Cosmology Without Windows: Quadratic Estimators for the Galaxy Power Spectrum

Understand

Conventional algorithms for galaxy power spectrum estimation measure the true spectrum convolved with a survey window function, which, for parameter inference, must be compared with a similarly convolved theory model.

• In this work, we directly estimate the unwindowed power spectrum multipoles using quadratic estimators akin to those introduced in the late 1990s.
• Under Gaussian assumptions, these are optimal and free from the leading-order effects of pixellization and non-Poissonian shot-noise.
• They may be straightforwardly computed given the survey data-set and a suite of simulations of known cosmology.