Towards lowlatency realtime detection of gravitational waves from compact binary coalescences in the era of advanced detectors
Abstract
Electromagnetic (EM) followup observations of gravitational wave events will help shed light on the nature of the sources, and more can be learned if the EM followups can start as soon as the gravitational wave event becomes observable. In this paper, we propose a computationally efficient timedomain algorithm capable of detecting inspiral gravitational waves from coalescing binaries of compact objects with nearly no further delay in addition to the time required to condition the data into a time series of calibrated gravitationalwave strain. Our algorithm, if can be expanded to include sky localization, will serve as the first step towards triggering EM observation before the merger. The key to the efficiency of our algorithm arises from the use of chains of socalled infinite impulse response filters, which filter timeseries data recursively. Computational cost is further reduced by a template interpolation technique that requires filtering only done for a “coarse bank”, much sparser than the “fine bank” normally required to sufficiently recover the optimal signaltonoise ratio: the filter chain of each coarsebank template is divided into several sections, filtering output from these sections are combined appropriately to reconstruct the output of each of the nearby finebank templates. The filter construction and interpolation techniques are illustrated in this paper using Newtonianchirp waveforms, although these will be generalizable to more accurate postNewtonian waveforms. Towards future detectors with sensitivity extending to lower frequencies, our algorithm’s computational cost is shown to increase rather insignificantly compared to the conventional timedomain correlation method using finite impulse response filters.
 Publication:

Physical Review D
 Pub Date:
 May 2012
 DOI:
 10.1103/PhysRevD.85.102002
 arXiv:
 arXiv:1108.3174
 Bibcode:
 2012PhRvD..85j2002L
 Keywords:

 04.80.Nn;
 95.75.z;
 97.60.Gb;
 97.80.d;
 Gravitational wave detectors and experiments;
 Observation and data reduction techniques;
 computer modeling and simulation;
 Pulsars;
 Binary and multiple stars;
 General Relativity and Quantum Cosmology
 EPrint:
 19 pages, 6 figures, for PRD