Measuring the primordial gravitational wave background in the presence of other stochastic signals. Issue 5 (19th May 2021)

• Record Type: Journal Article
• Authors: Poletti, D.
• Is Part Of: Journal of cosmology and astroparticle physics. Volume 2021:Issue 5(2021)
• Publication Date: 2021-05-19
• Subjects: gravitational waves / experiments -- gravitational wave detectors -- inflation -- primordial gravitational waves (theory); Cosmology -- Periodicals; Astrophysics -- Periodicals; 523.0105
• DOI: 10.1088/1475-7516/2021/05/052
• Languages: English
• ISSNs: 1475-7516

Abstract

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 ΩGW ∝ f 2/3 background arising from binary coalescence. We demonstrate the methodology with the LISA mission and discuss possible extensions and domains of application.