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arXiv · astro-ph/9703084

Fast Spherical Harmonic Analysis: a quick algorithm for generating and/or inverting full sky, high resolution CMB Anisotropy maps

Pio Francesco Muciaccia·Paolo Natoli·Nicola Vittorio
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Abstract

We present a fast algorithm for generating full sky, high resolution ($\sim 5'$) simulations of the CMB anisotropy pattern. We also discuss the inverse problem, that of evaluating from such a map the full set of $a_{\ell m}$'s and the spectral coefficients $C_\ell$. We show that using an Equidistant Cylindrical Projection of the sky substantially speeds up the calculations. Thus, generating and/or inverting a full sky, high resolution map can be easily achieved with present day computer technology.

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Pio Francesco Muciaccia, Paolo Natoli, Nicola Vittorio. 1997-03-12. Fast Spherical Harmonic Analysis: a quick algorithm for generating and/or inverting full sky, high resolution CMB Anisotropy maps. https://doi.org/10.1086/310921

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