Fig. 4
From: Algorithms for joint activity–attenuation estimation from positron emission tomography scatter
18×18-voxel simulation setup: a indices of detectors and voxels at their respective locations; b true and c initial μ-maps, respectively, in 1/cm; d true and e initial activity distributions, respectively, in arbitrary units; the initial activity distribution is used only for joint estimation (see the “n-algorithms for joint estimation” section). Human-sized phantom, axes scaled in cm