A fast map-making preconditioner for regular scanning patterns
Instrumentation and Methods for Astrophysics
2015-06-17 v2 Cosmology and Nongalactic Astrophysics
Abstract
High-resolution Maximum Likelihood map-making of the Cosmic Microwave Background is usually performed using Conjugate Gradients with a preconditioner that ignores noise correlations. We here present a new preconditioner that approximates the map noise covariance as circulant, and show that this results in a speedup of up to 400% for a realistic scanning pattern from the Atacama Cosmology Telescope. The improvement is especially large for polarized maps.
Cite
@article{arxiv.1309.7473,
title = {A fast map-making preconditioner for regular scanning patterns},
author = {Sigurd Næss and Thibaut Louis},
journal= {arXiv preprint arXiv:1309.7473},
year = {2015}
}
Comments
6 pages, 9 figures, accepted for publication in JCAP