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arXiv · 2111.11240

Multi-Resolution HEALPix Maps for Multi-Wavelength and Multi-Messenger Astronomy

I. Martinez-Castellanos·Leo P. Singer·E. Burns·D. Tak·Alyson Joens·Judith L. Racusin·Jeremy S. Perkins
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Abstract

HEALPix -- the Hierarchical Equal Area isoLatitude Pixelization -- has become a standard in high-energy and gravitational wave astronomy. Originally developed to improve the efficiency of all-sky Fourier analyses, it is now also utilized to share sky localization information. When used for this purpose the need for a homogeneous all-sky grid represents a limitation that hinders a broader community adoption. This work presents mhealpy, a Python library able to create, handle and analyze multi-resolution maps, a solution to this problem. It supports efficient pixel querying, arithmetic operations between maps, adaptive mesh refinement, plotting and serialization into FITS -- Flexible Image Transport System -- files. This HEALPix extension makes it suitable to represent highly resolved regions, resulting in a convenient common format to share spatial information for joint multi-wavelength and multi-messenger analyses.

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I. Martinez-Castellanos, Leo P. Singer, E. Burns, D. Tak, Alyson Joens, Judith L. Racusin, Jeremy S. Perkins. 2021-11-22. Multi-Resolution HEALPix Maps for Multi-Wavelength and Multi-Messenger Astronomy. https://doi.org/10.3847/1538-3881%2Fac6260

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