Suppression of ψ(2S) production in p-Pb collisions at √sNN= 5.02 TeV

JHEP12(2014)073 Published for SISSA by Springer Received:May 30, 2014 Revised:October 14, 2014 Accepted:November 17, 2014 Published:December 10, 2014 Suppression of ψ(2S) production in p-Pb collisions at √sNN = 5.02 TeV The ALICE collaboration E-mail: [email protected] Abstract: The ALICE Collaboration has studied the inclusive production of the charmonium state ψ(2S) in proton-lead (p-Pb) collisions at the nucleon-nucleon centre of mass energy √sNN = 5.02 TeV at the CERN LHC. The measurement was performed at forward (2.03 < ycms <3.53) and backward (−4.46 < ycms <−2.96) centre of mass rapidities, studying the decays into muon pairs. In this paper, we present the inclusive production cross sections σψ(2S), both integrated and as a function of the transverse momentum pT, for the two ycms domains. The results are compared to those obtained for the 1S vector state (J/ψ), by showing the ratios between the production cross sections, as well as the double ratios [σψ(2S)/σJ/ψ]pPb/[σψ(2S)/σJ/ψ]pp between p-Pb and proton-proton collisions. Finally, the nuclear modification factor for inclusive ψ(2S) is evaluated and compared to the measurement of the same quantity for J/ψand to theoretical models including parton shadowing and coherent energy loss mechanisms. The results show a significantly larger suppression of the ψ(2S) compared to that measured for J/ψand to models. These observations represent a clear indication for sizeable final state effects on ψ(2S) production. Keywords: Charm physics, Heavy Ions ArXiv ePrint: 1405.3796 Open Access, Copyright CERN, for the benefit of the ALICE Collaboration. Article funded by SCOAP3. doi:10.1007/JHEP12(2014)073 JHEP12(2014)073 The physics of charmonia, bound states of the charm (c) and anti-charm (c) quarks, is an extremely broad and interesting field of investigation [1]. The description of the various states and the calculation of their production cross sections in hadronic collisions involve an interplay of perturbative and non-perturbative aspects of Quantum ChromoDynamics (QCD) [2], which still today represent a significant challenge for theory [3]. Charmonium states can have smaller sizes than light hadrons (down to a few tenths of a fm) and large binding energies (>500 MeV) [4]. These properties make charmonia a useful probe of the hot nuclear matter created in ultrarelativistic heavy-ion collisions, which can be seen as a plasma of deconfined quarks and gluons (QGP) (see [5] for a recent overview of QGP studies). In particular, the ccbinding can be screened by the high density of colour charges present in the QGP, leading to a suppression of the yields of charmonia in highenergy nuclear collisions compared to the corresponding production rates in elementary pp collisions at the same energy [6]. In the so-called “sequential suppression” scenario, the melting of a bound ccstate occurs when the temperature of the hot medium exceeds a threshold dissociation temperature [7,8], which depends on the binding energy of the state and can be calculated in lattice QCD [9]. At LHC energies, where the number of produced ccpairs is large, this suppression effect can be partly counterbalanced by charmonium “regeneration” processes due to the recombination of charm quarks that occurs as the system cools and hadrons form [10–12]. Among the charmonium states, the strongly bound S-wave J/ψand the weakly bound radially excited ψ(2S) have received most attention in the context of QGP studies. Both decay to lepton pairs with a non-negligible branching ratio (5.93% and 0.77%, respectively, for the µ+µ−channel [13]). The results obtained by the NA50 collaboration at the CERN SPS showed a significant suppression of the J/ψproduction in Pb-Pb collisions at √sNN = 17 GeV [14] and a comparatively larger suppression of the ψ(2S) [15], in qualitative agreement with sequential suppression models. However, the same experiment also detected a significant suppression of both states (although not as strong as in Pb-Pb) in proton-nucleus (p-A) collisions [16], where no QGP formation was expected. The same observation was made by other fixed-target experiments studying p-A collisions at Fermilab (E866 [17]) and HERA (HERA-B [18]). It was indeed realized that the charmonium yields are also sensitive to the presence of cold nuclear matter (CNM) in the target nucleus, and various mechanisms (nuclear parton shadowing [19], cc break-up via interaction with nucleons [20–22], initial/final state energy loss [23]) were taken into account in order to describe experimental observations. In particular, these experiments observed a stronger suppression for ψ(2S) relative to J/ψat central rapidity, while at forward rapidity no difference was found within uncertainties. This feature of the results was interpreted in terms of pair break-up: at central rapidity the time spent by the cc state in the nuclear medium (crossing time) is typically larger than the formation time of the resonances (∼0.1 fm/c[24,25]), so that the loosely bound ψ(2S) can be more easily dissociated than the J/ψ. Conversely, in forward production the crossing time is smaller than the formation time and the influence of the nucleus on the pre-hadronic state is the same, independent of the particular resonance being produced [26]. –1– JHEP12(2014)073 More generally, the study of charmonia in p-A collisions can be used as a tool for a quantitative investigation of the aforementioned processes, relevant in the context of studies of the strong interaction. Therefore, measurements at high energies are important to test our understanding of the various mechanisms. In particular, the pair break-up cross sections discussed above are expected to be strongly reduced due to the increasingly shorter time spent by the ccpair in CNM. On the other hand, the other effects listed above (shadowing, energy loss) are not expected to depend on the final quantum numbers of the charmonium states. In such a situation, a similar suppression for the two charmonium states should be observed in high-energy p-A collisions. In the context of comparative studies between the resonances, the PHENIX experiment at RHIC has recently published results on the ψ(2S) suppression at central rapidity for d-Au collisions at √sNN = 200 GeV [27], by studying the nuclear modification factor Rψ(2S) dAu = dNψ(2S) dAu /dy/(Ncoll×dNψ(2S) pp /dy), which corresponds to the ratio of the production yields in d-Au and pp at the same energy, normalized by the number of nucleon-nucleon collisions in d-Au. The ratio of the nuclear modification factors Rψ(2S) dAu /RJ/ψ dAu is found to be smaller than 1, and strongly decreasing from peripheral to central d-Au events. The observation of a ψ(2S) suppression stronger than that of the J/ψis in contrast to the expectation of a similar suppression as described above. Data from the LHC can be useful to shed further light on this observation, as nuclear crossing times [25] may be as low as 10−4fm/cfor charmonium production at forward rapidity, implying a negligible influence of pair break-up processes and, in more general terms, to test our understanding of charmonium propagation in CNM. In this Letter, we present the first measurement of inclusive ψ(2S) production in √sNN = 5.02 TeV p-Pb collisions at the LHC, carried out by the ALICE Collaboration, and we compare the results with those for J/ψ. The resonances were measured in the dimuon decay channel using the Muon Spectrometer (MS) [28], which covers the pseudorapidity range −4< ηlab <−2.5. The other detectors involved in this analysis are: (i) the two innermost layers of the Inner Tracking System (Silicon Pixel Detectors, SPD), used for the determination of the primary vertex of the interaction and covering |ηlab|<2.0 (first layer) and |ηlab|<1.4 (second layer) [29]; (ii) the two VZERO scintillator hodoscopes, used mainly for triggering purposes and covering −3.7< ηlab <−1.7 and 2.8< ηlab <5.1 [30]; (iii) the Zero Degree Calorimeters (ZDC), at 112.5 m from the interaction point [31], used to remove collisions outside the nominal timing of the LHC bunches. Details of the ALICE experimental setup are provided elsewhere [32]. Due to the LHC design, the colliding beams have different energies per nucleon (Ep= 4 TeV, EPb = 1.58 ·APb TeV, where APb = 208 is the mass number of the Pb nucleus). As a consequence, the centre of mass of the nucleon-nucleon collision is shifted by ∆y= 0.465 with respect to the laboratory frame in the direction of the proton beam. Data were taken in two configurations, by inverting the sense of the orbits of the two beams. In this way, both forward (2.03 < ycms <3.53) and backward (−4.46 < ycms <−2.96) centre of mass rapidities were covered, with the positive rapidity defined by the direction of the proton beam. We refer to the two data samples as p-Pb and Pb-p respectively. The integrated luminosities for the two data samples are LpPb int = 5.01±0.19 nb−1and LPbp int = 5.81±0.20 nb−1[33]. –2– JHEP12(2014)073 Data were collected with a dimuon trigger, defined as the coincidence of the minimumbias (MB) condition with the detection of two opposite-sign muon candidates in the trigger system of the MS. The MB condition is a coincidence between signals in the two VZERO hodoscopes and has >99% efficiency for non-single diffractive events [34]. For the muon candidates, a transverse momentum pT,µ = 0.5 GeV/ctrigger threshold is applied. The effect of this threshold is not sharp, and the single muon trigger efficiency reaches its plateau value (∼96%) for pT,µ ∼1.5 GeV/c. The offline event selection, the muon reconstruction and identification criteria and the kinematic cuts applied at the single and dimuon levels are identical to those described in [35]. In addition, a cut on the transverse distance from the primary vertex of each of the reconstructed muon tracks, weighted with its momentum (pDCA), was performed. Tracks with pDCA >6×σpDCA were rejected. The quantity σpDCA is the pDCA resolution, which is obtained from data, taking into account the resolution on track momentum and slope [36]. Such a track cut reduces the background continuum by a few percent without affecting the resonances. The extraction of the resonance signals is carried out by means of a fit to the dimuon invariant mass spectrum, as illustrated in figure 1for the two rapidity ranges under study. The J/ψand ψ(2S) line shapes are described either by Crystal Ball (CB) functions [37], with asymmetric tails on both sides of the peak, or by pseudo-Gaussian functions [38]. The parameters of the resonance shapes are obtained by means of a Monte-Carlo (MC) simulation. Pure J/ψand ψ(2S) signal samples are generated, and then tracked and reconstructed in the experimental setup with the same procedure applied to real data. The choice of the MC kinematic distributions of charmonia is discussed below when introducing the acceptance calculation. Due to the large signal to background ratio (S/B) in the J/ψ mass region and in order to account for small deviations of the mass (∼0.1%) and width (∼10%) between MC and data, the corresponding parameters are left free in the fit. For the ψ(2S), due to the less favourable S/B, the mass and widths are constrained by those for the J/ψusing the following relations, which involve the corresponding MC quantities: mψ(2S) =mJ/ψ + (mMC ψ(2S) −mMC J/ψ) and σψ(2S) =σJ/ψ ·(σMC ψ(2S)/σMC J/ψ). Alternative values of the ψ(2S) mass resolution have also been tested, allowing the ratio (σMC ψ(2S)/σMC J/ψ) to vary within 10% [36]. Finally, the parameters of the asymmetric tails, which can hardly be constrained by the data, are kept fixed to their MC values. Additional sets of tails, obtained from the MC, but sampling the ycms and pTphase space, have also been tested. The dependence of the extracted J/ψand ψ(2S) yields on the variation of the tails and on the ψ(2S) mass resolution is included in the systematic uncertainty on the signal extraction. The background continuum under the resonances is parameterized by empirical shapes, using a polynomial times an exponential function or a Gaussian having a width increasing with mass. In order to assess the systematic uncertainty on signal extraction, fits with various combinations of the signal and background shapes are performed, and the start/end point of the fit range is also varied. The raw ψ(2S) yields and their statistical uncertainty is finally obtained as the average of the results of the various fits performed, while the systematic uncertainty is calculated as the root-mean-square (RMS) of their distribution. This results in Nψ(2S) pPb = 1069 ±130 ±102 and Nψ(2S) Pbp = 697 ±111 ±65, where the first uncertainty is –3– JHEP12(2014)073 ) 2 c (GeV/ - µ + µ m 2 2.5 3 3.5 4 4.5 5 2 cCounts per 50 MeV/ 2 10 3 10 4 10 /ndf = 1.33 2 χ = 5.02 TeV NN s ALICE, p-Pb > 0 T p < 3.53, cms y2.03 < ) 2 c (GeV/ - µ + µ m 2 2.5 3 3.5 4 4.5 5 2 cCounts per 50 MeV/ 2 10 3 10 4 10 /ndf = 1.39 2 χ = 5.02 TeV NN s ALICE, p-Pb > 0 T p < -2.96, cms y-4.46 < Figure 1. Opposite-sign dimuon invariant mass spectra for the p-Pb (left) and Pb-p (right) data samples, together with the result of a fit. For the fits shown here, Crystal Ball functions (shown as dashed lines) and a variable-width Gaussian have been used for the resonances and the background, respectively. The χ2/ndf refers to the goodness of the signal and background combined fit in the displayed mass range. statistical and the second is systematic. The ψ(2S) mass resolution extracted from the fits is ∼70 MeV/c2. As a cross-check, an alternative approach for signal extraction, based on event counting, was also tested. More precisely, after fitting the invariant mass distribution and subtracting the background contribution, the number of ψ(2S) was obtained by integrating the background subtracted spectrum in the region 3.5< mµµ <3.8 GeV/c2. Corrections, based on the signal fitting functions, were applied to the measured number of counts to account for the fraction of ψ(2S) outside of the integration region (∼15%) and for the number of J/ψfalling inside the ψ(2S) mass range (∼8%). The results were found to be stable within 1% with respect to 0.1 GeV/c2variations of the integration region. The number of J/ψand ψ(2S) extracted in this way are also in excellent agreement (i.e., well within the systematic uncertainties) with respect to the Nψ(2S) pPb and Nψ(2S) Pbp values quoted above. The acceptance times efficiency values (A ×ǫ) for the ψ(2S) were evaluated using MC simulations in a similar way as detailed in [35] for the J/ψ. The input pTdistributions were obtained from those used for the J/ψ[35], scaled such that hpTiψ(2S) pPb,5.02 TeV = hpTiJ/ψ pPb,5.02 TeV ×(hpTiψ(2S) pp,7 TeV/hpTiJ/ψ pp,7 TeV), and using the √s= 7 TeV pp values from LHCb [39,40] obtained in the slightly larger range 2 < ycms <4.5. The input ydistributions were obtained from those used for the J/ψassuming a scaling of the widths with yψ(2S) max /yJ/ψ max, where yi max = log(√s/mi) is the maximum rapidity for the resonance iat the √svalue under study. An unpolarized distribution for the ψ(2S) was assumed, according to the results obtained in pp collisions at √s= 7 TeV by the CMS and LHCb experiments [41,42]. The systematic uncertainty for the ψ(2S) acceptance was calculated as the maximum spread of the values obtained by assuming as alternative input distributions those used for the J/ψitself and amounts to 1.8% (2.5%) for p-Pb (Pb-p). The efficiency of the tracking and trigger detectors of the MS was taken into account in the MC simulations by means of a map of dead channels (tracking) and by building efficiency tables for the detector elements (trigger). The evolution of the detector performance –4– JHEP12(2014)073 throughout the data taking was followed in the MC, by generating a number of events which is proportional to the run-by-run number of dimuon triggers, in order to properly weight the detector conditions over the entire data taking. The systematic uncertainties on the efficiencies were obtained with algorithms based on real data, with the same procedure adopted in [35], and they are identical for J/ψand ψ(2S). A small uncertainty related to the efficiency of the matching between tracking and triggering information was also included [35]. The pT-integrated A ×ǫvalues for ψ(2S) production, obtained with this procedure, are 0.270±0.014 (p-Pb) and 0.184±0.013 (Pb-p), where the lower value for Pb-p is mainly due to a smaller detector efficiency in the corresponding data taking period, related to a worse detector performance. The quoted uncertainties are systematic and are obtained as the quadratic sum of the uncertainties on MC input, tracking, triggering and matching efficiencies. The statistical uncertainties are negligible. The cross section times the branching ratio B.R.(ψ(2S) →µµ) for inclusive ψ(2S) production in p-Pb collisions (and similarly for Pb-p) is: B.R.ψ(2S)→µ+µ−·σψ(2S) pPb =Ncor ψ(2S)→µµ LpPb int (1) where Ncor ψ(2S)→µµ is the number of ψ(2S) corrected for A ×ǫ, and LpPb int is the integrated luminosity, calculated as NMB/σMB pPb.NMB is the number of MB events, obtained as the number of dimuon triggers divided by the probability of having a triggered dimuon in a MB event. The NMB numerical values and uncertainties are the same as those quoted in [35]. The cross sections for the occurrence of the MB condition, σMB pPb, are measured in a vdM scan [33] to be 2.09 ±0.07 b for the p-Pb configuration and 2.12 ±0.07 b for the Pb-p one. The luminosity is also independently determined by means of a second luminosity signal, as described in [33]. The two measurements differ by at most 1% throughout the whole data-taking period and such a value is quadratically added to the luminosity uncertainty. The ψ(2S) cross section values are: B.R.·σψ(2S) pPb (2.03 < ycms <3.53) = 0.791 ±0.096(stat.)±0.091(syst.uncorr.)±0.013(syst.corr.)µb B.R.·σψ(2S) Pbp (−4.46 < ycms <−2.96) = 0.653 ±0.104(stat.)±0.080(syst.uncorr.)±0.010(syst.corr.)µb The systematic uncertainties for the ψ(2S) cross section measurement are obtained as the quadratic sum of the various contributions listed in table 1. The splitting between uncorrelated and correlated sources is also summarized there. The corresponding values for the J/ψcan be found in [35]. The study of the cross section ratio between ψ(2S) and J/ψ, and the comparison of this ratio between different systems, offers a powerful tool to investigate nuclear effects on charmonium production. In addition, several systematic uncertainties cancel, or are significantly reduced, when studying such ratios. In particular, in the present analysis, the tracking, trigger and matching efficiencies, as well as the normalization-related quantities, cancel out. For the MC input, the fraction of the uncertainty related to the choice of the J/ψkinematical distribution [35] cancels in the cross section ratios, and the remaining 1% –5– JHEP12(2014)073 B.R.·σψ(2S) pPb B.R.·σψ(2S) Pbp Tracking efficiency 4 6 Trigger efficiency 2.8 (2 −3.5) 3.2 (2 −3.5) Signal extraction 9.5 (8 −11.9) 9.3 (8.6 −12.7) MC input 1.8 (1.5 −1.5) 2.5 (1.5 −1.7) Matching efficiency 1 1 Lint(uncorr.) 3.4 3.1 Lint(corr.) 1.6 1.6 Table 1. Systematic uncertainties (in percent) affecting the measurement of inclusive ψ(2S) cross sections. The Lint uncertainties are splitted in two components, respectively uncorrelated and correlated between p-Pb and Pb-p, as detailed in [33]. All the other uncertainties are uncorrelated between forward and backward rapidity. Uncertainties refer to pT-integrated quantities and, where they depend on pT, the corresponding maximum and minimum values are also quoted. The efficiency-related uncertainties refer to muon pairs. (2%) uncertainty for p-Pb (Pb-p) is assigned to this source. Finally, the uncertainty on signal extraction is considered as uncorrelated between J/ψand ψ(2S), and its value for the cross section ratios amounts to 10% for both p-Pb and Pb-p. The resulting values are: B.R.ψ(2S)→µ+µ−σψ(2S) B.R.J/ψ→µ+µ−σJ/ψ (2.03 < ycms <3.53) = 0.0154 ±0.0019(stat.)±0.0015(syst.) B.R.ψ(2S)→µ+µ−σψ(2S) B.R.J/ψ→µ+µ−σJ/ψ (−4.46 < ycms <−2.96) = 0.0116 ±0.0018(stat.)±0.0011(syst.) In figure 2we compare these ratios with the corresponding ALICE results for pp collisions [36], obtained in slightly different centre of mass energy and rapidity regions, √s = 7 TeV, 2.5<|y|<4, as no LHC pp results are available in the same kinematic conditions of proton-nucleus collisions. The pp ratios are significantly higher than those for p-Pb and Pb-p, which are compatible within uncertainties. The double ratio [σψ(2S)/σJ/ψ]pPb/[σψ(2S)/σJ/ψ]pp is a useful quantity to directly compare the relative suppression of the two states between various experiments. For this analysis, since the collision energy and the y-coverage of the p-Pb (Pb-p) and pp measurements are different, we have estimated the possible dependence of the σψ(2S)/σJ/ψ vs √sand yin pp collisions. We start from the empirical observation that this ratio is very similar at collider energies over a rather broad range of yand √s. In particular, from the LHCb data (√s= 7 TeV, 2 < y < 4.5) [39,40] one gets 2.11% for the inclusive ratio integrated over pT, while the corresponding value from CDF data (pp at √s= 1.96 TeV, |y|<0.6) [43] is 2.05%, i.e., only 3% smaller (the latter quantity was obtained by extrapolating the CDF ψ(2S) measurement to pT= 0 with the phenomenological function f(pT) = (pT)/[1+(pT/a)2]b) [44]. The LHCb result can be extrapolated to central rapidity at √s= 7 TeV, assuming a Gaussian y-distribution for both resonances, with the width of the J/ψdistribution tuned directly on data [39] and that for ψ(2S) obtained from the former –6– JHEP12(2014)073 cms y -5 -4 -3 -2 -1 0 1 2 3 4 5 ψJ/ σ - µ + µ→ψJ/ /B.R. (2S)ψ σ - µ + µ→(2S)ψ B.R. 0 0.005 0.01 0.015 0.02 0.025 0.03 0.035 0.04 - µ + µ→(2S)ψ, ψALICE, Inclusive J/ = 0) cms y= 7 TeV (open symbol: reflected around spp = 5.02 TeV NN sp-Pb Figure 2. The cross section ratios B.R.ψ(2S)→µ+µ−σψ(2S)/B.R.J/ψ→µ+µ−σJ/ψ for p-Pb and Pb-p collisions, compared with the corresponding pp results at √s= 7 TeV [36]. The horizontal bars correspond to the width of the rapidity regions under study. The vertical error bars represent statistical uncertainties, the boxes correspond to systematic uncertainties. assuming a scaling of the widths with yψ(2S) max /yJ/ψ max. The effect of this rescaling is small, leading to a 3% increase of the ratio. The central-rapidity ratio σψ(2S)/σJ/ψ at √s= 5.02 TeV is then obtained by means of an interpolation between the CDF and LHCb-rescaled values, assuming a linear dependence of the ratio vs √s. Finally, one can extrapolate the ratio to the p-Pb and Pb-p rapidity ranges by using for the J/ψthe Gaussian shape obtained with the interpolation procedure described in [45] and for the ψ(2S) the corresponding shape scaled with yψ(2S) max /yJ/ψ max. The difference between the measured value of σψ(2S)/σJ/ψ for √s = 7 TeV, 2 < ycms <4.5 and the results of the interpolation procedure to √s= 5.02 TeV, 2.03 < ycms <3.53 (−4.46 < ycms <−2.96) is -1.6% (-3.7%). When calculating the double ratio [σψ(2S)/σJ/ψ]pPb/[σψ(2S)/σJ/ψ]pp, we choose to use for pp the measured value at √s = 7 TeV, 2.5< ycms <4 [36] (rather than the interpolated one at √s= 5.02 TeV) and to include a 8% systematic uncertainty on this quantity, i.e., about twice the maximum difference between the measured values of the ratio in pp and the results of the interpolation procedure. A similar uncertainty would be obtained using as an input for the calculation, instead of the LHCb data, the more recent pp result from ALICE on σψ(2S)/σJ/ψ [36]. The values of the double ratio are shown in figure 3, where they are also compared with the corresponding results obtained by the PHENIX experiment at √sNN = 200 GeV, for |y|<0.35 [27]. When forming the double ratio, the systematic uncertainties on the pp ratio, including the 8% contribution described in the previous paragraph, are considered as correlated between forward and backward rapidity, while the other systematic uncertainties are treated as uncorrelated. The dominating contributions to the systematic uncertainty come from the signal extraction and from the interpolation procedure used for the pp cross –7– JHEP12(2014)073 cms y -5 -4 -3 -2 -1 0 1 2 3 4 5 pp ] ψJ/ σ / (2S)ψ σ / [ pPb (dAu) ] ψJ/ σ / (2S)ψ σ[ 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 = 5.02 TeV NN sALICE, p-Pb, = 0.2 TeV NN sPHENIX, d-Au, Figure 3. Double ratios [σψ(2S)/σJ/ψ]pPb/[σψ(2S)/σJ/ψ]pp for p-Pb and Pb-p collisions, compared to the corresponding PHENIX result at √sNN = 200 GeV [27]. The horizontal bars correspond to the width of the rapidity regions under study. For ALICE, the vertical error bars correspond to statistical uncertainties, the boxes to uncorrelated systematic uncertainties, and the shaded areas to correlated uncertainties. For PHENIX, the various sources of systematic uncertainties were combined in quadrature. section. The ALICE results show that, compared to pp, the ψ(2S) is more suppressed than the J/ψto a 2.3σ(4.1σ) level in p-Pb (Pb-p). The PHENIX result shows a similar feature, at a 1.3σlevel. The suppression of charmonium states with respect to the corresponding pp yield can be quantified using the nuclear modification factor. For ψ(2S), Rψ(2S) pPb is obtained by combining RJ/ψ pPb [35] with the double ratio evaluated above: Rψ(2S) pPb =RJ/ψ pPb ·σψ(2S) pPb σJ/ψ pPb ·σJ/ψ pp σψ(2S) pp (2) In figure 4,Rψ(2S) pPb is shown and compared with RJ/ψ pPb. For the double ratios, the difference in the √sand ydomains between p-Pb and pp is taken into account by the inclusion of the 8% systematic uncertainty described above. The other quoted uncertainties combine those from RJ/ψ pPb [35] with those for the double ratio, avoiding a double counting of the J/ψrelated uncertainties. Figure 4indicates that the ψ(2S) suppression is much stronger than for the J/ψand reaches a factor ∼2 with respect to pp. The results are compared with theoretical calculations including either nuclear shadowing only [46,47] or coherent energy loss, with or without a shadowing contribution [48]. For the former mechanism, the values correspond to calculations performed for the J/ψ. However, due to the relatively similar kinematic distributions of gluons that produce the ccpair which will then hadronize to a J/ψor a ψ(2S), the shadowing effects are expected to be the same, –8– JHEP12(2014)073 [12] A. Andronic, P. Braun-Munzinger, K. Redlich and J. Stachel, Statistical hadronization of heavy quarks in ultra-relativistic nucleus-nucleus collisions,Nucl. Phys. A 789 (2007) 334 [nucl-th/0611023] [INSPIRE]. [13] Particle Data Group collaboration, J. Beringer et al., Review of particle physics (RPP), Phys. Rev. D 86 (2012) 010001 [INSPIRE]. [14] NA50 collaboration, B. Alessandro et al., A new measurement of J/ψ suppression in Pb-Pb collisions at 158 GeV per nucleon,Eur. Phys. J. C 39 (2005) 335 [hep-ex/0412036] [INSPIRE]. [15] NA50 collaboration, B. Alessandro et al., ψ′production in Pb-Pb collisions at 158 GeV/nucleon,Eur. Phys. J. C 49 (2007) 559 [nucl-ex/0612013] [INSPIRE]. [16] NA50 collaboration, B. Alessandro et al., J/ψ and ψ′production and their normal nuclear absorption in proton-nucleus collisions at 400 GeV,Eur. Phys. J. C 48 (2006) 329 [nucl-ex/0612012] [INSPIRE]. [17] NuSea collaboration, M.J. Leitch et al., Measurement of J/ψ and ψ′suppression in p-A collisions at 800 GeV/c,Phys. Rev. Lett. 84 (2000) 3256 [nucl-ex/9909007] [INSPIRE]. [18] HERA-B collaboration, I. Abt et al., A measurement of the ψ′to J/ψ production ratio in 920 GeV proton-nucleus interactions,Eur. Phys. J. C 49 (2007) 545 [hep-ex/0607046] [INSPIRE]. [19] K.J. Eskola, H. Paukkunen and C.A. Salgado, EP S09: a new generation of NLO and LO nuclear parton distribution functions,JHEP 04 (2009) 065 [arXiv:0902.4154] [INSPIRE]. [20] R. Vogt, Are the J/ψ and χcA dependencies the same?,Nucl. Phys. A 700 (2002) 539 [hep-ph/0107045] [INSPIRE]. [21] B.Z. Kopeliovich and B.G. Zakharov, Quantum effects and color transparency in charmonium photoproduction on nuclei,Phys. Rev. D 44 (1991) 3466 [INSPIRE]. [22] D.C. McGlinchey, A.D. Frawley and R. Vogt, Impact parameter dependence of the nuclear modification of J/ψ production in d+Au collisions at √sNN = 200 GeV, Phys. Rev. C 87 (2013) 054910 [arXiv:1208.2667] [INSPIRE]. [23] F. Arleo and S. Peigne, J/ψ suppression in p-A collisions from parton energy loss in cold QCD matter,Phys. Rev. Lett. 109 (2012) 122301 [arXiv:1204.4609] [INSPIRE]. [24] F. Arleo, P.B. Gossiaux, T. Gousset and J. Aichelin, Charmonium suppression in p-A collisions,Phys. Rev. C 61 (2000) 054906 [hep-ph/9907286] [INSPIRE]. [25] D.C. McGlinchey, A.D. Frawley and R. Vogt, Impact parameter dependence of the nuclear modification of J/ψ production in d+Au collisions at √sNN = 200 GeV, Phys. Rev. C 87 (2013) 054910 [arXiv:1208.2667] [INSPIRE]. [26] R. Vogt, The xFdependence of ψand Drell-Yan production,Phys. Rev. C 61 (2000) 035203 [hep-ph/9907317] [INSPIRE]. [27] PHENIX collaboration, A. Adare et al., Nuclear modification of ψ′,χcand J/ψ production in d+Au collisions at √sNN = 200 GeV,Phys. Rev. Lett. 111 (2013) 202301 [arXiv:1305.5516] [INSPIRE]. [28] ALICE collaboration, Rapidity and transverse momentum dependence of inclusive J/ψ production in pp collisions at √s= 7 TeV,Phys. Lett. B 704 (2011) 442 [Erratum ibid. B 718 (2012) 692] [arXiv:1105.0380] [INSPIRE]. – 15 – JHEP12(2014)073 [29] ALICE collaboration, Alignment of the ALICE Inner Tracking System with cosmic-ray tracks,2010 JINST 5P03003 [arXiv:1001.0502] [INSPIRE]. [30] ALICE collaboration, Performance of the ALICE VZERO system,2013 JINST 8P10016 [arXiv:1306.3130] [INSPIRE]. [31] ALICE collaboration, Measurement of the cross section for electromagnetic dissociation with neutron emission in Pb-Pb collisions at √sNN = 2.76 TeV, Phys. Rev. Lett. 109 (2012) 252302 [arXiv:1203.2436] [INSPIRE]. [32] ALICE collaboration, The ALICE experiment at the CERN LHC,2008 JINST 3S08002 [INSPIRE]. [33] ALICE collaboration, Measurement of visible cross sections in proton-lead collisions at √sNN = 5.02 TeV in van der Meer scans with the ALICE detector,2014 JINST 9P11003 [arXiv:1405.1849] [INSPIRE]. [34] ALICE collaboration, Pseudorapidity density of charged particles p-Pb collisions at √sNN = 5.02 TeV,Phys. Rev. Lett. 110 (2013) 032301 [arXiv:1210.3615] [INSPIRE]. [35] ALICE collaboration, J/ψ production and nuclear effects in p-Pb collisions at √sNN = 5.02 TeV,JHEP 02 (2014) 073 [arXiv:1308.6726] [INSPIRE]. [36] ALICE collaboration, Measurement of quarkonium production at forward rapidity in pp collisions at √s= 7 TeV,Eur. Phys. J. C 74 (2014) 2974 [arXiv:1403.3648] [INSPIRE]. [37] J. Gaiser, Line shape and resolution, in Charmonium spectroscdpy from radiative decays of the J/ψ and ψ′,SLAC-255, SLAC, Stanford U.S.A. (1982), pg. 177 [INSPIRE]. [38] R. Shahoyan, J/ψ and ψ′production in 450 GeV pA interactions and its dependence on the rapidity and XF, Ph.D. thesis, http://www.cern.ch/NA50/theses/ruben.ps.gz, Instituto Superior T´ecnico, Lisbon Portugal (2001). [39] LHCb collaboration, Measurement of J/ψ polarization in pp collisions at √s= 7 TeV, Eur. Phys. J. C 73 (2013) 2631 [arXiv:1307.6379] [INSPIRE]. [40] LHCb collaboration, Measurement of ψ(2S)meson production in pp collisions at √s= 7 TeV,Eur. Phys. J. C 72 (2012) 2100 [arXiv:1204.1258] [INSPIRE]. [41] CMS collaboration, Measurement of the prompt J/ψ and ψ(2S)polarizations in pp collisions at √s= 7 TeV,Phys. Lett. B 727 (2013) 381 [arXiv:1307.6070] [INSPIRE]. [42] LHCb collaboration, Measurement of ψ(2S)polarisation in pp collisions at √s= 7 TeV, Eur. Phys. J. C 74 (2014) 2872 [arXiv:1403.1339] [INSPIRE]. [43] CDF collaboration, T. Aaltonen et al., Production of ψ(2S)mesons in p¯pcollisions at 1.96 TeV,Phys. Rev. D 80 (2009) 031103 [arXiv:0905.1982] [INSPIRE]. [44] PHENIX collaboration, A. Adare et al., J/ψ production versus transverse momentum and rapidity in p+pcollisions at √s= 200 GeV,Phys. Rev. Lett. 98 (2007) 232002 [hep-ex/0611020] [INSPIRE]. [45] ALICE and LHCb collaborations, Reference pp cross-sections for J/ψ studies in proton-lead collisions at √sNN = 5.02 TeV and comparisons between ALICE and LHCb results, ALICE-PUBLIC-2013-002, CERN, Geneva Switzerland (2013) [LHCb-CONF-2013-013]. [46] J.L. Albacete et al., Predictions for p+Pb collisions at √sNN = 5 TeV, Int. J. Mod. Phys. E 22 (2013) 1330007 [arXiv:1301.3395] [INSPIRE]. [47] R. Vogt, private communication. – 16 – JHEP12(2014)073 [48] F. Arleo and S. Peigne, Heavy-quarkonium suppression in p-A collisions from parton energy loss in cold QCD matter,JHEP 03 (2013) 122 [arXiv:1212.0434] [INSPIRE]. [49] E.G. Ferreiro, F. Fleuret, J.P. Lansberg and A. Rakotozafindrabe, J/ψ and ψ′production in proton(deuteron)-nucleus collisions: lessons from RHIC for the proton-lead LHC run, J. Phys. Conf. Ser. 422 (2013) 012018 [arXiv:1211.4749] [INSPIRE]. [50] E.G. Ferreiro, private communication. [51] F. Arleo, private communication. [52] M.L. Miller, K. Reygers, S.J. Sanders and P. Steinberg, Glauber modeling in high energy nuclear collisions,Ann. Rev. Nucl. Part. Sci. 57 (2007) 205 [nucl-ex/0701025] [INSPIRE]. [53] ALICE collaboration, B. Abelev et al., Rapidity and transverse momentum dependence of the inclusive J/ψ nuclear modification factor in p-Pb collisions at √sNN = 5.02 TeV, in preparation. – 17 – JHEP12(2014)073 The ALICE collaboration B. Abelev69, J. Adam37, D. Adamov´a77, M.M. Aggarwal81, M. Agnello105,88, A. Agostinelli26, N. Agrawal44, Z. Ahammed124, N. Ahmad18, I. Ahmed15, S.U. Ahn62, S.A. Ahn62, I. Aimo105,88, S. Aiola129, M. Ajaz15, A. Akindinov53, S.N. Alam124, D. Aleksandrov94, B. Alessandro105, D. Alexandre96, A. Alici12,99, A. Alkin3, J. Alme35, T. Alt39, S. Altinpinar17, I. Altsybeev123, C. Alves Garcia Prado113, C. Andrei72, A. Andronic91, V. Anguelov87, J. Anielski49, T. Antiˇci´c92, F. Antinori102, P. Antonioli99, L. Aphecetche107, H. Appelsh¨auser48, S. Arcelli26, N. Armesto16, R. Arnaldi105, T. Aronsson129, I.C. Arsene91, M. Arslandok48, A. Augustinus34, R. Averbeck91, T.C. Awes78, M.D. Azmi83, M. Bach39, A. Badal`a101, Y.W. Baek40,64, S. Bagnasco105, R. Bailhache48, R. Bala84, A. Baldisseri14, F. Baltasar Dos Santos Pedrosa34, R.C. Baral56, R. Barbera27, F. Barile31, G.G. Barnaf¨oldi128, L.S. Barnby96, V. Barret64, J. Bartke110, M. Basile26, N. Bastid64, S. Basu124, B. Bathen49, G. Batigne107, A. Batista Camejo64, B. Batyunya61, P.C. Batzing21, C. Baumann48, I.G. Bearden74, H. Beck48, C. Bedda88, N.K. Behera44, I. Belikov50, F. Bellini26, R. Bellwied115, E. Belmont-Moreno59, R. Belmont III127, V. Belyaev70, G. Bencedi128, S. Beole25, I. Berceanu72, A. Bercuci72, Y. BerdnikovII,79, D. Berenyi128, M.E. Berger86, R.A. Bertens52, D. Berzano25, L. Betev34, A. Bhasin84, I.R. Bhat84, A.K. Bhati81, B. Bhattacharjee41, J. Bhom120, L. Bianchi25, N. Bianchi66, C. Bianchin52, J. Bielˇc´ık37, J. Bielˇc´ıkov´a77, A. Bilandzic74, S. Bjelogrlic52, F. Blanco10, D. Blau94, C. Blume48, F. Bock68,87, A. Bogdanov70, H. Bøggild74, M. Bogolyubsky106, F.V. B¨ohmer86, L. Boldizs´ar128, M. Bombara38, J. Book48, H. Borel14, A. Borissov127,90, F. Boss´u60, M. Botje75, E. Botta25, S. B¨ottger47, P. Braun-Munzinger91, M. Bregant113, T. Breitner47, T.A. Broker48, T.A. Browning89, M. Broz37, E. Bruna105, G.E. Bruno31, D. Budnikov93, H. Buesching48, S. Bufalino105, P. Buncic34, O. Busch87, Z. Buthelezi60, D. Caffarri28, X. Cai7, H. Caines129, L. Calero Diaz66, A. Caliva52, E. Calvo Villar97, P. Camerini24, F. Carena34, W. Carena34, J. Castillo Castellanos14, E.A.R. Casula23, V. Catanescu72, C. Cavicchioli34, C. Ceballos Sanchez9, J. Cepila37, P. Cerello105, B. Chang116, S. Chapeland34, J.L. Charvet14, S. Chattopadhyay124, S. Chattopadhyay95, V. Chelnokov3, M. Cherney80, C. Cheshkov122, B. Cheynis122, V. Chibante Barroso34, D.D. Chinellato115, P. Chochula34, M. Chojnacki74, S. Choudhury124, P. Christakoglou75, C.H. Christensen74, P. Christiansen32, T. Chujo120, S.U. Chung90, C. Cicalo100, L. Cifarelli26,12, F. Cindolo99, J. Cleymans83, F. Colamaria31, D. Colella31, A. Collu23, M. Colocci26, G. Conesa Balbastre65, Z. Conesa del Valle46, M.E. Connors129, J.G. Contreras11, T.M. Cormier127, Y. Corrales Morales25, P. Cortese30, I. Cort´es Maldonado2, M.R. Cosentino113, F. Costa34, P. Crochet64, R. Cruz Albino11, E. Cuautle58, L. Cunqueiro66, A. Dainese102, R. Dang7, A. Danu57, D. Das95, I. Das46, K. Das95, S. Das4, A. Dash114, S. Dash44, S. De124, H. DelagrangeI,107, A. Deloff71, E. D´enes128, G. D’Erasmo31, A. De Caro29,12, G. de Cataldo98, J. de Cuveland39, A. De Falco23, D. De Gruttola29,12, N. De Marco105, S. De Pasquale29, R. de Rooij52, M.A. Diaz Corchero10, T. Dietel49, P. Dillenseger48, R. Divi`a34, D. Di Bari31, S. Di Liberto103, A. Di Mauro34, P. Di Nezza66, Ø. Djuvsland17, A. Dobrin52, T. Dobrowolski71, D. Domenicis Gimenez113, B. D¨onigus48, O. Dordic21, S. Dørheim86, A.K. Dubey124, A. Dubla52, L. Ducroux122, P. Dupieux64, A.K. Dutta Majumdar95, T. E. Hilden42, R.J. Ehlers129, D. Elia98, H. Engel47, B. Erazmus34,107, H.A. Erdal35, D. Eschweiler39, B. Espagnon46, M. Esposito34, M. Estienne107, S. Esumi120, D. Evans96, S. Evdokimov106, D. Fabris102, J. Faivre65, D. Falchieri26, A. Fantoni66, M. Fasel87, D. Fehlker17, L. Feldkamp49, D. Felea57, A. Feliciello105, G. Feofilov123, J. Ferencei77, A. Fern´andez T´ellez2, E.G. Ferreiro16, A. Ferretti25, A. Festanti28, J. Figiel110, M.A.S. Figueredo117, S. Filchagin93, D. Finogeev51, F.M. Fionda31, E.M. Fiore31, E. Floratos82, M. Floris34, S. Foertsch60, P. Foka91, S. Fokin94, E. Fragiacomo104, A. Francescon34,28, – 18 – JHEP12(2014)073 U. Frankenfeld91, U. Fuchs34, C. Furget65, M. Fusco Girard29, J.J. Gaardhøje74, M. Gagliardi25, A.M. Gago97, M. Gallio25, D.R. Gangadharan19, P. Ganoti78, C. Garabatos91, E. Garcia-Solis13, C. Gargiulo34, I. Garishvili69, J. Gerhard39, M. Germain107, A. Gheata34, M. Gheata34,57, B. Ghidini31, P. Ghosh124, S.K. Ghosh4, P. Gianotti66, P. Giubellino34, E. Gladysz-Dziadus110, P. Gl¨assel87, A. Gomez Ramirez47, P. Gonz´alez-Zamora10, S. Gorbunov39, L. G¨orlich110, S. Gotovac109, L.K. Graczykowski126, A. Grelli52, A. Grigoras34, C. Grigoras34, V. Grigoriev70, A. Grigoryan1, S. Grigoryan61, B. Grinyov3, N. Grion104, J.F. Grosse-Oetringhaus34, J.-Y. Grossiord122, R. Grosso34, F. Guber51, R. Guernane65, B. Guerzoni26, M. Guilbaud122, K. Gulbrandsen74, H. Gulkanyan1, M. Gumbo83, T. Gunji119, A. Gupta84, R. Gupta84, K. H. Khan15, R. Haake49, Ø. Haaland17, C. Hadjidakis46, M. Haiduc57, H. Hamagaki119, G. Hamar128, L.D. Hanratty96, A. Hansen74, J.W. Harris129, H. Hartmann39, A. Harton13, D. Hatzifotiadou99, S. Hayashi119, S.T. Heckel48, M. Heide49, H. Helstrup35, A. Herghelegiu72, G. Herrera Corral11, B.A. Hess33, K.F. Hetland35, B. Hippolyte50, J. Hladky55, P. Hristov34, M. Huang17, T.J. Humanic19, N. Hussain41, D. Hutter39, D.S. Hwang20, R. Ilkaev93, I. Ilkiv71, M. Inaba120, G.M. Innocenti25, C. Ionita34, M. Ippolitov94, M. Irfan18, M. Ivanov91, V. Ivanov79, A. Jacho lkowski27, P.M. Jacobs68, C. Jahnke113, H.J. Jang62, M.A. Janik126, P.H.S.Y. Jayarathna115, C. Jena28, S. Jena115, R.T. Jimenez Bustamante58, P.G. Jones96, H. Jung40, A. Jusko96, V. Kadyshevskiy61, S. Kalcher39, P. Kalinak54, A. Kalweit34, J. Kamin48, J.H. Kang130, V. Kaplin70, S. Kar124, A. Karasu Uysal63, O. Karavichev51, T. Karavicheva51, E. Karpechev51, U. Kebschull47, R. Keidel131, D.L.D. Keijdener52, M. Keil SVN34, M.M. KhanIII,18, P. Khan95, S.A. Khan124, A. Khanzadeev79, Y. Kharlov106, B. Kileng35, B. Kim130, D.W. Kim62,40, D.J. Kim116, J.S. Kim40, M. Kim40, M. Kim130, S. Kim20, T. Kim130, S. Kirsch39, I. Kisel39, S. Kiselev53, A. Kisiel126, G. Kiss128, J.L. Klay6, J. Klein87, C. Klein-B¨osing49, A. Kluge34, M.L. Knichel91, A.G. Knospe111, C. Kobdaj34,108, M. Kofarago34, M.K. K¨ohler91, T. Kollegger39, A. Kolojvari123, V. Kondratiev123, N. Kondratyeva70, A. Konevskikh51, V. Kovalenko123, M. Kowalski110, S. Kox65, G. Koyithatta Meethaleveedu44, J. Kral116, I. Kr´alik54, F. Kramer48, A. Kravˇc´akov´a38, M. Krelina37, M. Kretz39, M. Krivda96,54, F. Krizek77, E. Kryshen34, M. Krzewicki91, V. Kuˇcera77, Y. KucheriaevI,94, T. Kugathasan34, C. Kuhn50, P.G. Kuijer75, I. Kulakov48, J. Kumar44, P. Kurashvili71, A. Kurepin51, A.B. Kurepin51, A. Kuryakin93, S. Kushpil77, M.J. Kweon87, Y. Kwon130, P. Ladron de Guevara58, C. Lagana Fernandes113, I. Lakomov46, R. Langoy125, C. Lara47, A. Lardeux107, A. Lattuca25, S.L. La Pointe52, P. La Rocca27, R. Lea24, L. Leardini87, G.R. Lee96, I. Legrand34, J. Lehnert48, R.C. Lemmon76, V. Lenti98, E. Leogrande52, M. Leoncino25, I. Le´on Monz´on112, P. L´evai128, S. Li64,7, J. Lien125, R. Lietava96, S. Lindal21, V. Lindenstruth39, C. Lippmann91, M.A. Lisa19, H.M. Ljunggren32, D.F. Lodato52, P.I. Loenne17, V.R. Loggins127, V. Loginov70, D. Lohner87, C. Loizides68, X. Lopez64, E. L´opez Torres9, X.-G. Lu87, P. Luettig48, M. Lunardon28, G. Luparello52, R. Ma129, A. Maevskaya51, M. Mager34, D.P. Mahapatra56, S.M. Mahmood21, A. Maire87, R.D. Majka129, M. Malaev79, I. Maldonado Cervantes58, L. MalininaIV,61, D. Mal’Kevich53, P. Malzacher91, A. Mamonov93, L. Manceau105, V. Manko94, F. Manso64, V. Manzari98, M. Marchisone64,25, J. Mareˇs55, G.V. Margagliotti24, A. Margotti99, A. Mar´ın91, C. Markert111, M. Marquard48, I. Martashvili118, N.A. Martin91, P. Martinengo34, M.I. Mart´ınez2, G. Mart´ınez Garc´ıa107, J. Martin Blanco107, Y. Martynov3, A. Mas107, S. Masciocchi91, M. Masera25, A. Masoni100, L. Massacrier107, A. Mastroserio31, A. Matyja110, C. Mayer110, J. Mazer118, M.A. Mazzoni103, F. Meddi22, A. Menchaca-Rocha59, J. Mercado P´erez87, M. Meres36, Y. Miake120, K. Mikhaylov61,53, L. Milano34, J. MilosevicV,21, A. Mischke52, A.N. Mishra45, D. Mi´skowiec91, J. Mitra124, C.M. Mitu57, J. Mlynarz127, N. Mohammadi52, B. Mohanty73,124, L. Molnar50, L. Monta˜no Zetina11, E. Montes10, M. Morando28, D.A. Moreira De Godoy113, S. Moretto28, A. Morsch34, V. Muccifora66, – 19 – JHEP12(2014)073 E. Mudnic109, D. M¨uhlheim49, S. Muhuri124, M. Mukherjee124, H. M¨uller34, M.G. Munhoz113, S. Murray83, L. Musa34, J. Musinsky54, B.K. Nandi44, R. Nania99, E. Nappi98, C. Nattrass118, K. Nayak73, T.K. Nayak124, S. Nazarenko93, A. Nedosekin53, M. Nicassio91, M. Niculescu34,57, B.S. Nielsen74, S. Nikolaev94, S. Nikulin94, V. Nikulin79, B.S. Nilsen80, F. Noferini12,99, P. Nomokonov61, G. Nooren52, J. Norman117, A. Nyanin94, J. Nystrand17, H. Oeschler87, S. Oh129, S.K. OhVI,40, A. Okatan63, L. Olah128, J. Oleniacz126, A.C. Oliveira Da Silva113, J. Onderwaater91, C. Oppedisano105, A. Ortiz Velasquez32, A. Oskarsson32, J. Otwinowski91, K. Oyama87, P. Sahoo45, Y. Pachmayer87, M. Pachr37, P. Pagano29, G. Pai´c58, F. Painke39, C. Pajares16, S.K. Pal124, A. Palmeri101, D. Pant44, V. Papikyan1, G.S. Pappalardo101, P. Pareek45, W.J. Park91, S. Parmar81, A. Passfeld49, D.I. Patalakha106, V. Paticchio98, B. Paul95, T. Pawlak126, T. Peitzmann52, H. Pereira Da Costa14, E. Pereira De Oliveira Filho113, D. Peresunko94, C.E. P´erez Lara75, A. Pesci99, V. Peskov48, Y. Pestov5, V. Petr´aˇcek37, M. Petran37, M. Petris72, M. Petrovici72, C. Petta27, S. Piano104, M. Pikna36, P. Pillot107, O. Pinazza99,34, L. Pinsky115, D.B. Piyarathna115, M. P losko´n68, M. Planinic121,92, J. Pluta126, S. Pochybova128, P.L.M. Podesta-Lerma112, M.G. Poghosyan34, E.H.O. Pohjoisaho42, B. Polichtchouk106, N. Poljak92, A. Pop72, S. Porteboeuf-Houssais64, J. Porter68, B. Potukuchi84, S.K. Prasad127, R. Preghenella99,12, F. Prino105, C.A. Pruneau127, I. Pshenichnov51, G. Puddu23, P. Pujahari127, V. Punin93, J. Putschke127, H. Qvigstad21, A. Rachevski104, S. Raha4, J. Rak116, A. Rakotozafindrabe14, L. Ramello30, R. Raniwala85, S. Raniwala85, S.S. R¨as¨anen42, B.T. Rascanu48, D. Rathee81, A.W. Rauf15, V. Razazi23, K.F. Read118, J.S. Real65, K. RedlichVII,71, R.J. Reed129, A. Rehman17, P. Reichelt48, M. Reicher52, F. Reidt87,34, R. Renfordt48, A.R. Reolon66, A. Reshetin51, F. Rettig39, J.-P. Revol34, K. Reygers87, V. Riabov79, R.A. Ricci67, T. Richert32, M. Richter21, P. Riedler34, W. Riegler34, F. Riggi27, A. Rivetti105, E. Rocco52, M. Rodr´ıguez Cahuantzi2, A. Rodriguez Manso75, K. Røed21, E. Rogochaya61, S. Rohni84, D. Rohr39, D. R¨ohrich17, R. Romita76, F. Ronchetti66, L. Ronflette107, P. Rosnet64, A. Rossi34, F. Roukoutakis82, A. Roy45, C. Roy50, P. Roy95, A.J. Rubio Montero10, R. Rui24, R. Russo25, E. Ryabinkin94, Y. Ryabov79, A. Rybicki110, S. Sadovsky106, K. ˇ Safaˇr´ık34, B. Sahlmuller48, R. Sahoo45, P.K. Sahu56, J. Saini124, S. Sakai66, C.A. Salgado16, J. Salzwedel19, S. Sambyal84, V. Samsonov79, X. Sanchez Castro50, F.J. S´anchez Rodr´ıguez112, L. ˇ S´andor54, A. Sandoval59, M. Sano120, G. Santagati27, D. Sarkar124, E. Scapparone99, F. Scarlassara28, R.P. Scharenberg89, C. Schiaua72, R. Schicker87, C. Schmidt91, H.R. Schmidt33, S. Schuchmann48, J. Schukraft34, M. Schulc37, T. Schuster129, Y. Schutz107,34, K. Schwarz91, K. Schweda91, G. Scioli26, E. Scomparin105, R. Scott118, G. Segato28, J.E. Seger80, Y. Sekiguchi119, I. Selyuzhenkov91, J. Seo90, E. Serradilla10,59, A. Sevcenco57, A. Shabetai107, G. Shabratova61, R. Shahoyan34, A. Shangaraev106, N. Sharma118, S. Sharma84, K. Shigaki43, K. Shtejer25, Y. Sibiriak94, S. Siddhanta100, T. Siemiarczuk71, D. Silvermyr78, C. Silvestre65, G. Simatovic121, R. Singaraju124, R. Singh84, S. Singha124,73, V. Singhal124, B.C. Sinha124, T. Sinha95, B. Sitar36, M. Sitta30, T.B. Skaali21, K. Skjerdal17, M. Slupecki116, N. Smirnov129, R.J.M. Snellings52, C. Søgaard32, R. Soltz69, J. Song90, M. Song130, F. Soramel28, S. Sorensen118, M. Spacek37, E. Spiriti66, I. Sputowska110, M. Spyropoulou-Stassinaki82, B.K. Srivastava89, J. Stachel87, I. Stan57, G. Stefanek71, M. Steinpreis19, E. Stenlund32, G. Steyn60, J.H. Stiller87, D. Stocco107, M. Stolpovskiy106, P. Strmen36, A.A.P. Suaide113, T. Sugitate43, C. Suire46, M. Suleymanov15, R. Sultanov53, M. ˇ Sumbera77, T. Susa92, T.J.M. Symons68, A. Szabo36, A. Szanto de Toledo113, I. Szarka36, A. Szczepankiewicz34, M. Szymanski126, J. Takahashi114, M.A. Tangaro31, J.D. Tapia TakakiVIII,46, A. Tarantola Peloni48, A. Tarazona Martinez34, M.G. Tarzila72, A. Tauro34, G. Tejeda Mu˜noz2, A. Telesca34, C. Terrevoli23, J. Th¨ader91, D. Thomas52, R. Tieulent122, A.R. Timmins115, A. Toia102, V. Trubnikov3, W.H. Trzaska116, T. Tsuji119, A. Tumkin93, R. Turrisi102, T.S. Tveter21, K. Ullaland17, A. Uras122, G.L. Usai23, – 20 – JHEP12(2014)073 M. Vajzer77, M. Vala54,61, L. Valencia Palomo64, S. Vallero87, P. Vande Vyvre34, J. Van Der Maarel52, J.W. Van Hoorne34, M. van Leeuwen52, A. Vargas2, M. Vargyas116, R. Varma44, M. Vasileiou82, A. Vasiliev94, V. Vechernin123, M. Veldhoen52, A. Velure17, M. Venaruzzo24,67, E. Vercellin25, S. Vergara Lim´on2, R. Vernet8, M. Verweij127, L. Vickovic109, G. Viesti28, J. Viinikainen116, Z. Vilakazi60, O. Villalobos Baillie96, A. Vinogradov94, L. Vinogradov123, Y. Vinogradov93, T. Virgili29, Y.P. Viyogi124, A. Vodopyanov61, M.A. V¨olkl87, K. Voloshin53, S.A. Voloshin127, G. Volpe34, B. von Haller34, I. Vorobyev123, D. Vranic91,34, J. Vrl´akov´a38, B. Vulpescu64, A. Vyushin93, B. Wagner17, J. Wagner91, V. Wagner37, M. Wang7,107, Y. Wang87, D. Watanabe120, M. Weber115, J.P. Wessels49, U. Westerhoff49, J. Wiechula33, J. Wikne21, M. Wilde49, G. Wilk71, J. Wilkinson87, M.C.S. Williams99, B. Windelband87, M. Winn87, C.G. Yaldo127, Y. Yamaguchi119, H. Yang52, P. Yang7, S. Yang17, S. Yano43, S. Yasnopolskiy94, J. Yi90, Z. Yin7, I.-K. Yoo90, I. Yushmanov94, V. Zaccolo74, C. Zach37, A. Zaman15, C. Zampolli99, S. Zaporozhets61, A. Zarochentsev123, P. Z´avada55, N. Zaviyalov93, H. Zbroszczyk126, I.S. Zgura57, M. Zhalov79, H. Zhang7, X. Zhang7,68, Y. Zhang7, C. Zhao21, N. Zhigareva53, D. Zhou7, F. Zhou7, Y. Zhou52, Zhou, Zhuo17, H. Zhu7, J. Zhu7, X. Zhu7, A. Zichichi12,26, A. Zimmermann87, M.B. Zimmermann49,34, G. Zinovjev3, Y. Zoccarato122 and M. Zyzak48 IDeceased II Also at: St. Petersburg State Polytechnical University III Also at: Department of Applied Physics, Aligarh Muslim University, Aligarh, India IV Also at: M.V. Lomonosov Moscow State University, D.V. Skobeltsyn Institute of Nuclear Physics, Moscow, Russia VAlso at: University of Belgrade, Faculty of Physics and “Vinˇca” Institute of Nuclear Sciences, Belgrade, Serbia VI Permanent Address: Konkuk University, Seoul, Korea VII Also at: Institute of Theoretical Physics, University of Wroclaw, Wroclaw, Poland VIII Also at: University of Kansas, Lawrence, KS, United States 1A.I. Alikhanyan National Science Laboratory (Yerevan Physics Institute) Foundation, Yerevan, Armenia 2Benem´erita Universidad Aut´onoma de Puebla, Puebla, Mexico 3Bogolyubov Institute for Theoretical Physics, Kiev, Ukraine 4Bose Institute, Department of Physics and Centre for Astroparticle Physics and Space Science (CAPSS), Kolkata, India 5Budker Institute for Nuclear Physics, Novosibirsk, Russia 6California Polytechnic State University, San Luis Obispo, CA, United States 7Central China Normal University, Wuhan, China 8Centre de Calcul de l’IN2P3, Villeurbanne, France 9Centro de Aplicaciones Tecnol´ogicas y Desarrollo Nuclear (CEADEN), Havana, Cuba 10 Centro de Investigaciones Energ´eticas Medioambientales y Tecnol´ogicas (CIEMAT), Madrid, Spain 11 Centro de Investigaci´on y de Estudios Avanzados (CINVESTAV), Mexico City and M´erida, Mexico 12 Centro Fermi - Museo Storico della Fisica e Centro Studi e Ricerche “Enrico Fermi”, Rome, Italy 13 Chicago State University, Chicago, U.S.A. 14 Commissariat `a l’Energie Atomique, IRFU, Saclay, France 15 COMSATS Institute of Information Technology (CIIT), Islamabad, Pakistan 16 Departamento de F´ısica de Part´ıculas and IGFAE, Universidad de Santiago de Compostela, Santiago de Compostela, Spain 17 Department of Physics and Technology, University of Bergen, Bergen, Norway 18 Department of Physics, Aligarh Muslim University, Aligarh, India – 21 – JHEP12(2014)073 19 Department of Physics, Ohio State University, Columbus, OH, United States 20 Department of Physics, Sejong University, Seoul, South Korea 21 Department of Physics, University of Oslo, Oslo, Norway 22 Dipartimento di Fisica dell’Universit`a ‘La Sapienza’ and Sezione INFN Rome, Italy 23 Dipartimento di Fisica dell’Universit`a and Sezione INFN, Cagliari, Italy 24 Dipartimento di Fisica dell’Universit`a and Sezione INFN, Trieste, Italy 25 Dipartimento di Fisica dell’Universit`a and Sezione INFN, Turin, Italy 26 Dipartimento di Fisica e Astronomia dell’Universit`a and Sezione INFN, Bologna, Italy 27 Dipartimento di Fisica e Astronomia dell’Universit`a and Sezione INFN, Catania, Italy 28 Dipartimento di Fisica e Astronomia dell’Universit`a and Sezione INFN, Padova, Italy 29 Dipartimento di Fisica ‘E.R. Caianiello’ dell’Universit`a and Gruppo Collegato INFN, Salerno, Italy 30 Dipartimento di Scienze e Innovazione Tecnologica dell’Universit`a del Piemonte Orientale and Gruppo Collegato INFN, Alessandria, Italy 31 Dipartimento Interateneo di Fisica ‘M. Merlin’ and Sezione INFN, Bari, Italy 32 Division of Experimental High Energy Physics, University of Lund, Lund, Sweden 33 Eberhard Karls Universit¨at T¨ubingen, T¨ubingen, Germany 34 European Organization for Nuclear Research (CERN), Geneva, Switzerland 35 Faculty of Engineering, Bergen University College, Bergen, Norway 36 Faculty of Mathematics, Physics and Informatics, Comenius University, Bratislava, Slovakia 37 Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University in Prague, Prague, Czech Republic 38 Faculty of Science, P.J. ˇ Saf´arik University, Koˇsice, Slovakia 39 Frankfurt Institute for Advanced Studies, Johann Wolfgang Goethe-Universit¨at Frankfurt, Frankfurt, Germany 40 Gangneung-Wonju National University, Gangneung, South Korea 41 Gauhati University, Department of Physics, Guwahati, India 42 Helsinki Institute of Physics (HIP), Helsinki, Finland 43 Hiroshima University, Hiroshima, Japan 44 Indian Institute of Technology Bombay (IIT), Mumbai, India 45 Indian Institute of Technology Indore, Indore (IITI), India 46 Institut de Physique Nucl´eaire d’Orsay (IPNO), Universit´e Paris-Sud, CNRS-IN2P3, Orsay, France 47 Institut f¨ur Informatik, Johann Wolfgang Goethe-Universit¨at Frankfurt, Frankfurt, Germany 48 Institut f¨ur Kernphysik, Johann Wolfgang Goethe-Universit¨at Frankfurt, Frankfurt, Germany 49 Institut f¨ur Kernphysik, Westf¨alische Wilhelms-Universit¨at M¨unster, M¨unster, Germany 50 Institut Pluridisciplinaire Hubert Curien (IPHC), Universit´e de Strasbourg, CNRS-IN2P3, Strasbourg, France 51 Institute for Nuclear Research, Academy of Sciences, Moscow, Russia 52 Institute for Subatomic Physics of Utrecht University, Utrecht, Netherlands 53 Institute for Theoretical and Experimental Physics, Moscow, Russia 54 Institute of Experimental Physics, Slovak Academy of Sciences, Koˇsice, Slovakia 55 Institute of Physics, Academy of Sciences of the Czech Republic, Prague, Czech Republic 56 Institute of Physics, Bhubaneswar, India 57 Institute of Space Science (ISS), Bucharest, Romania 58 Instituto de Ciencias Nucleares, Universidad Nacional Aut´onoma de M´exico, Mexico City, Mexico 59 Instituto de F´ısica, Universidad Nacional Aut´onoma de M´exico, Mexico City, Mexico 60 iThemba LABS, National Research Foundation, Somerset West, South Africa 61 Joint Institute for Nuclear Research (JINR), Dubna, Russia 62 Korea Institute of Science and Technology Information, Daejeon, South Korea 63 KTO Karatay University, Konya, Turkey 64 Laboratoire de Physique Corpusculaire (LPC), Clermont Universit´e, Universit´e Blaise Pascal, CNRS-IN2P3, Clermont-Ferrand, France 65 Laboratoire de Physique Subatomique et de Cosmologie, Universit´e Grenoble-Alpes, CNRS-IN2P3, – 22 – JHEP12(2014)073 Grenoble, France 66 Laboratori Nazionali di Frascati, INFN, Frascati, Italy 67 Laboratori Nazionali di Legnaro, INFN, Legnaro, Italy 68 Lawrence Berkeley National Laboratory, Berkeley, CA, United States 69 Lawrence Livermore National Laboratory, Livermore, CA, United States 70 Moscow Engineering Physics Institute, Moscow, Russia 71 National Centre for Nuclear Studies, Warsaw, Poland 72 National Institute for Physics and Nuclear Engineering, Bucharest, Romania 73 National Institute of Science Education and Research, Bhubaneswar, India 74 Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark 75 Nikhef, National Institute for Subatomic Physics, Amsterdam, Netherlands 76 Nuclear Physics Group, STFC Daresbury Laboratory, Daresbury, United Kingdom 77 Nuclear Physics Institute, Academy of Sciences of the Czech Republic, ˇ Reˇz u Prahy, Czech Republic 78 Oak Ridge National Laboratory, Oak Ridge, TN, United States 79 Petersburg Nuclear Physics Institute, Gatchina, Russia 80 Physics Department, Creighton University, Omaha, NE, United States 81 Physics Department, Panjab University, Chandigarh, India 82 Physics Department, University of Athens, Athens, Greece 83 Physics Department, University of Cape Town, Cape Town, South Africa 84 Physics Department, University of Jammu, Jammu, India 85 Physics Department, University of Rajasthan, Jaipur, India 86 Physik Department, Technische Universit¨at M¨unchen, Munich, Germany 87 Physikalisches Institut, Ruprecht-Karls-Universit¨at Heidelberg, Heidelberg, Germany 88 Politecnico di Torino, Turin, Italy 89 Purdue University, West Lafayette, IN, United States 90 Pusan National University, Pusan, South Korea 91 Research Division and ExtreMe Matter Institute EMMI, GSI Helmholtzzentrum f¨ur Schwerionenforschung, Darmstadt, Germany 92 Rudjer Boˇskovi´c Institute, Zagreb, Croatia 93 Russian Federal Nuclear Center (VNIIEF), Sarov, Russia 94 Russian Research Centre Kurchatov Institute, Moscow, Russia 95 Saha Institute of Nuclear Physics, Kolkata, India 96 School of Physics and Astronomy, University of Birmingham, Birmingham, United Kingdom 97 Secci´on F´ısica, Departamento de Ciencias, Pontificia Universidad Cat´olica del Per´u, Lima, Peru 98 Sezione INFN, Bari, Italy 99 Sezione INFN, Bologna, Italy 100 Sezione INFN, Cagliari, Italy 101 Sezione INFN, Catania, Italy 102 Sezione INFN, Padova, Italy 103 Sezione INFN, Rome, Italy 104 Sezione INFN, Trieste, Italy 105 Sezione INFN, Turin, Italy 106 SSC IHEP of NRC Kurchatov institute, Protvino, Russia 107 SUBATECH, Ecole des Mines de Nantes, Universit´e de Nantes, CNRS-IN2P3, Nantes, France 108 Suranaree University of Technology, Nakhon Ratchasima, Thailand 109 Technical University of Split FESB, Split, Croatia 110 The Henryk Niewodniczanski Institute of Nuclear Physics, Polish Academy of Sciences, Cracow, Poland 111 The University of Texas at Austin, Physics Department, Austin, TX, U.S.A. 112 Universidad Aut´onoma de Sinaloa, Culiac´an, Mexico 113 Universidade de S˜ao Paulo (USP), S˜ao Paulo, Brazil 114 Universidade Estadual de Campinas (UNICAMP), Campinas, Brazil – 23 – JHEP12(2014)073 115 University of Houston, Houston, TX, United States 116 University of Jyv¨askyl¨a, Jyv¨askyl¨a, Finland 117 University of Liverpool, Liverpool, United Kingdom 118 University of Tennessee, Knoxville, TN, United States 119 University of Tokyo, Tokyo, Japan 120 University of Tsukuba, Tsukuba, Japan 121 University of Zagreb, Zagreb, Croatia 122 Universit´e de Lyon, Universit´e Lyon 1, CNRS/IN2P3, IPN-Lyon, Villeurbanne, France 123 V. Fock Institute for Physics, St. Petersburg State University, St. Petersburg, Russia 124 Variable Energy Cyclotron Centre, Kolkata, India 125 Vestfold University College, Tonsberg, Norway 126 Warsaw University of Technology, Warsaw, Poland 127 Wayne State University, Detroit, MI, United States 128 Wigner Research Centre for Physics, Hungarian Academy of Sciences, Budapest, Hungary 129 Yale University, New Haven, CT, United States 130 Yonsei University, Seoul, South Korea 131 Zentrum f¨ur Technologietransfer und Telekommunikation (ZTT), Fachhochschule Worms, Worms, Germany – 24 –