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논문명/저자명
Flow measurements of charged kaons in ^58^Ni+^58^Ni collisions at 1.91 AGeV / 강태임 인기도
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서울 : 고려대학교 대학원, 2011.2
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TD 530 -11-90
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139 p. ; 26 cm
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KDMT1201103141
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학위논문(박사) -- 고려대학교 대학원, 물리학, 2011.2. 지도교수: 홍병식
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Title Page

Abstract

Contents

Chapter 1. Introduction 13

1.1. Heavy-ion collisions 13

1.2. Nuclear matter 15

1.3. Collective motion, flow 19

1.4. Strange particle, kaons 22

1.5. Subthreshold kaon production 22

1.6. In-medium Modification 23

1.7. Neutron star 27

1.8. Transport models 29

1.8.1. HSD (Hadron String Dynamics) 30

1.8.2. Isospin Quantum Molecular Dynamics (IQMD) 33

Chapter 2. The FOPI experiment 37

2.1. Accelerator facility in GSI 37

2.2. FOPI detector 42

2.2.1. Magnet 44

2.2.2. In-beam START detector 44

2.2.3. Central drift chamber (CDC) 45

2.2.4. Helitron 50

2.2.5. Plastic barrel Time-of-Flight 50

2.2.6. MMRPC Time-of-Flight 51

2.2.7. Plastic Wall (PLAWA) 51

2.2.8. Zero-Degree Detector (ZDD) 52

2.3. MMRPC Time-of-Flight upgrade 53

2.4. S325 and S325e experiment 56

2.4.1. Beam and target 58

2.4.2. Trigger 59

Chapter 3. Data analysis 60

3.1. MMRPC calibration 60

3.2. Centrality estimation 67

3.3. Identification of K+ and K- mesons(이미지참조) 69

3.4. Flow Analysis 80

3.4.1. Reaction plane reconstruction 80

3.4.2. Finite multiplicity effect 82

3.4.3. Correction for reaction plane 82

3.4.4. Reaction plane flattening treatment 82

3.4.5. Flow measurements 87

Chapter 4. Experimental results 91

4.1. Directed charged kaon flow 91

4.2. Elliptic charged kaon flow 91

4.3. Differential directed flow of charged kaons 94

4.4. Differential elliptic flow of charged kaons 94

4.5. Centrality dependence of charged kaon flow 101

4.6. Centrality dependence of differential charged kaon flow 101

Chapter 5. Discussions 111

5.1. Comparision to prediction of HSD transport model 111

5.1.1. Charged kaon flow with HSD 111

5.1.2. Charged kaon differential flow with HSD 112

5.1.3. Centrality dependence of charged kaon flow with HSD 112

5.1.4. Centrality dependence of differential charged kaon flow with HSD 119

Chapter 6. Summary 126

Appendix 130

Appendix A : Strange particle, kaons 130

A.1. Parity violation 130

A.2. Time reversal violation 131

A.3. CP violation 131

A.4. CPT invariance 133

Appendix B : Kinematics 134

B.1. Laboratory and Center-of-Momentum Frames 134

B.2. Rapidity 135

Appendix C : Bethe-Bloch equation 136

Appendix D : Statistics 137

D.1. Error estimation of mean value 137

Bibliography 138

Table 2.1. The polar angular coverage of different FOPI sub-detectors. The target position is shifted by 40 cm upstream from its nominal position in experiments analyzed in this thesis. 42

Table 3.1. Cross sections and impact parameters estimation for experiment S325 and S325e. 69

Table 3.2. Cross sections and impact parameters estimation for the whole statistics. 69

Table 3.3. K+ and K- particle identification statistics for S325 and S325e experiments. The momentum cuts, S/B ratio and number of kaons are given.(이미지참조) 79

Table 3.4. Reaction plane correction factors for charged kaon flow. 83

Figure 1.1. (a) Formation of QGP at high temperature by means of relativistic nucleus-nucleus collision with a collider-type accelerator like in RHIC. (b) Formation of QGP at high baryon density by means of less energetic collisions... 14

Figure 1.2. Energy per nucleon as a function of density at temperature of 0 K. 'The Fermi gas' curve assumes no interaction apart from Pauli blocking The other curves show minima around the observed normal nuclear density.... 16

Figure 1.3. Sketch of the QCD phase diagram, temperature T vs. the baryon chemical potential μB associated with net baryon density ρB. The cross-hatched region indicates the expected phase transition between hadronic phase...(이미지참조) 17

Figure 1.4. Reaction plane defined by the impact parameter b and the beam axis. Figure shows out of plane elliptic flow corresponding SIS energy. 19

Figure 1.5. Kaon selfenergy in a density dependent quasi-particle mass. 26

Figure 1.6. Possible internal structures and compositions of four different type of compact stars. Condensed K- mesons may prevail in the interiors, hyperon stars if hyperons (Σ, Λ, Ξ, possibly in equilibrium with the Δ resonance) be-...(이미지참조) 28

Figure 1.7. The inclusive Lorentz-invariant cross section as a function of the kaon momentum in the nucleus- nucleus c.m.s, for K- mesons at θlab=0˚ for Ni + Ni at 1.85 GeV/u without including K- selfenergies in comparison to...(이미지참조) 32

Figure 1.8. K-N inelastic (solid line) and elastic (dashed line) cross section as a function of kaon laboratory momentum PK as fitted to the experimental data from. The dotted line displays the elastic K+N cross section.(이미지참조) 34

Figure 1.9. IQMD parametrization of the RMF optical potential. For details see text. 35

Figure 2.1. Schematic of acceleration facility in GSI, showing sources, UNILAC(universal linear accelerator), low and high energy experimental area, SIS synchrotron, FRS (fragment separator) and ESR (experimental storage... 38

Figure 2.2. Schematic of synchrotron in GSI, SIS18 with major parameters given. 40

Figure 2.3. Development of SIS beam intensities after the installation of an electron cooler in the SIS and new high current injector at the UNILAC. 41

Figure 2.4. Setup of the FOPI detector. All sub-detectors are labeled. The target is placed inside of the central drift chamber (CDC), indicated by xyz coordinate arrows. The whole setup has cylindrical symmetry around the beam... 43

Figure 2.5. p-CVD diamond mounted together with electronics on the PCBduring the R& D phase. 45

Figure 2.6. Illustration of Ni+Ni collision measured with the CDC in rz plane. The open red squares mark the positions of reconstructed hits. Tracks which were found and accepted by the tracking routine are labelled by the closed... 47

Figure 2.7. CDC cross section drawings. the left side is longitudinal and the right side is transversal to beam direction. The target position is shifted by 40 cm upstream from nominal position. 48

Figure 2.8. (a) Invariant mass spectrum of pπ- pairs that form a secondary vertex (solid histogram) and normalized mixed event background (dashed histogram) before subtraction....(이미지참조) 49

Figure 2.9. Photo of the MMRPC installed in the FOPI superconducting magnet; CDC is taken out of the magnet. 54

Figure 2.10. Simulated π/K separation for MMRPC ToF with different time resolution, 120 ps and 80 ps. π are shown in blue and K are in red (sum in green).... 55

Figure 2.11. Time of flight time resolution of the MMRPC with diamond START detector. The non-Gaussian tail beyond ± 3σ is ≤ 1 %. 57

Figure 3.1. The plots on the left side are correlation plots of dt and start detector timing, energy before the MMRPC calibration is applied. The plots on the right side are after the MMRPC calibration. 62

Figure 3.2. From the top, deutron, proton, π+ and π- have shown. the dashed lines are kinematic lines, p = mβγ. The proton distribution is off from its kinematic line, additional calibration process has to be applied.(이미지참조) 63

Figure 3.3. From the left to the right, π±, K±, proton and deutron. the proton peak mean value is 0.917 GeV/c which is 20 MeV off from the ideal proton mass. 64

Figure 3.4. From the top, deutron, proton, π+ and π- are shown. The dashed line is kinematic line, p = mβγ. The plot shows the MMRPC calibration that has converged properly.(이미지참조) 65

Figure 3.5. From the left to the right, π±, K±, proton and deutron. The proton mass peak mean value is 0.936 GeV/c which is only 2 MeV off from the proton mass.(이미지참조) 66

Figure 3.6. Multiplicity distributions of S325e and S325 experiment are shown. The observed difference in shape in lower multiplicities is presumably due to the slightly different trigger conditions. 68

Figure 3.7. Momentum velocity correlation plot of particles with Z = ±1. All particle species are indicated. 71

Figure 3.8. MMRPC mass vs. CDC mass correlation plot for Z = 1, K+ island is indicated by red ellipse.(이미지참조) 72

Figure 3.9. MMRPC mass vs. CDC mass correlation plot for Z = - 1, K- island is indicated by red ellipse.(이미지참조) 73

Figure 3.10. MMRPC mass for Z = 1, the peaks from left are π, K+ and proton. The number of kaons and S/B ratio are indicated.(이미지참조) 74

Figure 3.11. MMRPC mass for Z = - 1, the peaks from left are π- and K-. The number of kaons and S/B ratio are indicated.(이미지참조) 75

Figure 3.12. Geometrical acceptance of K+ with plab = 0.13, 0.2, 0.55, 0.9 GeV/c and θ = 30, 55, 110˚; plab is plotted in dot-dashed line and θ in full line. 256803 K+ are identified.(이미지참조) 77

Figure 3.13. Geometrical acceptance of K- with plab = 0.13, 0.2, 0.45, 0.7 GeV/c and θ =30, 55, 110˚; plab is plotted in dot-dashed line and θ in full line. 5454 K- are identified.(이미지참조) 78

Figure 3.14. Schematic picture of the distribution of Q. The details are given in text. 81

Figure 3.15. Uncorrected reaction plane distribution in Φ before flattening. 84

Figure 3.16. Corrected reaction plane distribution in Φ after flattening. 85

Figure 3.17. Parameters for correction up to 4th order of Fourier expansion. 86

Figure 3.18. K+ v₁ with (blue) and without (red) reaction plane flattening correction.(이미지참조) 88

Figure 3.19. The four major types of azimuthal anisotropies, viewed in the transverse plane. The target is denoted by T and the projectile by P. Top. Directed in the projectile rapidity region, positive (left) and negative (right).... 89

Figure 3.20. 2-dimensional v₁ vs. rapidity, upper part of the plot are for proton and lower part are for K+.(이미지참조) 90

Figure 4.1. K+ directed flow in red, proton in black. K+ are identified in Prpc 〈0.9 GeV/c and Pbar 〈0.55 GeV/c.(이미지참조) 92

Figure 4.2. K- directed flow in blue. K- are identified in Prpc 〈0.7 GeV/cand Pbar 〈0.45 GeV/c.(이미지참조) 93

Figure 4.3. K+ elliptic flow in red. K+ are identified in Prpc〈0.9 GeV/c and Pbar 〈0.55 GeV/c.(이미지참조) 95

Figure 4.4. K- elliptic flow in blue. K- are identified in Prpc 〈0.7 GeV/c and Pbar 〈0.45 GeV/c.(이미지참조) 96

Figure 4.5. K+ differential directed flow in red within rapidity range -1.3 〈y0 〈-0.5. K+ are identified in Prpc 〈0.9 GeV/c and Pbar 〈0.55 GeV/c.(이미지참조) 97

Figure 4.6. K+ differential directed flow in red within rapidity range -0.5 〈y0 〈-0.2. K+ are identified in Prpc 〈0.9 GeV/c and Pbar 〈0.55 GeV/c.(이미지참조) 98

Figure 4.7. K- directed flow as a function of pT differential directed flow in blue within rapidity range -1.3 〈y0 〈-0.5. K- are identified in Prpc 〈0.7 GeV/c and Pbar 〈0.45 GeV/c.(이미지참조) 99

Figure 4.8. K- differential directed flow as a function of pT differential directed flow in blue within rapidity range -0.5 〈y0 〈-0.2. K- are identified in Prpc 〈0.7 GeV/c and Pbar 〈0.45 GeV/c.(이미지참조) 100

Figure 4.9. K+ differential elliptic flow in red within rapidity range -1.3〈y0 〈-0.5. K+ are identified in Prpc 〈0.9 GeV/c and Pbar 〈0.55 GeV/c.(이미지참조) 102

Figure 4.10. K+ differential elliptic flow in red within rapidity range -0.5 〈y0 〈-0.2. K+ are identified in Prpc 〈0.9GeV/c and Pbar 〈0.55 GeV/c.(이미지참조) 103

Figure 4.11. K+ directed flow in blue. K+ are identified in Prpc 〈0.9 GeV/c and Pbar 〈0.55 GeV/c.(이미지참조) 104

Figure 4.12. K+ elliptic flow in blue K+ are identified in Prpc 〈0.9 GeV/c and Pbar 〈0.5 GeV/c.(이미지참조) 105

Figure 4.13. K- directed flow in blue.K- are identified in Prpc 〈0.7 GeV/c and Pbar 〈0.45 GeV/c.(이미지참조) 106

Figure 4.14. K+ differential directed flow as a function of pT. differential directed flow in blue within rapidity range -0.3 〈y0 〈-0.5. K+ are identified in Prpc 〈0.9 GeV/c and Pbar 〈0.55 GeV/c.(이미지참조) 108

Figure 4.15. K+ differential directed flow as a function of pT differential directed flow in blue within rapidity range -0.5 〈y0 〈-0.2. K+ are identified in Prpc 〈0.9 GeV/c and Pbar 〈0.55 GeV/c.(이미지참조) 109

Figure 4.16. K+ differential directed flow as a function of pT differential directed flow in blue. within rapidity range -0.3 〈y0 〈-0.5. K- are identified in Prpc 〈0.7 GeV/c and Pbar 〈0.45 GeV/c.(이미지참조) 110

Figure 5.1. K+ directed flow with HSD calculations. The circle points are data point and the bands are HSD calculation. The red band is with 20 MeV K+N potential while the sky blue band is without K+N potential.(이미지참조) 113

Figure 5.2. K+ elliptic flow with HSD calculations. The circle points are data point and the bands are HSD calculation. The red band is with 20 MeV K+N potential while the sky blue band is without K+N potential.(이미지참조) 114

Figure 5.3. K- directed flow with HSD calculations. The circle points are data point and the bands are HSD calculation. The blue band is with -100 MeV K-N potential while the sky blue band is without K-N potential.(이미지참조) 115

Figure 5.4. K- elliptic flow with HSD calculations. The circle points are data point and the bands are HSD calculation. The blue band is with -100 MeV K-N potential while the sky blue band is without K-N potential.(이미지참조) 116

Figure 5.5. K+ differential directed flow with HSD calculations. The circle points are data point and the bands are HSD calculation. The red band is with 20 MeV K+N potential while the sky blue band is with out K+N potential.(이미지참조) 117

Figure 5.6. K- differential directed flow with HSD calculations. The circle points are data point and the bands are HSD calculation. The blue band is with -100 MeV K-N potential while the sky blue band is without K+N potential.(이미지참조) 118

Figure 5.7. Centrality dependence of K+ directed flow with HSD calculations. The circular points are for peripheral collisions, 3 〈b 〈7 fm, and the triangular points are for central collisions, 0 〈b 〈3 fm....(이미지참조) 120

Figure 5.8. Centrality dependence of K+ elliptic flow with HSD calculations. The circular points are for peripheral collisions, 3 〈b 〈7 fm, and the triangular points are for central collisions, 0 〈b3 fm....(이미지참조) 121

Figure 5.9. Centrality dependence of K- directed flow with HSD calculations. The circular points are for peripheral collisions, 3 〈b 〈7 fm, and the triangular points are for central collisions, 0 〈b 〈3 fm....(이미지참조) 122

Figure 5.10. Centrality dependence of K- elliptic flow with HSD calculations. The circular points are for peripheral collisions, 3 〈b 〈7 fm, and the triangular points are for central collisions, 0 〈b 〈3 fm....(이미지참조) 123

Figure 5.11. Centrality dependence of K+ differential directed flow with HSD calculations. The circular points are for peripheral collisions, 3 〈b 〈7 fm, and the triangular points are for central collisions, 0 〈b 〈3 fm....(이미지참조) 124

Figure 5.12. Centrality dependence of K- differential directed flow with HSD calculations. The circular points are for peripheral collisions, 3 〈b 〈7 fm, and the triangular points are for central collisions, 0 〈b 〈3 fm....(이미지참조) 125

참고문헌 (71건) : 자료제공( 네이버학술정보 )더보기

참고문헌 목록에 대한 테이블로 번호, 참고문헌, 국회도서관 소장유무로 구성되어 있습니다.
번호 참고문헌 국회도서관 소장유무
1 Kaon Flow as a Probe of the Kaon Potential in Nuclear Medium 네이버 미소장
2 “Subatomic physics”, World scientific publishing (2007). 미소장
3 Equation of state of nucleon matter and neutron star structure 네이버 미소장
4 Nuclear Physics Needed for the Theory of Supernovae 네이버 미소장
5 Incompressibility of Nuclear Matter from the Giant Monopole Resonance 네이버 미소장
6 “Hardronic Matter is Soft”, Rhys. Rev. Lett 96, 012302 (2006). 미소장
7 “The Little Bang: Searching for quark-gluon matter in relativistic heavy-ion collisions”, arXiv:hep-ph/0009170v2 (2000). 미소장
8 Radial Flow in Au + Au Collisions at E = (0.25-1.15)A GeV 네이버 미소장
9 Methods for analyzing anisotropic flow in relativistic nuclear collisions 네이버 미소장
10 Flow systematics from SIS to SPS energies 네이버 미소장
11 Transverse momentum analysis of collective motion in relativistic nuclear collisions 네이버 미소장
12 Collective Flow Observed in Relativistic Nuclear Collisions 네이버 미소장
13 Momentum-dependent nuclear mean fields and collective flow in heavy-ion collisions. 네이버 미소장
14 Nuclear Collective Flow as a Function of Projectile Energy and Mass 네이버 미소장
15 Azimuthal anisotropies as stringent test for nuclear transport models 네이버 미소장
16 Kaons in baryonic matter 네이버 미소장
17 “Reconstructing azimuthal distribution in nucleus-nucleus collisions”, nucl-ex/9711003 (1997). 미소장
18 “Dynamics of K+ Production in Heavy Ion Collisions close to Threshold”, nucl-th/0507002. 미소장
19 “Strangelets and Strange Quark Matter”, nuclth/9711044v1 (1997). 미소장
20 Many-body theory of high-energy heavy-ion reactions 네이버 미소장
21 Analysis of kaon production at SIS energies 네이버 미소장
22 “Transport Theories for Heavy Ion Collisions in the 1 AGeV Regime”, arXiv:nucl-th/0412037v2. 미소장
23 Production of energetic particles in heavy-ion collisions 네이버 미소장
24 Production of K + and of K − mesons in heavy-ion collisions from 0.6 A to 2.0 A GeV incident energy 네이버 미소장
25 Review of SIS experimental results on strangeness 네이버 미소장
26 Study of high-energy heavy-ion collisions in a relativistic BUU approach with momentum-dependent mean fields 네이버 미소장
27 Strange goings on in dense nucleonic matter 네이버 미소장
28 Strange condensate realignment in relativistic heavy ion collisions 네이버 미소장
29 “Scaling Effective Lagrangians in a Dense Medium”, Phys. Rev. Lett. 66 (1991) 2720 미소장
30 Quark condensate in nuclear matter 네이버 미소장
31 Kaons in baryonic matter 네이버 미소장
32 Low energy [formula omitted]N interaction in nuclear matter 네이버 미소장
33 Effective kaon masses in dense nuclear and neutron matter 네이버 미소장
34 Kaon condensation in nuclear matter 네이버 미소장
35 Kaon modification in hot hadronic matter 네이버 미소장
36 Kaon versus antikaon production at SIS energies 네이버 미소장
37 “Quark-Gluon Plasma ”, Cambridge University Press 2005. 미소장
38 “Strange quark matter adn compact stars ”, astro-ph/0407155 (2004). 미소장
39 Antikaon production in A+ A collisions at SIS energies within an off-shell G-matrix approach 네이버 미소장
40 In-medium kaon production at the mean-field level 네이버 미소장
41 Subthreshold antiproton production in heavy ion collisions 네이버 미소장
42 “Resonance model of πΔ → YK for kaon production in heavy-ion collisions”, Phys. Lett. B 337 (1994) 245. 미소장
43 “Production of K−mesons in proton-proton and proton-nucleus interactions at various energies”, Z. Phys. A 348 (1994) 217. 미소장
44 “Strangeness production in antiproton annihilation on nuclei”, Phys. Rev. C 41 (1990) 1701. 미소장
45 The “subthreshold” production of antikaons in relativistic nuclear collisions 네이버 미소장
46 FOPI official website, www-fopi.gsi.de 미소장
47 High intensity developments at GSI 네이버 미소장
48 The FOPI detector at SIS/GSI 네이버 미소장
49 M. Kiš et al., FOPI Collaboration, “A diamond start detector for FOPI”, GSI Sci. Rep. 2005 269. 미소장
50 M. Kiš et al., FOPI Collaboration, “p-CVD diamond heavy-ion beam detectro with integrated electronics”, GSI Sci. Rep. 245 (2008). 미소장
51 M. Merschmeyer et al., FOPI Collaboration, “Production and Flow of Neutral Strange Particles in Ni+Ni Collisions at 1.93 AGeV”, Ph.... 미소장
52 A highly-segmented ΔE-time-of-flight wall as forward detector of the 4π-system for charged particles at the SIS/ESR accelerator 네이버 미소장
53 Timing RPCs in FOPI 네이버 미소장
54 Performance of the Multistrip-MRPCs for FOPI 네이버 미소장
55 Multi-strip MRPCs for FOPI 네이버 미소장
56 M. Kiš et al., FOPI Collaboration, “A Multi-Strip Multi-Gap RPC Barrel for Time-of-Flight Measurements”, Submitted to Nucl. Instr.... 미소장
57 “A Front-End Electronics Card Comprising a high Gain/High Bandwidth Amplifier and a Fast Discriminator for Time-of-Flight... 미소장
58 “A new TAC-based multichannel front-end electronics for TOF experiments with very high time resolution”, IEEE Trans. Nucl. Sci.... 미소장
59 Central collisions of relativistic heavy ions 네이버 미소장
60 Determination of the impact parameter in relativistic nucleus-nucleus collisions. 네이버 미소장
61 J.Barrette et al., E877 Colaboration, “Proton and Pion Production Relative to the Reaction Plane in Au + Au Collisions at AGS... 미소장
62 Sideward flow of K + mesons in Ru+Ru and Ni+Ni reactions near threshold 네이버 미소장
63 Discussions in FOPI collaboration meeting in M¨unchen in May 2010. 미소장
64 Question of Parity Conservation in Weak Interactions 네이버 미소장
65 Experimental Test of Parity Conservation in Beta Decay 네이버 미소장
66 First direct observation of time-reversal non-invariance in the neutral-kaon system 네이버 미소장
67 “WHAT DO WE KNOW ABOUT TIME REVERSAL INVARIANCE VIOLATION”, Fizika B10, 161 (2001). 미소장
68 Behavior of Neutral Particles under Charge Conjugation 네이버 미소장
69 Evidence for the 2 π Decay of the K 2 0 Meson 네이버 미소장
70 Search for CP nonconservation in K 2 0 decays 네이버 미소장
71 Time Reversal and the K 0 Meson Decays 네이버 미소장

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