Rapid Bayesian Triangulation of Gravitational Wave Inspirals for Advanced LIGO

Potential electromagnetic counterparts of compact binary mergers detectable by ground-based gravitational wave detectors fade rapidly. In the last joint LIGO--Virgo science run, a coincidence-based triangulation code produced sky maps for rapid telescope pointing. We are improving upon it with a more accurate Bayesian sky localization algorithm that takes as input the matched-filter amplitude and time-of-arrival. We review the parameter estimation accuracy of matched filters, comparing the often-used Cram\'{e}r-Rao bound with the tighter, but less well known, Barankin bound. We then describe our new sky localization algorithm and its performance.