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Multiple concentric annuli for characterizing spatially nonuniform backgrounds

James Theiler·Jeff Bloch
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Abstract

A method is presented for estimating the background at a given location on a sky map by interpolating the estimated background from a set of concentric annuli which surround this location. If the background is nonuniform but smoothly varying, this method provides a more accurate (though less precise) estimate than can be obtained with a single annulus. Several applications of multi-annulus background estimation are discussed, including direct testing for point sources in the presence of a nonuniform background, the generation of "surrogate maps" for characterizing false alarm rates, and precise testing of the null hypothesis that the background is uniform.

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James Theiler, Jeff Bloch. 1999-01-26. Multiple concentric annuli for characterizing spatially nonuniform backgrounds. https://doi.org/10.1086/307348

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