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arXiv · 2101.02713

Measuring the primordial gravitational wave background in the presence of other stochastic signals

Abstract

Standard methodologies for the extraction of the stochastic gravitational wave background (SGWB) from auto- or cross-correlation of interferometric signals often involve the use of a filter function. The standard optimal filter maximizes the signal-to-noise ratio (SNR) between the total SGWB and the noise. We derive expressions for the optimal filter and SNR in the presence of a target SGWB plus other unwanted components. We also generalize the methodology to the case of template-free reconstruction. The formalism allows to easily perform analyses and forecasts that marginalize over foreground signals, such as the typical $Ω_{\rm GW} \propto f^{2/3}$ background arising from binary coalescence. We demonstrate the methodology with the LISA mission and discuss possible extensions and domains of application.

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Davide Poletti. 2021-06-15. Measuring the primordial gravitational wave background in the presence of other stochastic signals. https://doi.org/10.1088/1475-7516%2F2021%2F05%2F052

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