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J/Psi $ Yield Modification in 200 Gev Per Nucleon Au+Au Florida State University Libraries 2016 J/# Yield Modification in 200 GeV Per Nucleon Au+Au Collisions with the PHENIX Experiment at RHIC Jeffrey Klatsky Follow this and additional works at the FSU Digital Library. For more information, please contact [email protected] FLORIDA STATE UNIVERSITY COLLEGE OF ARTS AND SCIENCES J/ψ YIELD MODIFICATION IN 200 GEV PER NUCLEON AU+AU COLLISIONS WITH THE PHENIX EXPERIMENT AT RHIC By JEFFREY CURRY KLATSKY A Dissertation submitted to the Department of Physics in partial fulfillment of the requirements for the degree of Doctor of Philosophy 2016 Copyright c 2016 Jeffrey Curry Klatsky. All Rights Reserved. Jeffrey Curry Klatsky defended this dissertation on April 7, 2016. The members of the supervisory committee were: Anthony Frawley Professor Co-Directing Dissertation Volker Crede Professor Co-Directing Dissertation Tim Cross University Representative Susan Blessing Committee Member Simon Capstick Committee Member The Graduate School has verified and approved the above-named committee members, and certifies that the dissertation has been approved in accordance with university requirements. ii To my parents, without whose constant love and support I would have quit long ago. iii ACKNOWLEDGMENTS I want to say something like, “Wow, I honestly don’t know how I made it this far.” But that would be a lie, because there is no doubt in my mind that I’ve only made it this far because of the countless people that have helped me in one way or another during my time as an FSU grad student. I have eight years worth of people to thank, so if a momentary lapse in my failing memory has caused me to forget you, I deeply apologize. I’ve got a lot to cover here, so bear with me. First and foremost, I thank my advisor, Tony. For showing me what it means to be a scientist, and how to pick apart a problem at the finest scale. For being willing to help me with even the most trivial of questions at a moment’s notice, even when they are about things I should know. For setting the bar high, so that I always tried to do better. And for sticking with me, even when things looked not so promising. To my committee, I realize that this may be the longest you’ve ever been on a Ph.D. student’s committee. Thank you for being patient with me as I wrapped things up and being understanding about last minute problems that seem to always find ways to emerge. To the FSU physics department, thank you for allowing me to stay as long as I did. Thank you for the opportunity to teach classes, which ended up being one of my favorite things about graduate school. To the PHENIX collaboration, especially those I sat shifts with, thank you for the good mem- ories, whether at BNL, workshops or at overseas conferences. Eastern Long Island is a pretty forgettable place, but those I’ve met have made the trips there unforgettable. Special thanks to Mihael and Ermias for their help with HBD-related issues. To the students who came to FSU physics department in the Fall of 2008, thanks for being a family during what was a difficult transition for everyone. That first semester was no doubt the hardest academic semester of my life, and I could not have made it through those courses without the help of everyone. I remember we would discuss things like, “Who is going to be the last one of us to graduate?”. Well guys, it’s me! To my fellow FSU nucs, including but not limited to Bemder, Smitch, Bookvalter, Dmac, Tony K, Pim, Turn-the-Tacos-into-Chili, Rutger and JP, thank you for making a building as ugly as iv NRB feel like home. Thanks for all the Momo’s Fridays, Panda Wednesdays, Dirac Lunch and the short-lived Voodoo Dog Thursdays and all our group lunches a thing. Thanks to Drs. Anthony Kuchera and Chris Levi Duston for Mega After Eight. We came, we saw, we rocked. MA84L. To my outside-the-field family, Az´ucar Dance Company, thank you for the amazing experiences and the chance to be involved in something I never thought I’d do. If someone had told me I’d end up performing and teaching salsa before I came to FSU, I’d have laughed in their face. Showing up to that first class in 2010 was one of the best decisions I’ve ever made. Special thanks to Dave, Daniel, Yingxue, Jeni, Mobes, Tayonce, VV and Deb for the incredible dances, support and friendship. To JB, Natty and Laura, thank you for always believing in me and supporting me, even after seeing me at my worst. To Arien, thank you for convincing me to stay in Tallahassee and not give up, even though I was at an all-time low my first semester. I know I would have left Florida if not for that phone call, so thank you for talking some sense into me. To Anthony, thanks for an awesome five and a half years. Our experiences with the struggles of grad school, exploring a new city and doing stuff like soccer, running and music together has really made me feel lucky to have had you as my friend. I really can’t imagine grad school being as memorable as it has been without you. To Dmac, thanks for not only being a friend, but also for your unending help with my work. I constantly badgered you while you worked 6 feet from me, and I badgered you when you moved 1600 miles away to Boulder, CO. You never ceased to lend a helping hand, and for that I am eternally grateful. Celeste, thank you for being so good to me as I got through the last leg of this thing. Your support means more to me than you know. Last but certainly not least, I thank my family: Mom, Dad, Gander, Maya and Bozo. Thank you for everything. v TABLE OF CONTENTS ListofTables.......................................... ... ix ListofFigures ......................................... ... x List of Abbreviations . xvi Abstract............................................. .xvii 1 Overview 1 2 Motivation 2 2.1 RelevantAspectsofQCD ................................ 2 2.1.1 Confinement .................................... 2 2.1.2 Quark Gluon Plasma . 4 2.2 Relativistic Heavy Ion Collisions . 5 2.2.1 Elliptic Flow and Quark Scaling . 5 2.2.2 Jet Suppression in Au+Au Collisions . 6 2.2.3 Small η/s andNear-PerfectFluidity . 7 2.2.4 ChemicalEquilibrium .............................. 9 2.2.5 Hard Probes . 9 2.3 Charmonium in Nuclear Collisions . 10 2.3.1 TimeScales..................................... 12 2.4 What Can We Learn from Charmonium? . 12 2.5 Motivation for this Analysis . 13 3 Charmonium in Nuclear Collisions 14 3.1 Observables....................................... 14 3.2 Brief Overview of J/ψ Measurements........................... 15 3.3 Cold Nuclear Matter Effects . 16 3.4 Hot Nuclear Matter Effects . 18 3.4.1 SPSResults..................................... 18 3.4.2 RHICResults.................................... 19 3.4.3 ALICE Results . 22 3.4.4 Comparison of Heavy Ion Data at Different Energies . 22 3.4.5 Models for Hot Nuclear Matter Effects . 24 3.5 Motivation for this Analysis . 26 4 Experiment 33 4.1 RHIC ............................................ 33 4.2 PHENIX........................................... 33 4.2.1 DriftChamber ................................... 35 4.2.2 Pad Chamber 1 . 36 4.2.3 Ring Imaging Cerenkov Detector . 38 vi 4.2.4 Electromagnetic Calorimeter . 39 4.2.5 Hadron Blind Detector . 41 4.2.6 Beam Beam Counter . 43 5 Analysis 44 5.1 CentralityDetermination ............................. 44 5.2 Detector QA and Run Group Assignments . 45 5.2.1 Drift Chamber and Pad Chamber 1 . 46 5.2.2 RICH, EMCal and HBD . 47 5.3 ElectronIdentification ............................... 49 5.3.1 HBD Min Pad Clusterizer . 49 5.3.2 Neural Network . 51 5.4 Signal Extraction . 52 5.4.1 Yield Extraction - Centrality Dependence . 54 5.4.2 Yield Extraction - pT Dependence ........................ 59 5.4.3 Radiative Tails . 60 5.5 Acceptance and Efficiency Corrections . 61 5.5.1 Simulation Chain . 62 5.5.2 Simulated J/ψ Line Shape . 63 5.5.3 Simulation to Data Matching . 64 5.5.4 Acceptance Calculation . 67 5.5.5 EmbeddingCorrection............................... 70 5.6 Invariant Yield and RAA .................................. 71 5.6.1 p + p Reference................................... 73 5.6.2 BinShiftCorrection ................................ 74 5.6.3 RAA ......................................... 78 5.6.4 Au+Au RAA vs Npart ............................... 79 5.6.5 RAA vs pT ...................................... 79 5.6.6 p2 vs N .................................... 80 h T i part 5.7 SystematicUncertainties. 81 5.7.1 BdN/dy vs Npart .................................. 82 5.7.2 RAA vs Npart .................................... 84 2 5.7.3 Bd N/dydpT vs pT ................................. 84 5.7.4 RAA vs pT ...................................... 85 5.7.5 p2 vs N .................................... 85 h T i part 6 Discussion and Comparison with Theory 88 6.1 RAA vs Npart ........................................ 88 2 6.2 B d N vs p ........................................ 91 dydpT T 6.3 RAA vs pT .......................................... 92 6.4 p2 vs N ........................................ 92 h T i part 7 Summary 98 vii Appendix A DC α vs φ Plots 100 B DC φ - Simulation/Data Comparison 104 C Acceptance Figures 107 Bibliography .......................................... 114 BiographicalSketch ..................................... 120 viii LIST OF TABLES 5.1 Npart and Ncoll values for their corresponding centrality classes. 45 5.2 Run groups and their respective number of runs and number of events. 48 5.3 Electron identification variables used in neural network. 53 5.4 Neural net cut values for each centrality bin. 53 5.5 Best fit parameters from Crystal Ball function. 57 5.6 Fit results and yields as a function of centrality.
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