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arXiv · 2009.11845

Improved reconstruction of a stochastic gravitational wave background with LISA

Raphael Flauger·Nikolaos Karnesis·Germano Nardini·Mauro Pieroni·Angelo Ricciardone·Jesús Torrado
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Abstract

We present a data analysis methodology for a model-independent reconstruction of the spectral shape of a stochastic gravitational wave background with LISA. We improve a previously proposed reconstruction algorithm that relied on a single Time-Delay-Interferometry (TDI) channel by including a complete set of TDI channels. As in the earlier work, we assume an idealized equilateral configuration. We test the improved algorithm with a number of case studies, including reconstruction in the presence of two different astrophysical foreground signals. We find that including additional channels helps in different ways: it reduces the uncertainties on the reconstruction; it makes the global likelihood maximization less prone to falling into local extrema; and it efficiently breaks degeneracies between the signal and the instrumental noise.

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Raphael Flauger, Nikolaos Karnesis, Germano Nardini, Mauro Pieroni, Angelo Ricciardone, Jesús Torrado. 2021-02-16. Improved reconstruction of a stochastic gravitational wave background with LISA. https://doi.org/10.1088/1475-7516%2F2021%2F01%2F059

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