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Measurement of the Cross Section for Elastic Scattering of Electron Neutrinos on Electrons

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Measurement of the Cross Section for Elastic Scattering of Electron Neutrinos on Electrons Louisiana State University LSU Digital Commons LSU Historical Dissertations and Theses Graduate School 1998 Measurement of the Cross Section for Elastic Scattering of Electron Neutrinos on Electrons. Neville Dinyar Wadia Louisiana State University and Agricultural & Mechanical College Follow this and additional works at: https://digitalcommons.lsu.edu/gradschool_disstheses Recommended Citation Wadia, Neville Dinyar, "Measurement of the Cross Section for Elastic Scattering of Electron Neutrinos on Electrons." (1998). LSU Historical Dissertations and Theses. 6874. https://digitalcommons.lsu.edu/gradschool_disstheses/6874 This Dissertation is brought to you for free and open access by the Graduate School at LSU Digital Commons. It has been accepted for inclusion in LSU Historical Dissertations and Theses by an authorized administrator of LSU Digital Commons. For more information, please contact [email protected]. INFORMATION TO USERS This manuscript has been reproduced from the microfilm master. UMI films the text directly from the original or copy submitted. Thus, some thesis and dissertation copies are in typewriter lace, while others may be from any type of computer printer. The quality of this reproduction is dependent upon the quality of the copy submitted. Broken or indistinct print, colored or poor quality illustrations and photographs, print bleedthrough, substandard margins, and improper alignment can adversely affect reproduction. In the unlikely event that the author did not send UMI a complete manuscript and there are missing pages, these will be noted. Also, if unauthorized copyright material had to be removed, a note will indicate the deletion. Oversize materials (e.g., maps, drawings, charts) are reproduced by sectioning the original, beginning at the upper left-hand comer and continuing from left to right in equal sections with small overlaps. Each original is also photographed in one exposure and is included in reduced form at the back of the book. Photographs included in the original manuscript have been reproduced xerographically in this copy. Higher quality 6” x 9” black and white photographic prints are available for any photographs or illustrations appearing in this copy for an additional charge. Contact UMI directly to order. UMI A Bell & Howell Information Company 300 North Zeeb Road, Ann Arbor MI 48106-1346 USA 313/761-4700 800/521-0600 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. MEASUREMENT OF THE CROSS SECTION FOR ELASTIC SCATTERING OF ELECTRON NEUTRINOS ON ELECTRONS A Dissertation Submitted to the Graduate Faculty of the Louisiana State University and Agricultural and Mechanical College in partial fulfillment of the requirements for the degree of Doctor of Philosophy in The Department of Physics and Astronomy by Neville D. Wadia B.Sc.(Hons.). Indian Institute of Technology, 1991 M.S.. Louisiana State University. 1995 December. 1998 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. UMI Number: 9 9 2 2 1 2 3 UMI Microform 9922123 Copyright 1999, by UMI Company. All rights reserved. This microform edition is protected against unauthorized copying under Title 17, United States Code. UMI 300 North Zeeb Road Ann Arbor, MI 48103 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. To my parents, Zarine and Dinyar Wadia ii Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. ACKNOWLEDGEMENTS The past five years of my life as a graduate student have been stimulating, enjoyable and gratifying. I have been lucky to have been associated with LSU and the LSND experiment. Let me begin by conveying my deep appreciation and sincere gratitude to Professors Richard Imlay and Bill Metcalf for their guidance, knowledge and patience. They have been monumental in shaping my knowledge about experimental particle physics. I have greatly profited from their insight and experience. They have also painstakingly read my thesis time and time again and their suggestions and comments have been invaluable. I would also like to thank Hong Joo Kim for his guidance and friendship. I learnt about computing, physics analysis and a whole lot more from him. Regarding my stay at Los Alamos. I would like to thank Bill Louis and Hal White for their advice and guidance. I greatly appreciate their friendliness, their wit and how they would always find time for me and answer my queries. I thank Radomir and Guna for their friendship and will treasure our long conversations. I would like to thank Eric, Myung Kee and Adam for their friendship and advice. Rex and Ben have always taken care of my computing needs and I am grateful to them. I have learned a lot from Ion and Geoff and would like to thank them for the same. At LSLI, I would like to thank Professors Chan and McNeil for their guidance and advice. iii Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Finally, I would like to thank my family who have always supported me and encouraged my desire for knowledge, without whom none of this could have been possible. This work was supported by the United States Department of Energy under the grant DE-FG02-91ER40617. O ctober 15. 1998 Baton Rouge. Louisiana Los Alamos. New Mexico iv Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. TABLE OF CONTENTS ACKNOWLEDGMENTS ............................................................................. iii LIST OF TABLES ...............................................................................................vii LIST OF FIGURES ..........................................................................................viii ABSTRACT ......................................................................................................... xii CHAPTER 1 INTRODUCTION ....................................................................................... 1 1.1 Overview ........................................................................................... 1 1.2 The Electroweak Force .................................................................. 2 1.3 Electron Neutrino-EIectron Elastic Scattering ..................... 7 1.4 A Check of the Standard Model ............................................... 14 1.5 Previous Neutrino-EIectron Scattering Measurements . 17 2 THE LAMPF NEUTRINO BEAM ........................................................ L9 2.1 The Proton B e a m ......................................................................... 19 2.2 The Beam Stop .................................................................................20 2.3 The Neutrino B eam ..........................................................................23 2.4 The Beam Monte Carlo Simulation ...............................................26 3 THE LSND DETECTOR ............................................................................. 28 3.1 The Experimental S et-up ................................................................28 3.2 The D e te c to r ........................................................................................30 3.3 The Veto S h i e l d .................................................................................34 4 DATA AQUISITION AT LSND ............................................................41 4.1 E le c tro n ic s ........................................................................................... 41 4.2 Trigger .................................................................................................. 45 5 EVENT RECONSTRUCTION ................................................................... 53 5.1 D ata Readout .................................................................................... 53 5.2 Laser Calibration .................................................................................54 5.3 Event Reconstruction ...................................................................... 56 5.4 Energy Calibration ............................................................................. 65 5.5 Detector Sim ulation ..........................................................................69 6 EVENT SELECTION .................................................................................... 73 6.1 Electron Neutrino-EIectron Elastic Scattering ..........................73 6.2 Neutrino-EIectron Elastic Scattering for Muon-type Neu­ trinos ...............................................................................................73 6.3 Neutrino-Nucleus Interactions .................................................... 75 6.4 Cosmic-ray Background ...................................................................82 v Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 6.5 The Selection C riteria .......................................................................87 6.6 The Acceptance V alues ................................................................... 96 6.7 Summary ...............................................................................................97 7 REDUCTION OF COSMIC-RAY BACKGROUND ......................... 98 7.1 Motivation for Reduction of CR Background ......................... 98 7.2 Likelihood Analysis of Look-back Events ....................................99
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