A fast map-making preconditioner for regular scanning patterns

作者:Naess Sigurd K*; Louis Thibaut
来源:Journal of Cosmology and Astroparticle Physics, 2014, 2014(8): 045.
DOI:10.1088/1475-7516/2014/08/045

摘要

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.

  • 出版日期2014-8