Graduate Student Research Day 2010 Florida Atlantic University

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Graduate Student Research Day 2010 Florida Atlantic University CHARLES E. SCHMIDT COLLEGE OF SCIENCE Improvements to Moving Puncture Initial Data and Analysis of Gravitational Waveforms using the BSSN Formalism on the BAM Code George Reifenberger Charles E. Schmidt College of Science, Florida Atlantic University Faculty Advisor: Dr. Wolfgang Tichy Numerical relativity has only recently been able to simulate the creation of gravitational wave signatures through techniques concerning both the natural complexities of general relativity and the computational requirements needed to obtain significant accuracies. These gravitational wave signatures will be used as templates for detection. The need to develop better results has divided the field into specific areas of code development, one of which involves improvement on the construction of binary black hole initial data. Gravitational waves are a prediction of general relativity, however none have currently been observed experimentally. The search for gravitational wave signatures from binary black hole mergers has required many sub-disciplines of general relativity to contribute to the effort; numerical relativity being one of these. Assuming speeds much smaller than the speed of light Post-Newtonian approximations are introduced into initial data schemes. Evolution of this initial data using the BSSN formalism has approximately satisfied constraint equations of General Relativity to produce probable gravitational wave signatures. Analysis of data convergence and behavior of physical quantities shows appropriate behavior of the simulation and allows for the wave signatures to be considered for template inclusion. High order convergence of our data validates the accuracy of our code, and the wave signatures produced can be used as an improved foundation for more physical models. .

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