Investigate the gridded interferometric power-spectrum estimator more thoroughly

Investigate more thoroughly the gridded interferometric power-spectrum estimator, including the effects of its approximations and assumptions on normalization, decorrelation, mode mixing, and power-spectrum accuracy.

Background

The derived normalization for the gridded power spectrum relies on a first-order Taylor expansion of the cosmological power spectrum, an approximately constant power spectrum and gradient within each grid cell, and Gaussian primary beams. The authors note that the approximation performs better for small grid sizes and that the estimator is consequently a complex problem.

Because the paper focuses on foreground removal rather than parameter estimation, residual normalization biases are neglected in the main analysis. A more comprehensive investigation of the estimator is explicitly left unresolved.