Title Page
Contents
ABSTRACT 18
Chapter 1. Introduction 19
Chapter 2. Heavy Quarkonia and the QGP 21
2.1. Strong interaction and QCD phase transition 21
2.2. Dynamical evolution of a heavy-ion collision in space-time 26
2.3. Observables to probe the QGP 27
2.4. Heavy quarkonium as a probe of the QGP 29
2.4.1. The discovery of heavy quarkonia 29
2.4.2. The characteristic of heavy quarkonium 32
2.4.3. Heavy quarkonium in hot medium 34
2.4.4. Cold-Nuclear-Matter effects 35
2.4.5. Experimental results of heavy quarkonium suppression 36
2.5. Production mechanisms of heavy quarkonia 39
Chapter 3. ALICE Detectors 45
3.1. Central Detectors 47
3.1.1. Inner Tracking System 47
3.1.2. Time-Projection Chamber 49
3.1.3. Transition-Radiation Detector 50
3.1.4. Time-Of-Flight Detector 51
3.1.5. High-Momentum Particle Identi cation Detector 52
3.1.6. Photon Spectrometer 54
3.1.7. Electromagnetic Calorimeter 54
3.1.8. ALICE Cosmic Ray Detector 56
3.2. Forward Detectors 56
3.2.1. Zero Degree Calorimeter 57
3.2.2. Photon Multiplicity Detector 57
3.2.3. Forward Multiplicity Detector 57
3.2.4. V0 Detector 61
3.2.5. T0 Detector 62
3.3. Muon Spectrometer 62
3.3.1. Absorbers and dipole magnet 64
3.3.2. Tracking system 66
3.3.3. Trigger system 70
3.4. The ALICE off-line framework 74
3.4.1. Correction framework 79
3.4.2. Dedicated classes for Υ analysis(이미지참조) 83
Chapter 4. OnlineDQMfor Muon Trigger 88
4.1. Interactive Data Quality Monitoring: MOOD 89
4.2. Automatic Data Quality Monitoring: AMORE 92
4.3. Development of Online DQM software for Muon Trigger 95
4.3.1. Payload decoder 97
4.3.2. Monitoring Objects 104
Chapter 5. Data Analysis 111
5.1. Monte Carlo based analysis: PDC09 113
5.1.1. Signal Extraction 113
5.1.2. 〈A×∈〉 Correction 118
5.2. Expectation for Υ states(이미지참조) 127
5.3. Υ Production Cross Section Estimation(이미지참조) 130
5.3.1. Method 130
5.3.2. Data selection 133
5.3.3. Event selection 134
5.3.4. Extracting signals 135
5.3.5. 〈A×∈〉 Estimation 138
5.3.6. Results 140
Chapter 6. Conclusion 147
References 150
Appendices 7
Appendix A. ALICE coordinate system 159
Appendix B. Kinematic variables 161
Appendix C. Error propagation 162
Appendix D. Glossary 163
국문초록 166
Table 2.1: Upper bounds on the dissociation temperatures. 35
Table 3.1: A summary of the detector parameters of the central detectors. 48
Table 3.2: A summary of the detector parameters of the forward detectors. 60
Table 5.1: The mass and branching ratio of the charmonium, J/Ψ and bot-tomoniumstates, Y(nS) quoted from the Particle Data Group (PDG).(이미지참조) 112
Table 5.2: A summary table about the definition of the distribution functions used in the analysis. G■L represents the normalized Gaussian convoluted with Landau function (an approximate analytic form).(이미지참조) 115
Table 5.3: The summary of the fit results of three different fit functions used in the fit to simulated Y(1S) signal shown in Fig. 5.2.(이미지참조) 117
Table 5.4: The summary of fit results of the global fit shown in Fig. 5.3. 117
Table 5.5: A summary table of NY(1S) obtained from Fig. 5.4. Numbers in parentheses are the number of generated Y(1S).(이미지참조) 120
Table 5.6: The number of generated Y with two different configurations in the pt range [0; 20 (GeV/c)].(이미지참조) 122
Table 5.7: The integrated acceptance times efficiency of Y → μ+μ- in the ALICE muon spectrometer obtained from different simulations: in pp colli-sions at √s=10TeV energy (produced for the PDC09 analysis) and in pp collisions at √s=14TeV energy (the result of ALICE Physics Performance...(이미지참조) 125
Table 5.8: A summary of the predicted production cross section of Y states including direct and feedback in pp collisions at √s=7TeV and the estimation of the expected number of Y(nS) produced for L=1pb-¹.(이미지참조) 128
Table 5.9: Fit results of the predicted μ+μ- mass spectrum for L=1pb-¹ shown in Fig. 5.11. S/B and Significance were alculated in the range [Mean-2σ; Mean+2σ](이미지참조) 130
Table 5.10: Event statistics of LHC10g period for qualified runs taken from the Run Condition Table [4]. The total/analyzed number of events be-fore/after applying physics selection and the number of μ+μ- pair events analyzed in this analysis are shown. Note that the time sharing during this...(이미지참조) 134
Table 5.11: The summary of parameters for fitting to J/ψ and Υ mass dis-tributions. The ratio of S (signal) and B (background), and significance of the signal are obtained in the range [Mean-2σ; Mean+2σ](이미지참조) 138
Table 5.12: The extracted NY(1S+2S+3S) from the invariant mass distribu-tionswith different binnings.(이미지참조) 138
Table 5.13: The acceptance times efficiency of J/Ψ with different pt-trigger cut combinations obtained by realistic sim-ulation for each run in LHC10g period.(이미지참조) 143
Table 5.14: The acceptance times efficiency of Υ(1S) with different pttrigger cut combinations obtained by realistic simulation foreach run in LHC10g period.(이미지참조) 144
Figure 2.1: The fundamental form of quark-gluon interaction. The color charge is exchanged at the vertex. 22
Figure 2.2: Sketch of the QCD matter phase diagram in the plane of temper-ature T and baryo-chemical potential μB. The parton-hadron phase transi-tion line from lattice QCD ends in a critical point E. A cross-over transition occurs at smaller μB (see [5] and references therein).(이미지참조) 25
Figure 2.3: Schematic light cone diagram of the evolution of a high energy heavy-ion collision, indicating a QGP formation time T0 [5] (see text).(이미지참조) 26
Figure 2.4: Mass spectrum showing the existence of J/Ψ meson reported by(a) BNL [6] and (b) SLAC [7]. 30
Figure 2.5: Measured di-muon production cross section as a function of the invariant mass of the muon pair [8]. The closed circles are data points of unlike sign muon pair and the open circles are that of like sign muon pair. The solid line is the continuum fit. 31
Figure 2.6: The strong coupling constant, αs, as a function of quarko-nium radius r, with labels indication approximate values of mQv for Υ(1S), J/ψ, and Υ(2S) [9].(이미지참조) 33
Figure 2.7: Static QQ potential as a function of quarkonium radius r [9].(이미지참조) 34
Figure 2.8: The EPS09 gluon-shadowing parameterization [10] at Q=2mc and mb. The central value (solid curves) and the associated uncertainty (shaded band) are shown. 36
Figure 2.9: The J/Ψ/Drell-Yan cross-sections ratio vs. L (see text) for several collision systems divided by the nuclear absorption pattern [11]. 37
Figure 2.10: J/ψ suppression pattern in In-In (circles) and Pb-Pb (triangles) as a function of Npart. Boxes around the points correspond to the correlated systematic errors, while the filled box on the right corresponds to the un-certainty on the absolute normalization of In-In points [12].(이미지참조) 38
Figure 2.12: The leading-order QCD processes 40
Figure 2.13: Comparison between preliminary measurements from CDF for J/ψ and the various models, CSM (dotted curves), CEM (dashed curves), and NRQCD (solid curves) [9]. The CSM fragmentation contribution is also shown [14] 41
Figure 2.14: pt dependence of Υ(1S) production cross section measured by CDF and the comparison with CSM NLO and NNLO* [15].(이미지참조) 42
Figure 2.15: (a) Polarization of prompt J/Ψ as a function of pt measured by CDF (blue points with black error bars). The blue band (magenta line) is the prediction from NRQCD [16] (the kT factorization model [17]). (b) Polarization of inclusive Y(1S) as functions of pt measured by CDF (green)...(이미지참조) 44
Figure 3.1: A schematic 3D view of the ALICE detector [19]. 46
Figure 3.2: Layout of Inner Tracking System. 49
Figure 3.3: A 3D view of TPC field cage and service support wheels. 50
Figure 3.4: A dE/dx spectrum versus momentum of TPC in pp collisions at √s=7TeV. The lines are a parameterization of the Bethe-Bloch curve.(이미지참조) 51
Figure 3.5: A schematic 3D drawing of TRD layout in the ALICE space frame. 52
Figure 3.6: Particle identification of TOF via measured particle β(= v/c) versus momentum in pp collisions at √s=7TeV.(이미지참조) 53
Figure 3.7: A schematic drawing of one TOF super-module in the ALICE space frame. 53
Figure 3.8: View of modules of HMPID mounted on the cradle. 54
Figure 3.9: View of modules of PHOS. 55
Figure 3.10: Schematic integration drawing of the end view of the ALICE central barrel. 55
Figure 3.11: Photograph of ACORDE scintillator modules on the upper faces of the magnet yoke of ALICE. 56
Figure 3.12: Simulated pseudo-rapidity coverage of FMD rings (1 inner, 2 inner and outer, and 3 inner and outer) along with two SPD layers. The multiplicity distribution is produced by (a) PYTHIA [20] in pp collisions at √/s=14TeV; (b) HIJING [21, 22] in Pb-Pb collisions at√snn=5.5TeV.(이미지참조) 58
Figure 3.13: V0 amplitude distribution split in event centralities determined by ZDC: 0-5%, 5-10%, 10-20%, and 20-30%. 59
Figure 3.14: Schematic top view of the side of ALICE beam line opposite to the muon arm. The locations of the neutron (ZN), proton (ZP) and elec-tromagnetic calorimeters (ZEM) are shown. 59
Figure 3.15: Layout of FMD rings. FMD3 and FMD2 are located on each side of ITS; FMD1 is much further away from IP. 61
Figure 3.16: Layout of T0 detectors. 63
Figure 3.17: Muon spectrometer longitudinal section 63
Figure 3.18: (a) Graphite and (b) steel envelope for the front absorber 64
Figure 3.19: View of the muonlter (left) and dipole magnet (right). 66
Figure 3.20: View of two kinds of tracking station: (a) station 2 (quadrant type); (b) stations 4 and 5 (slat type). 68
Figure 3.21: General view of the GMS setup. The lines on this figure rep-resent the optical lines. 70
Figure 3.22: View of the two trigger stations. 71
Figure 3.23: Map of the trigger zones boards as seen from the interaction point. 73
Figure 3.24: The schematic longitudinal view of the muon spectrometer. The track deviation relative to a particle with infinite momentum is computed and then the deviation cut performed by means of look-up tables. 74
Figure 3.25: The schematic view of the trigger electronics. 75
Figure 3.26: Schematic view of the AliRoot framework. 76
Figure 3.27: Geometry of the ALICE detector in the AliRoot simulation. 77
Figure 3.28: Interaction of the reconstruction code with the other parts of AilRoot. 78
Figure 3.29: The general scheme of the container classes of the Correction framework. 80
Figure 3.30: A typical flow of the correction process. 82
Figure 3.31: The (a) pt and (b) rapidity distribution of simulated Y(1S) and corresponding reconstruction efficiency obtained from ESD type data.(이미지참조) 85
Figure 3.32: The (a) pt and (b) rapidity distribution of simulated Y(1S) and corresponding reconstruction efficiency obtained from AOD type data.(이미지참조) 86
Figure 4.1: Example of MOOD screen view. 91
Figure 4.2: The comparison between the features of MOOD and AMORE. 93
Figure 4.3: Publish-subscribe scheme of AMORE. 93
Figure 4.4: An example view of (a) hit multiplicity panel and (b) trigger algorithm panel of MOOD expert version. There is a missing column in both figures due to the problem with a regional trigger board. A mal-functioning local trigger board can be found in (b). 96
Figure 4.5: A general scheme of AMORE modules for trigger system. Green-coloredboxes represent the publish process while green-colored boxes repre-sent the subscribe process. Yellow-colored box indicates the raw data flow from the detector. amoreAgentMTR01 is a amoreAgent responsible for pub-lishing...(이미지참조) 98
Figure 4.6: Example view of the shift version of (a) MOOD and (b) AMORE. 99
Figure 4.7: Schematic view of the DDL raw event for trigger chambers. 101
Figure 4.8: Example screen view of raw data structure of MOOD implemen-tationfor the shift version. The event type of this example is figured out physics run (top-left), and therefore the size of DDL is 824 (bottom). Some of End of Words errors are shown (top-right). 105
Figure 4.9: Example plots of raw data structure of AMORE implementa-tion. The green bars indicates the purity of the raw data structure at each electronic level. From the left to the right, DARC, Global, Regional and Lo-cal board. (a) No corruption is showed in the left panel. (b) In the right... 106
Figure 4.10: Example screen view ofred strip multiplicities with MOOD shift module. 107
Figure 4.11: Example plots of fired trigger boards with AMORE shift mod-ule. (a) The multiplicities of each trigger boards are 6 for global board, 16 for regional boards, 234 for local boards and 20992 for strips (from left). (b) The zoomed-in view of the strip multiplicity shows thatuctuation of... 108
Figure 4.12: Example plot of the trigger effciency 44/34 as a function of time implemented in AMORE shift module. The green line is the ratio for physics run over time (in minutes) and the red line indicates the overall average of the ratio at the given time which looks become stable as time... 109
Figure 4.13: Example plots of global trigger output of MOOD implementation (left) and AMORE implementation (right). The white bar (left) and grey bar (right) represent the single muon choice which not transferred to CTP. For AMORE, red bar will be shown up if there is any errors of global... 110
Figure 4.14: Example plots of global scaler shown in MOOD (left) and AMORE (right) for calibration run. The red line represents global scalers read-out during calibration event and the green bars represent global output of calbration run. 110
Figure 5.1: The μ+μ- invariant mass distribution of PDC09 production in the mass range [0; 15 (GeV/c²)] with logarithmic scaled Y-axis. 114
Figure 5.2: The μ+μ- invariant mass distribution (with logarithmic scaled Y-axis) of simulated Y with the three different fits: mainly (a) Gaussian, (b) Crystal Ball and (c) Gaussian convoluted with Landau functions. In order to reproduce tails additional Gaussian functions are cumulated. Each fit gives...(이미지참조) 116
Figure 5.3: The μ+μ- invariant mass distribution of PDC09 production (with logarithmic scaled Y-axis) with the global fit in the mass range [7; 12 (GeV/c²)].(이미지참조) 118
Figure 5.4: The μ+μ- invariant mass distributions in mass range [7; 12 (GeV/c²)] with different pt and rapidity range. The intervals of pt range are 2 GeV/c in [0; 10 (GeV/c)] and 5 GeV/c up to 20 GeV/c. Rapidity interval is 0.3.(이미지참조) 119
Figure 5.5: (a) pt- and (b) rapidity-dependence of NY(1S) for PDC09 produc-tion. Black square points represent the distribution of dN/dy or dN/dpt of Y(1S) at the generation level; cyan triangle points represent those of Y(1S) at the reconstruction level.(이미지참조) 121
Figure 5.6: The effect of the distribution of z-component of a primary vertex, σVz, on the mass resolution in the simulation. The case (a) σVz=5.3cm shows that the mass resolution of Y is 149.1 MeV/c², while (b) σVz=0cm shows that the mass resolution is 83 MeV/c². The mass resolution of Y in...(이미지참조) 124
Figure 5.7: pt- and rapidity-differential acceptance times efficiency obtained from y-cut data set to be used for the correction on the dNY(1S)/dy and dNY(1S)/dpt of PDC09 production (see Fig. 5.5).(이미지참조) 126
Figure 5.8: (a) pt and (b) rapidity distribution of Y of PDC09 production after correction (red marker).(이미지참조) 127
Figure 5.9: The μ+μ- invariant mass distribution of Y states, Y(1S) (green), Y(2S) (cyan), and Y(3S) (red) of the simulation with current mis-alignment. The resonances are not separable due to the worse mass resolution, ~230MeV=c².(이미지참조) 129
Figure 5.10: The μ+μ- continuum of (a) LHC10e and (b) MC random gen-eration from LHC10e continuum. Double exponential function (red curve) is used tot to the LHC10e continuum in mass range [4; 15 (GeV/c²)]. MC continuum is produced by a fast simulation from the LHC10e continuum.(이미지참조) 131
Figure 5.11: An expected μ+μ- mass spectrum for L=1 pb-¹. This is obtained from the combined spectrum of Y(1S+2S+3S) and MC continuum from LHC10e. Double exponential function and Gaussian function are used tot to the spectrum.(이미지참조) 132
Figure 5.12: The reconstructed μ+μ- pairs of J/Ψ and Y simulation with different pt trigger cuts: (0, 0) and (Hpt, Hpt). Hpt represents ptμ〉1 GeV/c. The survival rates with respect to (Hpt, Hpt) for each resonance are: (a)~59% for J/Ψ and (b)~90% for Y.(이미지참조) 135
Figure 5.13: A schematic view of muon spectrometer together with muon tracks traversing within its geometrical acceptance and Rabs as well.(이미지참조) 136
Figure 5.14: The invariant mass distributions in the (a) J/Ψ and (b) Y mass region, [2; 5(GeV/c²)] and [7; 12(GeV/c²)], respectively. The fit parameters are summarized in Tab. 5.11(이미지참조) 137
Figure 5.15: The invariant mass distribution of Y(1S+2S+3S) with different number of bins: (a) 60, (b) 75, (c) 100, and (d) 150 bins. They shows the consistent number of signal for Y(1S + 2S + 3S) within the errors.(이미지참조) 139
Figure 5.16: The acceptance times effciency as a function of run in LHC10g period for (a) J/Ψ and (b) Y(1S). The effects of pt trigger cut combinations are presented: (0, 0), (Lpt, 0), (Lpt, Lpt), (Hpt, 0), (Hpt, Lpt), and (Hpt, Hpt). "Lpt" represents the low pt trigger cut (pt〉0.5GeV/c) and "Hpt"(이미지참조) 141
Figure 5.17: The ratio of (A×Ε)J/Ψ and (A×Ε)Y(1S) as a function of run in LHC10g. Showing a consistent trend versus runs is important because this means that we can safely use the average value of the acceptance times efficiency in the calculation of the Y(nS) production cross section.(이미지참조) 142
Figure 5.18: The rapidity-differential production cross section of Y(1S) mea-sured in pp collisions at √s=7TeV. The data points of CMS (corre-sponding integrated luminosity L=3pb-¹) and LHCb (corresponding in-tegrated luminosity L=32.4 pb-¹) are described by green triangles and...(이미지참조) 146
Figure 6.1: A performance plot for Y signal. The analysis is done with a portion of data taken in 2011.(이미지참조) 149
List of Appendixs Figures
Figure A.1: The ALICE coordination system. 160