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Analytical calculation of the solid angle subtended by a circular disc detector at a point cosine source

M. J. Prata
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Abstract

We derive analytical expressions for the solid angle subtended by a circular disc at a point source with cosine angular distribution ($f(μ)=μ/π$)under the sole condition that the disc lies in the half-space illuminated by the source ($μ\geq 0$). The expressions are given with reference to two alternative coordinate systems (S and S'), S being such that the z axis is parallel to the symmetry axis of the disc and S' such that the $z'$ axis is aligned with the source direction. Sample plots of the expressions are presented.

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M. J. Prata. 2003-08-07. Analytical calculation of the solid angle subtended by a circular disc detector at a point cosine source. https://doi.org/10.1016/j.nima.2003.10.098

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