2008/07/28 by Charmaine Armitage-Caplan, Benjamin D. Wandelt · 3 citations
Earth and Planetary Sciences · Physics and Astronomy · #Adaptive optics and wavefront sensing #Advanced X-ray Imaging Techniques #Seismic Imaging and Inversion Techniques #astro-ph
paper · pdf · doi:10.1088/0067-0049/181/2/533
12 pages, 8 figures, submitted to ApJS. Full paper with high resolution figures is available at http://www.astro.uiuc.edu/~carmitag/prebeam/
arxiv created 2008/07/28 · openalex publication_date 2009/03/19 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/31
We describe a maximum-likelihood regularized beam deconvolution map-making algorithm for data from high-resolution, polarization-sensitive instruments, such as the Planck data set. The resulting algorithm, which we call PReBeaM, is pixel-free and solves for the map directly in spherical harmonic space, avoiding pixelization artifacts. While Fourier methods like ours are expected to work best when applied to smooth, large-scale asymmetric beam systematics (such as far-side lobe effects), we show that our m -truncated spherical harmonic representation of the beam results in negligible reconstruction error—even for m as small as 4 for a polarized elliptically asymmetric beam. We describe a hybrid OpenMP/MPI parallelization scheme which allows us to store and manipulate the time-ordered data from satellite instruments with a typical full-sky scanning strategy. Finally, we apply our technique to noisy data and show that it succeeds in removing visible power spectrum artifacts without generating excess noise on small scales.