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.
@article{arxiv.2009.11845,
title = {Improved reconstruction of a stochastic gravitational wave background with LISA},
author = {Raphael Flauger and Nikolaos Karnesis and Germano Nardini and Mauro Pieroni and Angelo Ricciardone and Jesús Torrado},
journal= {arXiv preprint arXiv:2009.11845},
year = {2021}
}