in p{Pb collisions in different multiplicity intervals normalised to the multiplicity-integrated ones (relative yields). The nuclear modification factors for D0, D+ and D_+ are consistent with one another. The D-meson nuclear modifcation factors as a function of the zero-degree energy are consistent with unity within uncertainties in the measured pT regions and event classes. The relative D-meson yields, calculated in various pT intervals, increase as a function of the charged-particle multiplicity. The results are compared with the quivalent pp measurements at √s = 7 TeV as well as with EPOS 3 calculations.

• Abelev, Betty; Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri & Agnello, Michelangelo [Show all 51 contributors for this article] (2015). Production of Σ(1385)± and Ξ(1530)0 in proton–proton collisions at √s = 7 TeV. European Physical Journal C. ISSN 1434-6044. 75(1), p. 1–19. doi: 10.1140/epjc/s10052-014-3191-x. Full text in Research Archive Show summary

  The production of the strange and double-strange baryon resonances ((1385)±, Ξ(1530)0) has been measured at mid-rapidity (|y|< 0.5) in proton–proton collisions at √s = 7 TeV with the ALICE detector at the LHC. Transverse momentum spectra for inelastic collisions are compared to QCD-inspired models, which in general underpredict the data. A search for the φ(1860) pentaquark, decaying in the Ξπ channel, has been carried out but no evidence is seen.

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 52 contributors for this article] (2015). Centrality dependence of inclusive J/ψ production in p-Pb collisions at √sNN = 5.02 TeV. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 2015:127(11), p. 1–33. doi: 10.1007/JHEP11(2015)127. Full text in Research Archive Show summary

  We present a measurement of inclusive J/ψ production in p-Pb collisions at sNN−−−√=5.02 TeV as a function of the centrality of the collision, as estimated from the energy deposited in the Zero Degree Calorimeters. The measurement is performed with the ALICE detector down to zero transverse momentum, p T, in the backward (−4.46 < y cms < −2.96) and forward (2.03 < y cms < 3.53) rapidity intervals in the dimuon decay channel and in the mid-rapidity region (−1.37 < y cms < 0.43) in the dielectron decay channel. The backward and forward rapidity intervals correspond to the Pb-going and p-going direction, respectively. The p T-differential J/ψ production cross section at backward and forward rapidity is measured for several centrality classes, together with the corresponding average p T and p T2 values. The nuclear modification factor is presented as a function of centrality for the three rapidity intervals, and as a function of p T for several centrality classes at backward and forward rapidity. At mid- and forward rapidity, the J/ψ yield is suppressed up to 40% compared to that in pp interactions scaled by the number of binary collisions. The degree of suppression increases towards central p-Pb collisions at forward rapidity, and with decreasing p T of the J/ψ. At backward rapidity, the nuclear modification factor is compatible with unity within the total uncertainties, with an increasing trend from peripheral to central p-Pb collisions.

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2015). Coherent ρ 0 photoproduction in ultra-peripheral Pb-Pb collisions at √sNN=2.76 TeV. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 2015:95(9). doi: 10.1007/JHEP09(2015)095. Full text in Research Archive Show summary

  We report the first measurement at the LHC of coherent photoproduction of 0 mesons in ultra-peripheral Pb-Pb collisions. The invariant mass and transverse momentum distributions for 0 production are studied in the + − decay channel at mid-rapidity. The production cross section in the rapidity range |y| < 0.5 is found to be d /dy = 425 ± 10 (stat.) +42 −50 (sys.) mb. Coherent 0 production is studied with and without requirement of nuclear breakup, and the fractional yields for various breakup scenarios are presented. The results are compared with those from lower energies and with model predictions

• Abelev, Betty; Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Agnello, Michelangelo & Agostinelli, Andrea [Show all 51 contributors for this article] (2015). Measurement of electrons from semileptonic heavy-flavor hadron decays in pp collisions at s =2.76TeV. Physical Review D. ISSN 1550-7998. 91(1). doi: 10.1103/PhysRevD.91.012001. Full text in Research Archive Show summary

  The pT-differential production cross section of electrons from semileptonic decays of heavy-flavor hadrons has been measured at midrapidity in proton-proton collisions at s√=2.76  TeV in the transverse momentum range 0.5<pT<12  GeV/c with the ALICE detector at the LHC. The analysis was performed using minimum bias events and events triggered by the electromagnetic calorimeter. Predictions from perturbative QCD calculations agree with the data within the theoretical and experimental uncertainties.

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2015). Centrality dependence of high-pT D meson suppression in Pb-Pb collisions at √sNN = 2.76 TeV. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 2015:205(11), p. 1–24. doi: 10.1007/JHEP11(2015)205. Full text in Research Archive Show summary

  The nuclear modi cation factor, RAA, of the prompt charmed mesons D0, D+ and D +, and their antiparticles, was measured with the ALICE detector in Pb-Pb collisions at a centre-of-mass energy p sNN = 2:76 TeV in two transverse momentum intervals, 5 < pT < 8 GeV=c and 8 < pT < 16 GeV=c, and in six collision centrality classes. The RAA shows a maximum suppression of a factor of 5{6 in the 10% most central collisions. The suppression and its centrality dependence are compatible within uncertainties with those of charged pions. A comparison with the RAA of non-prompt J= from B meson decays, measured by the CMS Collaboration, hints at a larger suppression of D mesons in the most central collisions.

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2015). Coherent ψ(2S) photo-production in ultra-peripheral PbPb collisions at √sNN=2.76 TeV. Physics Letters B. ISSN 0370-2693. 751, p. 358–370. doi: 10.1016/j.physletb.2015.10.040. Full text in Research Archive
• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 50 contributors for this article] (2015). Inclusive, prompt and non-prompt J/ψ production at mid-rapidity in Pb-Pb collisions at √sNN = 2.76 TeV. Journal of High Energy Physics (JHEP). ISSN 1126-6708. 2015:51(7). doi: 10.1007/JHEP07(2015)051. Full text in Research Archive Show summary

  The transverse momentum (p T) dependence of the nuclear modification factor R AA and the centrality dependence of the average transverse momentum 〈p T〉 for inclusive J/ψ have been measured with ALICE for Pb-Pb collisions at sNN−−−√=2.76 TeV in the e+e− decay channel at mid-rapidity (|y| < 0.8). The 〈p T〉 is significantly smaller than the one observed for pp collisions at the same centre-of-mass energy. Consistently, an increase of R AA is observed towards low p T. These observations might be indicative of a sizable contribution of charm quark coalescence to the J/ψ production. Additionally, the fraction of non-prompt J/ψ from beauty hadron decays, f B, has been determined in the region 1.5 < p T < 10 GeV/c in three centrality intervals. No significant centrality dependence of f B is observed. Finally, the R AA of non-prompt J/ψ is discussed and compared with model predictions. The nuclear modification in the region 4.5 < p T < 10 GeV/c is found to be stronger than predicted by most models.

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 52 contributors for this article] (2015). Measurement of pion, kaon and proton production in proton–proton collisions at √s = 7 TeV. European Physical Journal C. ISSN 1434-6044. 75(5). doi: 10.1140/epjc/s10052-015-3422-9. Full text in Research Archive Show summary

  The measurement of primary π±, K±, p and p¯¯¯ production at mid-rapidity (|y|< 0.5) in proton–proton collisions at s√ = 7 TeV performed with a large ion collider experiment at the large hadron collider (LHC) is reported. Particle identification is performed using the specific ionisation energy-loss and time-of-flight information, the ring-imaging Cherenkov technique and the kink-topology identification of weak decays of charged kaons. Transverse momentum spectra are measured from 0.1 up to 3 GeV/c for pions, from 0.2 up to 6 GeV/c for kaons and from 0.3 up to 6 GeV/c for protons. The measured spectra and particle ratios are compared with quantum chromodynamics-inspired models, tuned to reproduce also the earlier measurements performed at the LHC. Furthermore, the integrated particle yields and ratios as well as the average transverse momenta are compared with results at lower collision energies.

• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2015). Measurement of dijet kT in p-Pb collisions at √sNN=5.02 TeV. Physics Letters B. ISSN 0370-2693. 746, p. 385–395. doi: 10.1016/j.physletb.2015.05.033. Full text in Research Archive Show summary

  A measurement of dijet correlations in p–Pb collisions at View the MathML source with the ALICE detector is presented. Jets are reconstructed from charged particles measured in the central tracking detectors and neutral energy deposited in the electromagnetic calorimeter. The transverse momentum of the full jet (clustered from charged and neutral constituents) and charged jet (clustered from charged particles only) is corrected event-by-event for the contribution of the underlying event, while corrections for underlying event fluctuations and finite detector resolution are applied on an inclusive basis. A projection of the dijet transverse momentum, View the MathML source with Δφdijet the azimuthal angle between a full and charged jet and View the MathML source the transverse momentum of the full jet, is used to study nuclear matter effects in p–Pb collisions. This observable is sensitive to the acoplanarity of dijet production and its potential modification in p–Pb collisions with respect to pp collisions. Measurements of the dijet kTy as a function of the transverse momentum of the full and recoil charged jet, and the event multiplicity are presented. No significant modification of kTy due to nuclear matter effects in p–Pb collisions with respect to the event multiplicity or a PYTHIA8 reference is observed.

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• Acharya, Shreyasi; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2017). Erratum to: Production of π0 and η mesons up to high transverse momentum in pp collisions at 2.76 TeV - Eur. Phys. J. C (2017) 77:339 DOI 10.1140/epjc/s10052-017-4890-x. European Physical Journal C. ISSN 1434-6044. 77:586, p. 1–7. doi: 10.1140/epjc/s10052-017-5144-7. Full text in Research Archive
• Adam, Jaroslav; Adamová, Dagmar; Aggarwal, Madan M.; Rinella, Gianluca Aglieri; Agnello, Michelangelo & Agrawal, Nikita [Show all 51 contributors for this article] (2016). ALICE Collaboration. Nuclear Physics A. ISSN 0375-9474. 956, p. 913–921. doi: 10.1016/S0375-9474(16)30231-7. Full text in Research Archive

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