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完整後設資料紀錄
DC 欄位 | 值 | 語言 |
---|---|---|
dc.contributor.advisor | 王名儒 | zh_TW |
dc.contributor.advisor | Min-Zu Wang | en |
dc.contributor.author | 張傳彧 | zh_TW |
dc.contributor.author | Chuan-Yu Chang | en |
dc.date.accessioned | 2023-03-19T23:29:45Z | - |
dc.date.available | 2023-11-10 | - |
dc.date.copyright | 2022-09-26 | - |
dc.date.issued | 2022 | - |
dc.date.submitted | 2002-01-01 | - |
dc.identifier.citation | [1] The Belle detector,Nuclear Instrumentsand Methods in Physics Research SectionA: Accelerators, Spectrometers, Detectors and Associated Equipment 479, 117 (2002), Detectors for Asymmetric B-factories. [2] H.-Y. Cheng and K.-C. Yang, Charmless exclusive baryonic B decays, Phys. Rev. D 66, 014020 (2002). [3] C.-K. Hou, W.-S. Chua, Three-body baryonic B → Λp ̄πdecays and such, The Eu- ropean Physical Journal C - Particles and Fields 29, 27 (2003). [4] M.-Z. Wang et al., Study of B+ → pΛγ, pΛπ0 and B0 → pΛπ−, Phys. Rev. D 76, 052004 (2007). [5] C.-K. Chua, W.-S. Hou, and S.-Y. Tsai, Charmless three-body baryonic B decays, Phys. Rev. D 66, 054004 (2002). [6] D. J. Lange, The EvtGen particle decay simulation package, Nucl. Instrum. Meth. A 462, 152 (2001). [7] R. Brun, A. C. McPherson, P. Zanarini, M. Maire, and F. Bruyant, GEANT 3 : user’s guide Geant 3.10, Geant 3.11, 1987. [8] Y.-J. L. K-F. Chen, T.-L. Kuo, Λ Selection at Belle, Belle Note 684 (2004). [9] M. Feindt and U. Kerzel, The NeuroBayes neural network package, Nucl. Instrum. Meth. A 559, 190 (2006). [10] G. C. Fox and S. Wolfram, Observables for the Analysis of Event Shapes in e+ e- Annihilation and Other Processes, Phys. Rev. Lett. 41, 1581 (1978). [11] PDG Value of D− → KSπ−, https:// pdglive.lbl.gov/BranchingRatio.action?desig=2parCode=S031home=MXXX035. [12] PDG Value of B0 → D−π+, https:// pdglive.lbl.gov/BranchingRatio.action?desig=1parCode=S018home=BXXX020. [13] Number of B in HadronB(J), https://belle.kek.jp/secured/nbb/nbb.html. [14] B. Bhuyan, High PT Tracking Efficiency Using Partially Reconstructed D∗ Decays, Belle Note 1165 (2010). [15] S.Nishida, Study of Kaon and Pion Identification Using Inclusive D∗ Sample, Belle Note 779 (2005). [16] M.-Z. W. Kai-Jen Tien, Proton identification efficiency study, Belle Note 1279 (2012). [17] PDG Value of Λ → pπ−, https:// pdglive.lbl.gov/ BranchingRatio.action?desig=1parCode=S018home=BXXX020. | - |
dc.identifier.uri | http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/85940 | - |
dc.description.abstract | 本次研究我們使用了日本 B 介子工廠的 7.72 億對 B 介子對來尋找及量測中性 B0 介子衰變至 pΣ ̄0π− 與 pΛ ̄π− 之衰變分之比用以確認其衰變分支比的理論預測及 pΛ ̄ 不變質量與重子對靜止座標系中質子與強子的角度分佈。在本次分析研究中, 我們在特定 pΛ ̄ 不變質量的區間中量測到 3.5σ 的中性 B0 介子衰變至 pΣ ̄0π− 的衰變分支比 0.86+0.28−0.26 ±0.07×10−6 及在 90% 的信心水準下衰變分支比上限 1.2×10−6, 並且更新了中性 B0 介子至 pΛ ̄0π− 衰變頻道的衰變分支比及在 pΛ ̄ 不 變質量與重子對靜止座標系中質子與強子的角度兩個維度的微分分支比。 | zh_TW |
dc.description.abstract | We use the data sample corresponding to an integrated luminosity of 711 f b−1 and contain 772 × 106 BB ̄ pairs collected around Υ(4S) with Belle detector at the super KEKB asymmetric-energy e+ e− collider to search for B0 → pΣ ̄0 π− and measure B0 → pΛ ̄ π− for the confirming of theoretic prediction of branching fraction and study of the threshold enhancement, polarized angle distribution. We measured the signal branching fraction of 0.86+0.28−0.26±0.07×10−6 with 3.5σ in threshold enhancement region(MpΛ<2.8GeV/c2), and the hint of threshold enhancement in B0 → pΣ ̄0π− channel. Also, we update the branching fraction of 3.15+0.25−0.24 ±0.16×10−6, and the differential branching fraction of MpΛ and cosθp dimensions respectively in B0 → pΛ ̄ π− channel. | en |
dc.description.provenance | Made available in DSpace on 2023-03-19T23:29:45Z (GMT). No. of bitstreams: 1 U0001-0609202218145500.pdf: 12394938 bytes, checksum: 4e67e0370aaaded5ab39c08a265cd723 (MD5) Previous issue date: 2022 | en |
dc.description.tableofcontents | Verification Letter from the Oral Examination Committee i Acknowledgements iii Abstract v 摘要 vii Contents ix List of Figures xiii List of Tables xix 1 Introduction 1 1.1 BelleExperiment.............................. 1 1.1.1 KEKBAccelerator.......................... 1 1.1.2 BelleDetector ............................ 2 1.1.2.1 BeamPipe........................ 3 1.1.2.2 Extreme Forward Calorimeter (EFC) ..........4 1.1.2.3 Silicon Vertex Detector (SVD) .............5 1.1.2.4 CentralDriftChamber(CDC) ..............6 1.1.2.5 Aerogel Cherenkov Counter System (ACC) ...... 8 1.1.2.6 TimeofFlight(TOF) .................. 10 1.1.2.7 Electromagnetic Calorimeter (ECL) . . . . . . . . . . 11 1.1.2.8 KL and μ DetectionSystem(KLM) . . . . . . . . . . . 12 1.2 Motivation ................................. 13 1.2.1 b→sTransitionDecay ....................... 13 1.2.2 ThresholdEnhancementStudy ................... 13 1.2.3 cosθpAsymmetry .......................... 14 2 Event Reconstruction and Selection 17 2.1 DataSample ................................ 17 2.1.1 BelleDataSample.......................... 17 2.1.2 SignalMonteCarlo ......................... 17 2.1.3 BackgroundMonteCarlo ...................... 19 2.2 Reconstruction of Candidate........................ 20 2.3 EventSelection............................... 20 2.3.1 p± and π± Selection......................... 20 2.3.2 Λ Selection.............................. 21 2.4 KinematicVariables ............................ 23 2.5 SelectionSummary............................. 24 3 Background Study 25 3.1 Overview of Background Study ...................... 25 3.2 Continuum Suppression .......................... 26 3.2.1 Sideband Data and Monte Carlo Comparison . . . . . . . . . . . 26 3.2.2 ∆Z .................................. 27 3.2.3 cosθB................................. 28 3.2.4 Thrust angle ............................. 28 3.2.5 Sphericity .............................. 29 3.2.6 q·r.................................. 30 3.2.7 Fox-Wolframmoments ....................... 31 3.2.8 Kakuno SuperFox-Wolfram(KSFW)................ 31 3.2.9 Other training variables ....................... 33 3.3 BestFOM.................................. 34 3.4 PeakingBackgroundVeto ......................... 35 3.4.1 GenericBB ̄.............................. 35 3.4.2 Rare B Decay ............................ 37 3.5 BestCandidateSelection.......................... 38 3.6 Conclusion of Background Study ..................... 39 3.7 Table of selection counting......................... 40 4 Yield Extraction 43 4.1 Introduction................................. 43 4.2 CorrelationCheck ............................. 43 4.3 PDFModeling ............................... 45 4.4 FitterTest.................................. 48 4.4.1 ToyMCensembletest ........................ 48 4.4.2 Gsimensembletest ......................... 50 4.5 MpΛ ̄Distribution Study with MC Sample ................. 52 5 Control Sample 57 5.1 DataSample ................................ 57 5.2 EventSelection............................... 58 5.3 BackgroundSuppression.......................... 58 5.4 PDFModeling ............................... 58 5.5 FittingResult................................ 60 5.6 Calibration on Continuum Suppression Efficiency . . . . . . . . . . . . 61 5.7 Conclusion ................................. 61 6 Unblind Results 63 6.1 FittingResults ............................... 63 6.2 ThresholdEnhancementResult ...................... 66 6.3 cosθpAsymmetry ............................. 70 6.4 PDFUncertainty .............................. 71 6.5 SignificanceEstimation .......................... 71 6.6 Summary.................................. 72 7 Systematic Uncertainty 73 7.1 Number of BB ̄pairs uncertainty ...................... 73 7.2 TrackingUncertainty............................ 73 7.3 ChargedParticleIdentificationUncertainty . . . . . . . . . . . . . . . . 73 7.4 Λ Selection Uncertainty .......................... 74 7.5 SecondarySubdecayUncertainty ..................... 74 7.6 ContinuumSuppressionUncertainty.................... 74 7.7 MC Modeling................................ 75 7.8 PDF Uncertainty .............................. 75 7.9 Summary of Systematic Error ....................... 76 7.10 Summary of CalibrationFactor ...................... 76 8 Conclusion 77 8.1 UpperLimitEstimation .......................... 77 8.2 Summary.................................. 78 A Trianing Variable 79 B ToyMC Fitter Test 83 C Gsim Fitter Test 87 Bibliography 91 | - |
dc.language.iso | en | - |
dc.title | 在 Belle 實驗中尋找 B0 → pΣ ̄0π− 衰變與測量 B0 → pΛ ̄π− 之衰變率 | zh_TW |
dc.title | Searching for B0 → pΣ ̄0π− and Measurement of B0 → pΛ ̄ π − at Belle Experiment | en |
dc.type | Thesis | - |
dc.date.schoolyear | 110-2 | - |
dc.description.degree | 碩士 | - |
dc.contributor.oralexamcommittee | 張寶棣;徐靜戈;張敏娟 | zh_TW |
dc.contributor.oralexamcommittee | Pao-Ti Chang;Jing-Ge Hsu;Min-Chuan Chang | en |
dc.subject.keyword | Belle 實驗,B 介子,含重子衰變, | zh_TW |
dc.subject.keyword | Belle,B meson,Baryonic decay, | en |
dc.relation.page | 92 | - |
dc.identifier.doi | 10.6342/NTU202203205 | - |
dc.rights.note | 同意授權(全球公開) | - |
dc.date.accepted | 2022-09-23 | - |
dc.contributor.author-college | 理學院 | - |
dc.contributor.author-dept | 物理學系 | - |
dc.date.embargo-lift | 2025-12-31 | - |
顯示於系所單位: | 物理學系 |
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