Hough Transform Tracking and Data Analysis in Minimax

Senior Thesis submitted to the Case Western Reserve University Physics Department, May 1995. Note: the following files (the chapter headers are links to files) are all in postscript format. Please send comments to kangas@mit.edu

Thesis Overview

This thesis represents two and a half years of work as a collaborator on MiniMax -- Fermilab Experiment T-864 which seeks to discern chiral condensate signatures in the far-forward direction and perform other studies such as charm production. Hough Transform Tracking refers to one of the methods of charged particle track reconstruction used by the collaboration, the method which I worked to develop. This thesis details the algorithms and theory behind the Hough Transform method as well as analyses it's strengths and weaknesses and applicability to various forms of data analysis. Several ways of analyzing the resultant data from any of the collaborations trackers are also examined and suggestions made. Also included are detailed tables of the positions and alignments of many of the detector components. As of the writing of this document, the experiment was still very much into the data taking stage and had not performed much detailed analysis.

Contents

PRELIMINARIES

Title Page, Acknowledgments, Table of Contents, List of Illustrations, List of Abbreviations. (19k bytes long).

CHAPTER 1. OVERVIEW OF EXPERIMENT T-864

1.1 Objectives

1.2 Description of the Apparatus

1.3 Preview of Data Analysis (52k)

CHAPTER 2. INTRODUCTION TO TRACKING

2.1 Single-Vertex Hough Transform

2.2 Arbitrary-Vertex Hough Transform (129k)

CHAPTER 3. IMPLEMENTATION OF THE ARBITRARY VERTEX HOUGH TRANSFORM ALGORITHM

3.1 General Comments

3.2 The Minimum Planes Cut

3.3 The Least-Squares Fit

3.4 Probability Distributions

3.5 Identifying Equivalent Tracks

3.6 Track Quality Distributions

3.7 Interfacing the Computer Code

3.8 Data Summary Files (220k)

CHAPTER 4: DATA ANALYSIS

4.1 Track Origin Distributions

4.2 Matching Heads and Tails

4.3 Two-Track Vertices

4.4 Identifying Charged and Neutral Particles

4.5 Evaluation of Efficiencies and Systematic Errors (132k)

APPENDIX A. DETECTOR COMPONENTS

A.1 The Multiple Wire Proportional Chambers

A.2 The Beam Pipe

A.3 The Scintillator and Electromagnetic Calorimeter (82k)

APPENDIX B. SOURCE CODE FOR AVHT IMPLEMENTATION

Source code for the AVHT Tracker and Data Analysis addons. (89k)

APPENDIX C. EXAMPLE OFFLINE INTERFACE

Source code and Makefile. (8k)

APPENDIX D. EXAMPLE DST ANALYSIS PROGRAM

Source code and makefile. (9k)