The E and B EXperiment: A balloon-borne cosmic microwave background anisotropy probe Seth Hillbrand Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Graduate School of Arts and Sciences COLUMBIA UNIVERSITY 2014 c 2014 Seth Hillbrand All Rights Reserved ABSTRACT The E and B EXperiment: A balloon-borne cosmic microwave background anisotropy probe Seth Hillbrand The E and B Experiment (EBEX), is a balloon-borne sub-orbital cosmic microwave background polarimeter, designed to measure polarization levels in the microwave spectrum. EBEX recently completed an 11-day Antarctic long duration balloon (LDB) science flight in January, 2013. 1000 transition edge sensor bolometric detectors in ∼ three frequency bands centered at 150, 250 and 410 GHz sampled a large segment of the southern sky. Over 1.5TB of data were collected during the LDB flight. In this thesis, we describe the design and performance of the EBEX software components monitoring and controlling the system during the flight, including automation, telemetry, data storage and readout array management. We also describe the design and development of a novel attitude reconstruction system for a balloon-borne pointed observation platform based on a daytime star camera and 3-axis gyroscopes. The data gathered during the LDB flight are analyzed and the results presented showing attitude reconstruction error at less than 2000 RMS for an 80 second interval. Table of Contents 1 Introduction1 2 EBEX Science4 2.1 Concordance Cosmology.........................4 2.1.1 Expanding Universe.......................6 2.1.2 Flat Universe...........................9 2.1.3 Hot, Dense Early Universe....................9 2.1.4 Dark Matter Universe...................... 10 2.1.5 Dark Energy Dominated Universe................ 12 2.1.6 Concordance Constraints..................... 12 2.2 Inflation.................................. 14 2.3 Cosmic Microwave Background Radiation............... 15 2.3.1 CMB Polarization......................... 17 2.4 EBEX B-Mode Science.......................... 19 2.4.1 Scan Strategy........................... 20 2.5 Summary................................. 23 3 The EBEX Instrument 24 3.1 Overview.................................. 24 3.2 Cryostat.................................. 25 3.2.1 Half-Wave Plate.......................... 26 i 3.2.2 Focal Planes............................ 27 3.2.3 Readout.............................. 28 3.3 Gondola.................................. 31 3.3.1 Attitude Control System..................... 33 3.3.2 Attitude Sensors......................... 33 3.4 Communications............................. 40 3.4.1 BLASTBus............................ 40 3.4.2 RS-232............................... 42 3.4.3 CANBus.............................. 42 3.4.4 TCP/IP Network......................... 44 3.5 Software.................................. 45 3.5.1 Threading............................. 47 3.5.2 Disk Management......................... 53 3.5.3 BLASTBus Interface....................... 61 3.5.4 Automation............................ 62 3.5.5 Telemetry............................. 66 3.6 Summary................................. 71 4 Attitude Reconstruction 72 4.1 Overview.................................. 72 4.2 Theory................................... 75 4.2.1 Wahba's Problem......................... 75 4.2.2 Quaternion Formalism...................... 76 4.2.3 Creating a Rotation Matrix................... 78 4.2.4 Quaternion Rotation....................... 80 4.2.5 Quaternion Kinematics...................... 80 4.2.6 Kalman Filtering......................... 82 4.2.7 Particle Filters.......................... 83 4.2.8 Sequential Importance Resampling............... 86 ii 4.3 EBEX Sensor Parameterization..................... 95 4.3.1 Gyroscope Readouts....................... 95 4.3.2 Star Camera Parameterization.................. 98 4.3.3 Field Matching.......................... 104 4.3.4 Filter Fitness Functions..................... 110 4.3.5 Time Dependence......................... 112 4.4 Verification Metrics............................ 114 4.4.1 Simulated Data.......................... 114 4.4.2 Results............................... 118 5 LDB Flight Attitude Reconstruction 125 5.1 Summary of the EBEX Long Duration Flight............. 125 5.2 Star Camera Solutions.......................... 129 5.2.1 Generalized Symmetric Weighting Analysis........... 130 5.2.2 Scan Length Distribution..................... 132 5.3 Gyroscope Readings........................... 133 5.3.1 Spike Identification........................ 134 5.3.2 Spike Verification......................... 139 5.3.3 Spike Removal........................... 140 5.4 Particle Filter Application........................ 143 5.4.1 Parameter Verification...................... 144 5.4.2 Attitude Reconstruction..................... 146 5.5 Summary................................. 149 Bibliography 150 A Algorithm Details 168 A.1 FIFO Algorithms............................. 168 A.2 Kernel Queuing.............................. 169 A.3 SIR Particle Filter............................ 171 iii A.3.1 Sequential Importance Resampling............... 171 A.4 Adaptive Boosting............................ 172 B Automation Files 173 iv List of Figures 1.1 Atmospheric transmission at microwave frequencies for balloon-borne and ground-based experiments......................2 2.1 Concordance Cosmology.........................5 2.2 Weyl's Postulate.............................7 2.3 Planck + BAO Constraints on ΩΛ-Ωm ................. 10 2.4 Planck Constraints on r - ns with Inflationary Models......... 15 2.5 CMB Temperature Power Spectrum Anisotropies........... 16 2.6 Polarization from Density Fluctuations and Thompson Scattering.. 17 2.7 Predicted Anisotropy Power Spectra for Best-Fit ΛCDM Values... 19 2.8 EE and BB Power Spectrum Measurements.............. 20 2.9 EBEX Expected Constraints on Power Spectra............. 21 2.10 EBEX Scan Strategy........................... 22 3.1 EBEX Internal Optics.......................... 25 3.2 HWP Schematic.............................. 26 3.3 EBEX Focal Plane............................ 27 3.4 SQUID Board............................... 29 3.5 The EBEX Cryostat with Associated Readout Electronics...... 30 3.6 EBEX Readout Schematic........................ 30 3.7 Gondola CAD Drawing.......................... 32 3.8 Fiber-Optic Gyro............................. 36 v 3.9 Allan Variance Measurement....................... 37 3.10 BLASTBus Word............................. 41 3.11 EBEX Ethernet network diagram.................... 44 3.12 Flight Control Program Block Diagram................. 46 3.13 Memory Layout of the FIFO Queue................... 48 3.14 Performance of the EBEX FIFO queue................. 52 3.15 EBEX Disk Pressure Vessels....................... 54 3.16 Typical EBEX File Lifecycle....................... 58 3.17 Performance of the AoE Disk Subsystem................ 60 3.18 Signal Handling in the EBEX Automator................ 65 3.19 EBEX Communication Paths...................... 67 3.20 Packetslinger Header Definition...................... 69 4.1 Rotation Schematic............................ 74 4.2 Sequential Importance Resampling................... 87 4.3 Particle Regularization.......................... 90 4.4 Image of the 3-Axis Gyroscope Box................... 96 4.5 Symmetric Weighting........................... 102 4.6 Star Pattern Matching.......................... 104 4.7 Star Field Hash Word.......................... 105 4.8 Camera Platescale Variation....................... 109 4.9 Simulated Scans.............................. 115 4.10 Roll Uncertainty between Two Stars.................. 117 4.11 Gyro Parameter Optimization...................... 118 4.12 Rotation Parameter Convergence.................... 120 4.13 Misalignment Parameter Convergence.................. 121 4.14 Bias Parameter Tracking......................... 121 4.15 Reconstruction Histograms........................ 122 4.16 Power Spectrum Contamination..................... 124 vi 5.1 EBEX Flight Trajectory......................... 126 5.2 EBEX Flight Altitude.......................... 127 5.3 EBEX LDB Azimuth........................... 128 5.4 Star Camera Image Noise Reduction.................. 130 5.5 Comparison of Centroiding Errors between Weighted and Unweighted Star Camera Images........................... 131 5.6 Star Camera Solution Time Distribution................ 132 5.7 Comparison of Paired Gyroscope Timestreams............. 133 5.8 Gyroscope Time Series Spikes...................... 135 5.9 Gyroscope Poincar´eMap Filter..................... 139 5.10 Example Spike Removal......................... 142 5.11 Distribution of Star Camera Rotation Offsets.............. 145 5.12 Star Camera-Gyroscope Uncertainty Pairing as a Function of Scan Length148 5.13 Combined Gyroscope Uncertainties as a Function of Scan Length.. 149 B.1 The Document Type Definition file that details the full structure of EBEX automation files. After creation or modification, the automation XML file is verified for grammar against this definition file....... 174 B.2 The cryogenic cooler cycle initiation procedure and subprocedure as used in the EBEX LDB flight...................... 175 B.3 Cryogenic Cooler Cycle Step 1...................... 176 vii List of Tables 2.1 ΛCDM Constraints from Planck and WMAP............. 13 3.1 EBEX Attitude Sensors and Their Associated Uncertainties..... 34 3.2 EBEX Telemetry Links and Associated Characteristics........ 68 4.1 Particle Filter Parameter