AN EFFICIENT APPROXIMATION TO THE LIKELIHOOD FOR GRAVITATIONAL WAVE STOCHASTIC BACKGROUND DETECTION USING PULSAR TIMING DATA

Journal Article · Mon May 20 04:00:00 EDT 2013 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/769/1/63· OSTI ID:22126599

Ellis, J. A.; Siemens, X. ^[1]; Van Haasteren, R. ^[2]

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1. Center for Gravitation, Cosmology and Astrophysics, University of Wisconsin Milwaukee, Milwaukee, WI 53211 (United States)
2. Max-Planck-Institut fuer Gravitationphysik (Albert-Einstein-Institut), D-30167 Hanover (Germany)

Direct detection of gravitational waves by pulsar timing arrays will become feasible over the next few years. In the low frequency regime (10{sup -7} Hz-10{sup -9} Hz), we expect that a superposition of gravitational waves from many sources will manifest itself as an isotropic stochastic gravitational wave background. Currently, a number of techniques exist to detect such a signal; however, many detection methods are computationally challenging. Here we introduce an approximation to the full likelihood function for a pulsar timing array that results in computational savings proportional to the square of the number of pulsars in the array. Through a series of simulations we show that the approximate likelihood function reproduces results obtained from the full likelihood function. We further show, both analytically and through simulations, that, on average, this approximate likelihood function gives unbiased parameter estimates for astrophysically realistic stochastic background amplitudes.

• OSTI ID: 22126599
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 1 Vol. 769; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
AMPLITUDES
APPROXIMATIONS
ASTROPHYSICS
DATA ANALYSIS
DETECTION
GRAVITATIONAL WAVES
PULSARS
SIMULATION
STOCHASTIC PROCESSES