Study of the Multi-strange Resonance Ξ(1530)0 Production with ALICE at the LHC Energies = 대형강입자충돌기 (LHC)의 대형이온충돌기 실험 (ALICE)에서 측정된 크시(Ξ(1530)0) 공명입자 생성 연구

국문 초록 (Abstract)

대형강입자충돌기 (Large Hadron Collider: LHC)에서 진행되는 초상대론적 중이온충돌 을통해초고온, 고압상태의물질을생성할수있다. 극한상태물질의특성을연구하기 위해 다양한 수명을 갖는 강입자들을 재구성 한다. 이를 통해서 쿼크물질과 강입자들의 상호작용 – 재산란 및 재생성 – 을 유추해볼 수 있다.
본 논문에서는 강입자 분석에 사용된 대형이온충돌기 실험 (A Large Ion Collider Experiment: ALICE)에 대해 설명하고, ALICE를 통한 입자 확인 방법에 대해서 논의한다.
다양한 수명을 갖는 강입자 중 본 논문에서는 크시 입자를 분석 하였다. 크시입자의 가로운동량 분포를 측정하였고, 그 분포를 통해 크시입자의 생성량과 평균가로운동량을 충돌 시스템에 대해 분석하였다.
본 논문에서는 여러 충돌 시스템으로부터 생성된 크시 입자와 긴수명을 갖는 입자들의 상대적인 생성량및 평균가로운동량에 대해 논의 할 것이다.

다국어 초록 (Multilingual Abstract)

The primary goal of the relativistic heavy-ion physics program at Large Hadron Collider (LHC) at CERN, Geneva, Switzerland is to study the nuclear matter under extreme conditions. The measurement of resonances in ultra-relativistic heavy-ion collisions allows one to study the properties of the hadronic medium. Resonances with short lifetimes compared to the duration of the time span between chemical and kinetic freeze-out are good candidates to prove the interplay of particle re-scattering and regeneration in the hadronic phase, which result in a modification of their measured yields.
The ALICE detector and its subsystem used for the analysis presented in this thesis are explained. Particle identification method and a coordinate system of ALICE are provided.
Measurements of multi-strange resonance Ξ(1530)0 were performed with the ALICE detector in pp, p-Pb and Pb-Pb collisions at the LHC energies.
The pT-spectra of Ξ(1530)0 are obtained and compared with model predictions. The yield ratios of Ξ(1530)0 to stable hadrons are shown and discussed. Mean transverse momentum of Ξ(1530)0 has been investigated and compared with that of identified hadrons. The comparison of results obtained for other resonances is also presented in this thesis.

목차 (Table of Contents)

• Chapter 1 Introduction 1
• 1.1 Matter under extreme conditions 1
• 1.2 Collision systems and physical observables in experiment 4
• 1.3 Resonance and hyperon production 6
• 1.3.1 Study of hadronic phase 6
• 1.3.2 Hyperon production 10
• 1.3.3 Mean transverse momentum 12
• Chapter 2 A Large Ion Collider Experiment at the LHC 14
• 2.1 The ALICE detector 15
• 2.1.1 Particle identification in the TPC 19
• 2.1.2 Particle identification using weak decay topology 22
• 2.1.3 Definition of ALICE coordinate system 23
• 2.2 Determination of centrality definition 24
• Chapter 3 Measurements of Ξ(1530)0 in p–Pb and Pb–Pb collisions 27
• 3.1 Ξ(1530)0-reconstruction 27
• 3.1.1 Data sample and event selection 28
• 3.1.2 Track and topological selection criteria 33
• 3.1.3 Particle identification 35
• 3.1.4 Signal extraction 40
• 3.2 Efficiency correction 63
• 3.3 Corrected pT-spectra 67
• 3.4 Systematic uncertainties 69
• Chapter 4 Resultsanddiscussion 74
• 4.1 Ξ(1530)0 transverse momentum spectra 74
• 4.2 Particle yield ratios 77
• 4.2.1 Integrated particle ratio to ground state particle 77
• 4.2.2 Integrated particle ratio to π 83
• 4.3 Multiplicity and mass dependence of ⟨pT⟩ 86
• 4.4 Conclusions and outlook 88