Efficient Optimal Reconstruction of Linear Fields and Band-powers from Cosmological Data

Understand

We present an efficient implementation of Wiener filtering of real-space linear field and optimal quadratic estimator of its power spectrum Band-powers.

• We first recast the field reconstruction into an optimization problem, which we solve using quasi-Newton optimization.
• We then recast the power spectrum estimation into the field marginalization problem, from which we obtain an expression that depends on the field reconstruction solution and a determinant term.
• We develop a novel simulation based method for the latter.