Since 2002 Perimeter Institute has been recording seminars, conference talks, and public outreach events using video cameras installed in our lecture theatres. Perimeter now has 7 formal presentation spaces for its many scientific conferences, seminars, workshops and educational outreach activities, all with advanced audio-visual technical capabilities. Recordings of events in these areas are all available On-Demand from this Video Library and on Perimeter Institute Recorded Seminar Archive (PIRSA). PIRSA is a permanent, free, searchable, and citable archive of recorded seminars from relevant bodies in physics. This resource has been partially modelled after Cornell University's arXiv.org.
Recently generated asymptotic expansions zanolin et al. arXiv:0912.0065 [gr-qc] showa frequentist approach to go beyond Fisher information assessments of the accuracy for maximum likelihood parameter estimations. In this talk we describe the application of these techniques to directional reconstruction fornumerical relativity waveforms.
Most searches with ground-based detectors for gravitational-wave signals from the inspirals of stellar-mass compact binaries use template based methods. Those work well for non-spinning systems but since the dimensionality of the parameter space of spinning waveforms is large a template bank search is not feasible. We describe Bayesian and Markov-chain Monte-Carlo methods for parameter estimation of spinning waveforms using hybrid spinning waveforms matching the ringdown from Numerical Relativity results.
Black hole-neutron star binary (BHNS) mergers are likely sources for detectable gravitational radiation and candidate engines for short-hard gamma-ray bursts. However, accurate modeling of these mergers requires fully general relativistic simulations, incorporating both relativistic hydrodynamics for the matter and Einstein's field equations for the (strong) gravitational fields. I will review techniques and results from recent fully general relativistic BHNS merger simulations.
The familiar post-Newtonian inspiral description of a binary neutron star system is sufficient for detection in current instruments. However, as we consider making astrophysical measurements using advanced detectors, the effects of matter and strong gravity on gravitational wave signals may become significant. I will review recent work modelling the waveforms produced by the inspiral and coalescence of binary neutron stars. In the mid-to-late inspiral this includes modifications to the post-Newtonian waveform models from tidal deformations.
A coherent multi-site search is expected to be more powerful than itscoincident counterpart in discriminating gravitational wave (GW) signals fromthe noise background. This is because the former tests the consistency of thesignals' amplitudes phases and time-delays across the sites with those expected from a real GW source. However the coherent statistic that is optimalin Gaussian noise is not guaranteed to perform as well in real data which arenon-Gaussian.
In this talk we present the motivation behind our implementation of and results from a coherent search for spinning compact binary coalescences. Our method uses the Physical template family of waveforms which describe binaries where only one of the objects has spin. In addition we discuss the possibility of extending thissearch to incorporate template waveforms for precessing black hole mergers derived from numerical relativity.
We present simulations of non-spinning unequal mass black-hole binaries with mass ratio q=1/4 covering approximately 11 orbits prior to coalescence and merger obtained with the moving puncture technique. Accuracy of the simulations and matching to post-Newtonian waveforms is discussed.