Gravitational-Wave Radiation from Merging Binary Black Holes and Supernovae
Total Page:16
File Type:pdf, Size:1020Kb
Gravitational-wave radiation from merging binary black holes and Supernovae I. Kamaretsos Submitted for the degree of Doctor of Philosophy School of Physics and Astronomy Cardiff University October 2012 Declaration of authorship • Declaration: This work has not previously been accepted in substance for any degree and is not concurrently submitted in candidature for any degree. Signed: :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: (candidate) Date: ::::::::::::::::::: • Statement 1: This thesis is being submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy (PhD). Signed: :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: (candidate) Date: ::::::::::::::::::: • Statement 2: This thesis is the result of my own independent work/investigation, except where otherwise stated. Other sources are acknowledged by explicit refer- ences. Signed: :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: (candidate) Date: ::::::::::::::::::: • Statement 3 I hereby give consent for my thesis, if accepted, to be available for photo- copying and for inter-library loan, and for the title and summary to be made available to outside organisations. Signed: :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: (candidate) Date: ::::::::::::::::::: i Summary of thesis This thesis is conceptually divided into two parts. The first and main part concerns the generation of gravitational radiation that is emitted from merging black-hole binary systems using Numerical Relativity methods. The second part presents the methodology of the search for gravitational-wave bursts that are emitted in core-collapse Supernovae. My approach to Numerical Relativity is to utilise the late-time gravitational radiation of merging binary black holes to extract key astrophysical parameters from such systems via standard parameter estimation techniques. I begin with an introductory chapter that outlines the standard theories of stationary and perturbed black holes. In addition, up-to-date techniques in performing binary black hole simulations, the current and near-future status of the global network of gravitational-wave detectors, as well as the most promising gravitational-wave sources. I conclude the chapter with elements on parameter estimation techniques, such as Bayesian analysis and the Fisher information matrix. In Chapter 2, I dis- cuss detection issues and parameter estimation results from the late-time radiation of colliding non-spinning black holes in quasi-circular orbits, and propose a prac- tical test of General Relativity, as well as of the nature of the merged compact object. Chapter 3 involves similar parameter extraction calculations, but involves a more realistic approach, whereby the effect of the various angular parameters on parameter estimation is considered, placing an emphasis on the actual science benefit from measuring the gravitational radiation from perturbed intermediate and supermassive black holes. In Chapter 4 we present the results of an extensive Numerical Relativity study of merging spinning black hole binaries and argue that the mass ratio and individual spins of a non-precessing progenitor binary can be measured solely by observing the late-time radiation. Chapter 5 presents the methodology in carrying out searches for gravitational- wave bursts (GWB) from core-collapse Supernovae with a dedicated for GWB searches pipeline (X-Pipeline) and presents the sensitivity performance of X- Pipeline in detecting GWBs associated with certain Supernova candidates during the two most recent LIGO-Virgo-GEO Science Runs. ii Contents 1 Introduction 1 1.1 Short treatment on black holes . .1 1.1.1 Black hole no-hair conjecture . .2 1.1.2 Different notions of black hole horizon . .4 1.2 Quasinormal modes of black holes . .6 1.2.1 Overview of BH quasinormal modes . .6 1.2.2 Brief history of BH QNMs . .7 1.2.3 Perturbative analysis of Kerr black holes . .7 1.3 Numerical Relativity . 12 1.3.1 3 plus 1 formulation of General Relativity . 12 1.4 The bifunctional adaptive mesh code for binary black hole evolution 13 1.4.1 Arnowitt-Deser-Misner mass . 14 1.4.2 Initial data for BBH simulations . 15 1.4.3 Gravitational waveform extraction . 17 1.4.4 Numerical calculation of Ψ4 and physical quantities . 20 1.4.5 Numerical calculation of the apparent horizon . 22 1.4.6 Convergence testing and credibility of the results . 24 1.5 Promising sources of gravitational radiation . 25 1.5.1 Compact Binary Coalescence . 25 1.5.2 Continuous waves . 29 1.5.3 Burst-like gravitational waves . 29 1.5.4 Other types of sources . 30 1.6 Global effort in detecting gravitational waves . 31 1.6.1 Ground-based interferometric detectors . 32 1.6.2 Space-based detectors . 36 1.6.3 Other ongoing efforts in detecting gravitational waves . 37 1.7 Parameter estimation from perturbed BHs . 38 1.7.1 Fisher matrix analysis . 38 1.7.2 Bayesian inference . 39 1.7.3 How Nested Sampling works . 41 2 Black-hole hair loss: learning about binary progenitors from ring- down signals 44 2.1 Introduction . 44 2.2 Numerical simulations of merger and ringdown signals . 48 2.3 Antenna response to a ringdown signal . 50 iii 2.4 Amplitudes of modes excited during the ringdown phase of a black hole binary . 55 2.4.1 Evolution of the luminosity . 57 2.4.2 Identifying the ringdown phase . 58 2.4.3 Relative amplitudes in the ringdown phase . 61 2.4.4 Fitting functions for relative amplitudes . 62 2.5 Visibility of ringdown modes . 63 2.5.1 Matched filter SNR . 64 2.5.2 Sensitivity curves . 65 2.5.3 Choice of various parameters . 66 2.5.4 Visibility of different modes . 68 2.5.5 Exploring black hole demographics with ET and LISA . 69 2.6 What can a ringdown signal measure? . 69 2.6.1 The full parameter set . 72 2.6.2 Measurements with a network of detectors . 73 2.7 Understanding mass loss, spin re-orientation and mass ratio from ringdown signals . 77 2.7.1 Mass ratio and component masses of the progenitor binary . 78 2.7.2 Mass loss to gravitational radiation . 79 2.7.3 Exploring naked singularities . 80 2.7.4 Spin orientations and the luminosity distance . 81 2.8 Parametrization for testing the no-hair theorem . 81 2.8.1 Maximal set . 83 2.8.2 Minimal set . 85 2.9 Conclusions and future work . 86 3 From black holes to their progenitors: A full population study in measuring black hole binary parameters from ringdown signals 89 3.1 Introduction . 90 3.2 Full population Analysis . 91 3.2.1 Chosen waveform . 92 3.2.2 The simulations . 93 3.2.3 The parameter space . 94 3.2.4 Choice of masses and mass ratios . 94 3.3 Signal detectability and Parameter estimation . 97 3.3.1 NGO . 99 3.3.2 Results for NGO . 99 3.3.3 Einstein Telescope and Advanced LIGO . 102 3.3.4 Results for ET and aLIGO . 102 3.4 Astrophysical implications . 103 3.4.1 Supermassive black holes . 103 3.4.2 Intermediate-mass black holes . 105 3.5 Conclusions . 107 iv 4 Is black-hole ringdown a memory of its progenitor? 108 4.1 Introduction . 108 4.2 Background . 109 4.3 Numerical results . 110 4.4 Interpretation . 113 4.5 Measurement . 114 4.6 Discussion . 115 5 Search for gravitational-wave bursts from core-collapse Super- novae with X-Pipeline 117 5.1 Outline of X-Pipeline . 118 5.2 Detector network formulation . 119 5.3 Event generation via time-frequency analysis . 122 5.4 Handling elliptically polarized waveforms . 122 5.4.1 Background noise rejection . 123 5.5 Supernovae triggers . 125 5.6 Gravitational waveforms for sensitivity analysis . 127 5.6.1 GWs from bar modes . 128 5.6.2 Piro waveforms . 130 5.6.3 Sine-gaussian waveforms . 132 5.6.4 Dimmelmeier waveforms . 134 5.6.5 Yakunin matter-generated waveforms . 134 5.6.6 Burrows-Ott acoustic mechanism waveforms . 136 5.6.7 M¨ullerthree-dimensional waveforms . 137 5.6.8 Numerical waveforms set for SN 2006iw . 138 5.7 X-Pipeline and coherent WaveBurst joint search . 138 5.7.1 Conditioning the waveforms . 138 5.7.2 Joint X-Pipeline and coherent WaveBurst search . 141 5.7.3 Translating the burst MDC injection procedure to X-Pipeline141 5.8 Sensitivity performance of X-Pipeline . 143 6 Discussion 147 v List of Figures 1.1 Screenshots from animations showing the evolution of apparent horizons in coalescing BH binaries [1, 2]. Left panel shows the last moments before the individual, yet highly non-spherical ap- parent horizons merge, while right panel depicts a highly deformed common apparent horizon, shortly after it is formed. 24 1.2 Aerial views of the LIGO detectors, which are spaced almost 10 msec of light travel time. Left panel is a picture of the Livingston detector, while right panel shows the Hanford detector. 32 1.3 Left panel depicts the continuously improving sensitivity of the iLIGO detectors throughout the various Science Runs. The design sensitivity was achieved in 2007. Right panel shows the dramatic increase in detection horizon and volume from iLIGO to aLIGO. 33 1.4 All panels depict various likelihood contours in the θ~ parameter space (which is here assumed to be two-dimensional), along with the corresponding values in the cumulative prior function X: .... 42 2.1 This plot shows the relative luminosities, or radiated power, in modes (2; 2); (3; 3); (4; 4), and (2; 1):Llm represent the luminosi- ties (in units c = G = 1 in which luminosity is dimensionless) and rlm denote the ratios rlm = Llm=L22: The different panels cor- respond to systems with different mass ratios as indicated in the panel. Note that as the mass ratio increases, the luminosity in each mode decreases but the amplitudes of all higher-order modes rela- tive to the (2; 2)-mode increase. We have omitted | both in the figure and in this work | the next most dominant modes, (5; 5), (3; 2), (4; 3), (6; 6) and (5; 4) as they are generally less than one percent as luminous as the (2; 2) mode.