Year: 2024
Type: article
Abstract: In this work, we investigate the optimal map-making technique for the linear system d = Ax + n while carefully taking into account singularities that may come from either the covariance matrix C = ⟨nn t ⟩ or the main matrix A. We first describe the general optimal solution, which is quite complex, and then use the modified pseudo inverse to create a near-optimal solution, which is simple, robust, and can significantly alleviate the unwanted noise amplification during map-making. The effectiveness of the nearly optimal solution is then compared to that of the naive co-adding solution and the standard pseudo inverse solution, showing noticeable improvements. Interestingly, all one needs to get the near-optimal solution with singularity is just a tiny change to the classical solution, which is designed for the case without singularity.
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
Awards: G4533563370, G7331079543
OpenAlex ID: W4393933113