Abstract

The LIGO and Virgo observatories have identified nearly a hundred gravitational wave signals from compact binary mergers. These detections, and their astrophysical interpretation, are only possible due to sophisticated data analysis algorithms. In this seminar I will overview a series of independent analyses of public LIGO –Virgo data by our group, going the way from the raw strain data to the characterization of the astrophysical population of merging compact objects. This involves identifying signals in noisy data, estimating their source parameters, and using the aggregated set of detections to test and inform models of the population. We developed a search pipeline that improved the sensitivity by rigorously accounting for inherent systematics. I will overview some of its salient features and highlight recent results, whereby we confirmed previous events and identified 19 new ones. These sources are characterized by 15 parameters, whose estimation is computationally challenging. I will introduce a set of analytic, invertible coordinate transformations that facilitate this task by removing several degeneracies and multimodalities typically encountered. Finally, I will show that the observed distribution of black hole spin orientations is anisotropic, disfavoring dynamical formation channels as the only pathway for merging binary black holes.