LIGO Gravitational Wave Data Analysis

In this decade, a number of interferometric gravitational wave observatories will come online at various sites around the world. General relativity predicts that violent astrophysical events will emit gravitational radiation - "ripples in space-time" - that will produce tiny but measurable changes in the relative path length of two perpendicular optical cavities. The difficulty of confidently detecting these small changes amid relatively large instrumental noise makes the combination of data from multiple observatories around the globe desirable. The relative locations and orientations of these detectors has implications for the sensitivity of the network as a whole; we seek to understand this interaction, and in particular how an Australian detector would improve the network.

Principal Investigator

David McClelland
Department of Physics
Faculty of Science
The Australian National University



Facilities Used



Philip Charlton
Benedict Cusack
John Ringland
Susan Scott
Antony Searle
Bram Slagmolen
Department of Physics
Faculty of Science
The Australian National University

Ben Evans
ANU Supercomputer Facility
The Australian National University

RFCD Codes

240101, 240201

Significant Achievements, Anticipated Outcomes and Future Work

The optimal placement and orientation for a new gravitational wave detector has been determined under several criteria, including a detection rate of binary inspiral events for implementations of two leading network analysis techniques. It has been demonstrated that under these criteria the siting of an observatory in Western Australia (Figure 1) is desirable. These results have been presented to the Fourth Edoardo Amaldi Conference and the 2001 Gravitational Wave Data Analysis Workshop. We will extend our analysis to consider the angular resolution of networks and detection rates of other source types.

Figure 1 - The relative merit of locations for a new observatory to augment the existing LIGO (North America) and VIRGO (Europe) observatories (lighter is better).


Computational Techniques Used

Monte-Carlo simulations of gravitational wave sources have been implemented in the MATLAB linear algebra package. The algorithm is amenable to parallelisation.


Publications, Awards and External Funding

A. C. Searle, S. M Scott, D. E. McClelland, Network Sensitivity to Geographical Configuration, Classical and Quantum Gravity, 2001 (accepted for publication).