利用CMS探測器量測7TeV下的Zγ產生截面

以作者查詢圖書館館藏

、以作者查詢臺灣博碩士

、以作者查詢全國書目

、勘誤回報

、線上人數：32

、訪客IP：18.224.32.86

姓名

劉宗凱(Zong-Kai Liu) 查詢紙本館藏

畢業系所

物理學系

論文名稱

利用CMS探測器量測7TeV下的Zγ產生截面
(Measurement of Zγ production in pp collision at √s = 7 TeV with the CMS detector at the LHC)

相關論文

★ 宇宙射線中的質子能譜	★ 建構空氣簇射探測器及測量海平面宇宙射線通量
★ 宇宙射線中正電子和電子的能譜	★ 建構粒子能譜探測器及量測海平面上質子能譜分布
★ 在康卜吞成像光譜儀內的gamma射線事件的分析	★ Study of Zγ-> e+e-γ Process with CMS Detector at Large Hadron Collider
★ 康卜吞成像光譜儀數據讀出系統	★ 質子照影成像使用GEANT4蒙特卡羅模擬研究
★ 以CMS 偵測器在質心質量為8TeV使用雙渺子和三秒子頻道尋找雙電荷希格斯玻色子	★ 在質子對撞能量8TeV下尋找具有雙電子雙渺子末態的激發態輕子
★ Measurement of Zγ production in 5 fb-1 of pp collisions at √s = 7 TeV with the CMS detector	★ Search for a Higgs boson decaying into γ∗γ → eeγ in pp collisions at √s = 8 TeV with the CMS detector
★ Measurement of Z boson production in the electron decay channel in p+Pb collisions at √sNN = 5.02 TeV with the CMS detector	★ 火花偵測器的製成
★ LHC phenomenology and renormalization of Georgi-Machacek model	★ Search for the production of two Higgs bosons in the final state with two photons and two b quarks in proton-proton collision at √s = 13 TeV

檔案

[Endnote RIS 格式]

[Bibtex 格式]

[相關文章]

[文章引用]

[完整記錄]

[館藏目錄]

[檢視]

[下載]

本電子論文使用權限為同意立即開放。
已達開放權限電子全文僅授權使用者為學術研究之目的，進行個人非營利性質之檢索、閱讀、列印。
請遵守中華民國著作權法之相關規定，切勿任意重製、散佈、改作、轉貼、播送，以免觸法。

摘要(中)

Zγ生產的量測能提供測試電弱理論結構的機會，也能給予新物理是否存在的線索。此篇論文利用CMS蒐集的 36 pb-1 的質子質子對撞數據，呈現了第一次在總碰撞能量7 TeV下的Zγ產生截面的量測，並選擇Z衰變為電子當作訊號事件。此產生截面量測是針對光子橫向能量大於10GeV，光子與電子空間上的分離ΔR(l, γ) 大於0.7，且輕子對恆定質量大於50GeV。量測的Zγ產生截面為9.5 ± 1.4（統計誤差）± 0.7（統計誤差）± 0.4（光度誤差）pb，與標準模型預測的Zγ產生截面9.6 ± 0.4 pb相符合。

摘要(英)

The measurement of Zγ production can provide an opportunity for examining the gauge sector of the Standard Model, and evidences for the existence of new physics. This thesis presents the first cross-section measurement of Zγ → e+e-γ at √s = 7 TeV using 36 pb-1 of proton-proton collision data collected by CMS. The cross-section is measured for the photon transverse energy ETγ > 10 GeV, spatial separation from charged leptons ΔR(l, γ) > 0.7 and dilepton invariant mass Mll > 50 GeV. The σ(pp → Zγ + X) × B(Z → e+e-) is measured to be 9.5 ± 1.4 (stat.) ± 0.7 (syst.) ± 0.4 (lumi.) pb, in agreement with Standard Model prediction of 9.6 ± 0.4 pb.

關鍵字(中)

★ 高能實驗

關鍵字(英)

★ CMS
★ di-boson

論文目次

摘要………………………………………………………………………i
Abstract…………………………………………………………ii
誌謝………………………………………………………………………iii
Contents…………………………………………………………iv
List of Figure…………………………………………vi
List of Table……………………………………………viii
Chapter 1 Introduction………………………………………………………1
Chapter 2 The CMS Experiment at LHC……………………4
2.1 The Large Hardon Collider…………………………………4
2.2 The Compact Muon Solenoid…………………………………5
2.2.1 Magnet……………………………………………………………………………6
2.2.2 Inner Tracker System………………………………………7
2.2.3 Electromagnetic Calorimeter……………………8
2.2.4 Hadronic Calorimeter……………………………………10
2.2.5 Muon System……………………………………………………………11
2.3 Trigger and Data Acquisition………………………12
2.3.1 Level-1 Trigger…………………………………………………13
2.3.2 High Level Triggers………………………………………13
2.4 Electron and Photon Reconstruction………14
2.4.1 Supercluster Reconstruction…………………14
2.4.2 Photon Reconstruction…………………………………15
2.4.3 Electron Reconstruction……………………………16
2.5 Luminosity measurement at CMS……………………17
Chapter 3 Overview of Zγ Production…………………21
3.1 Standard Model……………………………………………………………21
3.2 EWK Theory………………………………………………………………………22
3.3 Zγ Production and anomalous Triple Gauge Coupling…24
3.4 Review of Zγ Measurement…………………………………26
Chapter 4 Analysis Method……………………………………………28
4.1 Data and Monte Carlo samples………………………28
4.2 Anomalous signals in the ECAL……………………30
4.3 Object Identification…………………………………………33
4.3.1 Trigger………………………………………………………………………39
4.3.2 Electron Selection…………………………………………39
4.3.3 Photon Selection………………………………………………40
4.4 Measurement of efficiencies…………………………40
4.4.1 Tag and Probe Method……………………………………40
4.4.2 Electron reconstruction efficiency………………………42
4.4.3 Electron selection efficiency……………43
4.4.4 Trigger efficiency…………………………………………44
4.4.5 Photon reconstruction efficiency……45
4.4.6 Photon selection efficiency…………………46
4.4.7 Correction factor……………………………………………47
4.5 Background estimation…………………………………………49
4.5.1 Ratio Method…………………………………………………………49
4.5.2 Template Method…………………………………………………54
Chapter 5 Measurement of Zγ cross-section…60
5.1 Event selection…………………………………………………………60
5.2 Background estimation…………………………………………64
5.3 Cross-section measurement………………………………66
5.4 Systematic uncertainty………………………………………67
5.4.1 Systematic uncertainty on A×εMC………67
5.4.2 Systematic uncertainty on ρeff…………68
5.4.3 Systematic uncertainty on background estimation………68
5.4.4 Systematic uncertainty on Luminosity…………71
5.4.5 Summary of Systematic uncertainty…………………72
5.5 Result and comparison with theoretical prediction………72
5.5.1 Theoretical Prediction………………………………72
5.5.2 Results………………………………………………………………………73
Chapter 6 Conclusion…………………………………………………………76
Bibliography………………………………………………………………………………78
Appendix A Limits on Anomalous Trilinear Gauge Boson Couplings…82
Appendix B The Nuclear Compton Telescope (NCT) Project…………85

參考文獻

[1] The LEP Higgs working group, Phys. Lett. B 565 61 (2003)
[2] CDF and D0 Collaborations, "Combination of Tevatron Searches for the Standard Model Higgs Boson in the W+W- Decay Mode", Phys. Rev. Lett. 104, (2010)
[3] P. Fayet, "Mixing Between Gravitational and Weak Interactions Through the Massive Gravitino", Phys. Lett. B70 (1977)
[4] H. Baer, M. Brhlik, C. H. Chen et al., "Signals for the Minimal Gauge-Mediated Supersymmetry Breaking Model at the Fermilab Tevatron Collider", Phys. Rev. D55 (1997)
[5] H. Baer, P. G. Mercadante, X. Tata et al., "Reach of Tevatron Upgrades in Gauge-Mediated Supersymmetry Breaking Models", Phys. Rev. D60 (1999)
[6] S. Dimopoulos, S. Thomas, and J. D. Wells, "Sparticle Spectroscopy and Electroweak Symmetry Breaking with Gauge-Mediated Supersymmetry Breaking", Nucl. Phys. B488 (1997)
[7] J. R. Ellis, J. L. Lopez, and D. V. Nanopoulos, "Analysis of LEP Constraints on Supersymmetric Models with a Light Gravitino", Phys. Lett. B394 (1997)
[8] M. Dine, A. Nelson, Y. Nir et al., "New Tools for Low Energy Dynamical Supersymmetry Breaking", Phys. Rev. D53 (1996)
[9] G. F. Giudice and R. Rattazzi, "Gauge-Mediated Supersymmetry Breaking", in Perspectives on Supersymmetry, World Scientific, Singapore, (1998)
[10] P. Meade, N. Seiberg, and D. Shih, "General Gauge Mediation", Prog. Theor. Phys. Suppl. 177 (2009)
[11] M. Buican, et al., "Exploring General Gauge Mediation", JHEP 0903 (2009)
[12] The CMS Collaboration, "Search for Supersymmetry in pp Collisions at 7 TeV in Events with Jets and Missing Transverse Energy", CERN-PH-EP/2010-084 (2011)
[13] The ATLAS Collaboration, "Search for supersymmetry in pp collisions at √s = 7 TeV in final states with missing transverse momentum and b-jets", CERN-PH-EP/2011-038 (2011)
[14] The ATLAS Collaboration, "Search for high-mass states with one lepton plus missing transverse momentum in proton-proton collisions at √s = 7 TeV with the ATLAS detector", CERN-PH-EP-2011-023 (2011)
[15] The CMS Collaboration, "Search for a W' boson decaying to a muon and a neutrino in pp collisions at √s = 7 TeV", CERN-PH-EP/2011-012 (2011)
[16] The ATLAS Collaboration, "Search for high mass di-lepton resonances in pp collisions at √s = 7 TeV with the ATLAS experiment", CERN-PH-EP-2011-037 (2011)
[17] The CMS Collaboration, "Search for Resonances in the Dilepton Mass Distribution in pp Collisions at √s = 7 TeV", CERN-PH-EP/2011-002 (2011)
[18] N. Arkani-Hamed, S. Dimopoulos, and G. Dvali, "The Hierarchy Problem and New Dimensions at a Millimeter", Phys.Lett.B 429 (1998)
[19] V. Buscher, K. Jakobs, Int. J. Mod. Phys. A 20 (2005)
[20] A. Djouadi, J. Kalinowski, M. Spira, Comput. Phys. Commun. 108 (1998)
[21] G.A. Kozlov, Phys. Rev. D 72 (2005)
[22] S. Ono, Acta Phys. Pol. B 15 (1984)
[23] O. Cakir, R. Ciftci, E. Recepoglu, S. Sultansoy, Acta Phys. Pol. B 35 (2004)
[24] C.T. Hill, E.H. Simmons, Phys. Rep. 381 (2003)
[25] C.T. Hill, E.H. Simmons, Phys. Rep. 390 (2004)
[26] J.P. Skittrall, arXiv: 0809.4383 [hep-ph].
[27] L. Evans, (ed. ) and P. Bryant, (ed. ), "LHC Machine", JINST 3 (2008)
[28] https://twiki.cern.ch/twiki/bin/view/CMSPublic/LumiPublicResults2010
[29] CMS Collaboration, CMS Physics TDR Vol. 1, CERN/LHCC/2006-001 (2006)
[30] CMS Collaboration, "The CMS experiment at the CERN LHC", JINST 3 (2008)
[31] CMS Collaboration, "Studies of Tracker Material". CMS-PAS-TRK-10-003 (2010).
[32] CMS Collaboration, "Tracking and Vertexing Results from First Collisions". CMS-PAS-TRK-10-001 (2010).
[33] CMS Collaboration, " Measurement of the InclusiveW and Z Cross Section in pp Collisions at √s = 7 TeV: Update with full 2010 statistics". CMS-AN 10-395 (2010).
[34] CMS Collaboration, "Time Reconstruction and Performance of the CMS Electromagnetic Calorimeter", J. Instrum. 5 (2009)
[35] CMS Collaboration, " Jet Energy Resolution in CMS at √s = 7 TeV". CMS-PAS-JME-10-014 (2010).
[36] CMS Collaboration, "Performance of CMS Muon Reconstruction in Cosmic-Ray Events", J. Instrum. 5 (2009)
[37] CMS Collaboration, CMS TDR 6.1, CERN/LHCC 2000-38 (2000)
[38] CMS Collaboration, CMS TDR 6.2, CERN/LHCC 2002-26 (2002)
[39] M. Anderson et al., "Review of clustering algorithms and energy corrections in ECAL", CMS IN-2010/008 (2010).
[40] CMS Collaboration, "Photon reconstruction and identification at √s = 7 TeV". CMS-PAS-EGM-10-005 (2010).
[41] M. Pioppi, "Electron Pre-identification in the Particle Flow framework", CMS AN-2008-032 (2008).
[42] W. Adam et al., "Reconstructions of Electrons with the Gaussian-Sum Filter in the CMS Tracker at the LHC", J. Phys. G: Nucl. Part. Phys. 31 (2005).
[43] W. Adam, "Electron Reconstruction in CMS", CMS AN-2009-164 (2009).
[44] CMS Collaboration, "Electron commissioning results at √s = 7 TeV", CMS DP-2011-003 (2011).
[45] S. Van der Meer, "Calibration of the Active Beam Height in the ISR," internal CERN report, ISR-PO/68-31 (1968).
[46] CMS Collaboration, "Measurement of CMS Luminosity", CMS PAS EWK-10-004 (2010)
[47] CMS Collaboration, "Absolute luminosity normalization", CMS DPS-2011/002 (2011).
[48] S. M. White, Ph.D. thesis, "Determination of the Absolute Luminosity at the LHC", CERN-THESIS-2010-139.
[49] V. Balagura, "Notes on Van der Meer Scan for Absolute Luminosity Measurement", CERN Preprint
[50] P. A. Tilper and R. A. Llewellyn, "Modern Physics"(2000)
[51] P. W. Higgs. "Broken Symmetries, Massless Particles and Gauge Fields", Phys. Lett., 12 (1964)
[52] P. W. Higgs. "Spontaneous Symmetry Breakdown without Massless Bosons", Phys. Rev., 145 (1966)
[53] P. W. Higgs. "Broken Symmetries and the MAsses of Gauge Bosons", Phys.Lett., 13 (1964)
[54] S. L. Glashow, Nucl. Phys., 22, 579 (1961)
[55] S. Weinberg, Phys. Rev, Lett., 19, 1264 (1967)
[56] A. Salam, Proceedings of the Eight Nobel Symposium, ed. by N. Svartholm, Alqvist & Wiskell, Stockholm, (1968)
[57] U. Baur and E. Berger, "Probing the weak-boson sector in Zγ production at hadron colliders", Phys. Rev. D 47 (1993)
[58] U. Baur, S.Errede, J.Ohnemus,FSU-HEP-930322, UIUC-HEP-93-01, DTP/93/14 (1993)
[59] CDF Collaboration, ─Measurement of Zγ production in ppbar collisions at
√s = 1.96 TeV∥, Phys. Rev. D82 (2010)
[60] D0 Collaboration, "Zγ production and limits on anomalous ZZγ and Zγγ couplings in ppbar collisions at √s = 1.96 TeV", Phys. Lett. B 653 (2007)
[61] http://mcfm.fnal.gov/
[62] CDF Collaboration, "Limits on Anomalous Trilinear Gauge Couplings in Zγ Events from pp Collisions at √s = 1.96 TeV", http://arxiv.org/abs/1103.2990
[63] D0 Collaboration, "Measurement of the Zγ→ννγ cross section and limits on anomalous ZZγ and Zγγ couplings in ppbar collisions at √s = 1.96 TeV", Phys. Rev. Lett. 102 (2009)
[64] LEP EWWG, "A Combination of Preliminary Results on Gauge Boson Couplings Measured by the LEP Experiments", LEPEWWG/TGC/2003-01 (2004) (see http://lepewwg.web.cern.ch/LEPEWWG/lepww/tgc/)
[65] http://madgraph.hep.uiuc.edu/
[66] U. Baur, T. Han, and J. Ohnemus, "QCD corrections to hadronic Wg production with nonstandard WWg couplings", Phys. Rev. D 48 (1993) 5140–5161.
[67] CMS AN2010/357, "Characterization and treatment of anomalous signals in the CMS Electromagnetic Calorimeter"
[68] https://twiki.cern.ch/twiki/bin/view/CMSPublic/SWGuideEgammaIsolation
[69] D. Barge, et al., "Study of photon conversion rejection at CMS", CMS AN-2009/159 (2009)
[70] CMS AN2009/108, "Data driven selection cut tuning for electrons"
[71] https://twiki.cern.ch/twiki/bin/view/CMS/SimpleCutBasedEleID
[72] https://twiki.cern.ch/twiki/bin/view/CMS/PhotonID
[73] CMS AN2009/111, "Generic Tag and Probe Tool for Measuring Efficiency at CMS with Early Data"
[74] T. Bolton et. al., "Measurement of inclusive Wγ and Zγ cross sections and limits on anomalous trilinear gauge boson couplings at 7 TeV.", CMS AN 2010/279 (2011)
[75] J. Alcaraz Maestre et. al.,"Updated Measurements of the Inclusive W and Z Cross Sections at 7 TeV", CMS AN 2010/264 (2010)
[76] http://projects.hepforge.org/lhapdf/
[77] P. M. Nadolsky and Z. Sullivan, "PDF uncertainties in WH production at Tevatron", arXiv:hep-ph/0110378v2.
[78] CMS Collaboration, "Measurement of Wγ and Zγ production in pp collisions at √s = 7 TeV", http://arxiv.org/abs/1105.2758 (2011)
[79] L. Lyons, D. Gibaut, and P. Clifford, "How to combine correlated estimates of a single physical quantity", Nucl.Instrum.Meth. A270 (1988) 110.
[80] https://twiki.cern.ch/twiki/bin/view/CMSPublic/PhysicsResultsEWK

指導教授

郭家銘、張元翰
(Chia-Ming Kuo、Yuan-Hann Chang)

審核日期

2011-7-13

推文