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arXiv · 1504.04485

Imaging on a Sphere with Interferometers: the Spherical Wave Harmonic Transform

T. D. Carozzi
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Abstract

I present an exact and explicit solution to the scalar (Stokes flux intensity) radio interferometer imaging equation on a spherical surface which is valid also for non-coplanar interferometer configurations. This imaging equation is comparable to $w$-term imaging algorithms, but by using a spherical rather than a Cartesian formulation this term has no special significance. The solution presented also allows direct identification of the scalar (spin 0 weighted) spherical harmonics on the sky. The method should be of interest for future multi-spacecraft interferometers, wide-field imaging with non-coplanar arrays, and CMB spherical harmonic measurements using interferometers.

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T. D. Carozzi. 2015-04-17. Imaging on a Sphere with Interferometers: the Spherical Wave Harmonic Transform. https://doi.org/10.1093/mnrasl/slv052

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