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A series solution and a fast algorithm for the inversion of the spherical mean Radon transform

Leonid Kunyansky
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Abstract

An explicit series solution is proposed for the inversion of the spherical mean Radon transform. Such an inversion is required in problems of thermo- and photo- acoustic tomography. Closed-form inversion formulae are currently known only for the case when the centers of the integration spheres lie on a sphere surrounding the support of the unknown function, or on certain unbounded surfaces. Our approach results in an explicit series solution for any closed measuring surface surrounding a region for which the eigenfunctions of the Dirichlet Laplacian are explicitly known - such as, for example, cube, finite cylinder, half-sphere etc. In addition, we present a fast reconstruction algorithm applicable in the case when the detectors (the centers of the integration spheres) lie on a surface of a cube. This algorithm reconsrtucts 3-D images thousands times faster than backprojection-type methods.

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Leonid Kunyansky. 2007-01-08. A series solution and a fast algorithm for the inversion of the spherical mean Radon transform. https://doi.org/10.1088/0266-5611%2F23%2F6%2Fs02

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