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The Detection and Parameter Estimation of Binary Black Hole Mergers

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Syracuse University SURFACE Dissertations - ALL SURFACE August 2017 The detection and parameter estimation of binary black hole mergers Christopher Michael Biwer Syracuse University Follow this and additional works at: https://surface.syr.edu/etd Part of the Physical Sciences and Mathematics Commons Recommended Citation Biwer, Christopher Michael, "The detection and parameter estimation of binary black hole mergers" (2017). Dissertations - ALL. 791. https://surface.syr.edu/etd/791 This Dissertation is brought to you for free and open access by the SURFACE at SURFACE. It has been accepted for inclusion in Dissertations - ALL by an authorized administrator of SURFACE. For more information, please contact [email protected]. ABSTRACT In this dissertation we study gravitational-wave data analysis techniques for binary neutron star and black hole mergers. During its first observing run, the Advanced Laser Interferometer Gravitational-wave Observatory (Advanced LIGO) reported the first, direct observations of gravitational waves from two binary black hole mergers. We present the results from the search for binary black hole mergers which unambigu- ously detected the binary black hole mergers. We determine the effect of calibration errors on the detection statistic of the search. Since the search is not designed to pre- cisely measure the astrophysical parameters of the binary neutron star and black hole mergers, we use Bayesian methods to develop a new parameter estimation analysis. We demonstrate the performance of the analysis on the binary black hole mergers detected during Advanced LIGO's first observing run. We use the parameter estima- tion analysis to assess the ability of gravitational-wave observatories to observe a gap in the black hole mass distribution between 52 M and 133 M due to pair-instability supernovae. Finally, we use simulated signals added to the Advanced LIGO detec- tors to validate the search and parameter estimation analyses used to publish the detection of the astrophysical events. THE DETECTION AND PARAMETER ESTIMATION OF BINARY BLACK HOLE MERGERS By Christopher M. Biwer B.S. Applied Mathematics and Physics, University of Wisconsin-Milwaukee Dissertation Submitted in Partial Fulfillment of the Requirements for the degree of Doctor of Philosophy in Physics Syracuse University August 2017 Copyright c 2017 Christopher M. Biwer All rights reserved. Preface The work presented in this thesis stems from my participation in the LIGO Scientific Collaboration (LSC). This work does not reflect the scientific opinion of the LSC and it was not reviewed by the collaboration. Chapter2 is based on material from B .P. Abbott et al., \Binary Black Hole Mergers in the First Advanced LIGO Ob- serving Run," Phys. Rev. X 6, 041015 (2016) Chapter6 is based on material from C. Biwer et al., \Validating gravitational-wave detections: The Advanced LIGO hard- ware injection system," Phys. Rev. D 95, 062002 (2017) iv Acknowledgments First, I would like to express my gratitude and thanks to my advisor Duncan Brown. I have had the opportunity to work on a diverse set of projects and to learn from his broad knowledge of the detectors and gravitational-wave astronomy. He has been an excellent advisor and I am grateful for his mentorship. I have thoroughly enjoyed working with the Syracuse University Gravitational- wave Group. The breadth of expertise and the friendliness of this group has made it an exceptional environment to work. I would like to thank Peter Saulson who has always presented great pedagogy, and Stefan Ballmer for sharing his extensive knowledge of the detectors. I have frequently sought the help of Ryan Fisher over the past few years, and I am thankful for his willingness to help me with the many problems I have brought to him. I would like to give a special thanks to Ian Harry for his mentorship, and especially his patience. He taught me so much my first couple of years at Syracuse. Thanks to Ben Lackey and Laura Nuttall for their insight, comments, and collaboration on much of my work. I am thankful to have had the opportunity to work and share an office with TJ Massinger and Alex Nitz; they have set a high standard to aspire to. I have had a lot of help on many projects, and I would like to especially thank Larne Pekowsky, Soumi De, Daniel Finstad, Steven Reyes, Swetha Bhagwat, David Kelley, and Peter Couvares for all their contributions and time. Thanks to everyone from the PyCBC Group, the Hardware Injection Group, the Calibration Group, and the Hanford observatory that have shared their knowledge with me. Collin Capano has helped me accomplish so much these past few months, and I am extremely appreciative of all his comments and contributions. I am glad to have received the exceptional guidance of Eric Thrane, Mike Landry, and David Shoemaker. I would like to thank my fellow Fellows: Marissa Walker, Evan Goetz, v Elli King, Miquel Oliver, Jordan Palamos, and Vinnie Roma. It was a pleasure serving with you all at the Hanford observatory during the first observing run. For their help on various projects I would like to thank: Stuart Anderson, Joe Betzwieser, Miriam Cabero, Craig Cahillane, Mykyta Hulko, Sudarshan Karki, Jeff Kissel, Andy Lundgren, Duncan Macleod, Adam Mullavey, Keith Riles, Jamie Rollins, Rick Savage, Josh Smith, John Veitch, and Salvo Vitale. I would like to thank my committee members Duncan Brown, Liviu Movilenau, Carl Rosenzweig, Matt Rudolph, Peter Saulson, and Will Wyile for taking the time to review my dissertation. Finally, I would like to thank my parents. They have done so much for my brothers and me, and I owe so much to them. vi to Mom and Pops vii Contents Preface iv Acknowledgmentsv List of Tables xii List of Figures xxvi 1 Introduction1 1.1 Gravitational waves and binary black hole mergers...........1 1.2 Advanced LIGO..............................3 1.3 Advanced LIGO's first observing run..................5 2 The detection of binary black hole mergers in Advanced LIGO's first observing run8 2.1 Introduction................................8 2.2 Matched filter...............................9 2.3 Template bank.............................. 10 2.4 Data conditioning............................. 12 2.5 Signal-consistency test.......................... 12 2.6 Significance measurement........................ 14 2.7 Data selection............................... 16 2.8 Results................................... 17 2.9 Conclusions................................ 20 3 The impact of calibration errors on the detection of binary black hole mergers in Advanced LIGO data 33 viii 3.1 Introduction................................ 33 3.2 Models of the sensing function and actuation function......... 37 3.3 Simulating calibration errors in Advanced LIGO data......... 39 3.4 Derivation of the impact of calibration errors on the matched-filter signal-to-noise ratio............................ 42 3.5 Impact of calibration errors on the matched-filter signal-to-noise ratio of GW150914............................... 49 3.6 Impact of calibration errors on the matched-filter signal-to-noise ratio of binary neutron star and black hole mergers with a total mass up to 100 M .................................. 50 3.7 Impact of calibration errors on the detection statistic of GW150914. 51 3.8 Impact of calibration errors on the detection statistic of a simulated 30-30 M binary black hole merger................... 53 3.9 Conclusions................................ 53 4 A parameter estimation pipeline for binary neutron star and black hole mergers in Advanced LIGO data 73 4.1 Introduction................................ 73 4.2 Likelihood................................. 75 4.3 Priors................................... 78 4.4 Ensemble Markov-chain Monte Carlo sampling............. 84 4.5 emcee sampling algorithm........................ 87 4.6 kombine sampling algorithm....................... 89 4.7 The state of parameter estimation pipelines in Advanced LIGO's first and second observing runs........................ 91 4.8 Parameter estimation of binary black hole mergers from Advanced LIGO's first observing run........................ 93 4.9 Conclusions................................ 97 5 The capability of gravitational-wave observatories to probe the black hole mass gap due to pair-instability supernovae 104 5.1 Introduction................................ 104 5.2 Methods.................................. 105 5.3 Results................................... 108 ix 5.4 Conclusions................................ 110 6 The Advanced LIGO hardware injection system 120 6.1 Introduction................................ 120 6.2 Hardware injection procedure...................... 122 6.3 Binary black hole merger hardware injections............. 128 6.4 Loud hardware injections for detector characterization........ 136 6.5 Conclusions................................ 137 7 A pipeline for validating the Advanced LIGO hardware injection state information 139 7.1 Introduction................................ 139 7.2 Hardware injection state information.................. 140 7.3 Pipeline topology............................. 145 7.4 Conclusions................................ 145 8 Conclusions 148 Bibliography 151 x List of Tables 1 Table of measured time-dependent calibration parameter values for analysis time on September 15. 2015. The 90% percentile is the interval that contains 90% of the total samples. The change in the cavity pole frequency ∆fc is offset from the measured value of 341 Hz....... 50 2 Table of measured time-dependent calibration parameter
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