Attenuation correction of L-shell X-ray fluorescence computed tomography imaging

X-ray Fluorescence Computed Tomography （XFCT） is a widely-used experimental technique for inves- tigating the spatial distribution of elements in a sample. However, image reconstruction for this technique is more difficult than for transmission tomography, one problem being self-absorption. In this work, we make use of known quantities and unknown density of elements of interest to express unknown attenuation maps. The attenuation maps are added to the contribution value of the pixel in the Maximum Likelihood Expectation Maximization （MLEM） reconstruction method. Results indicate that the relative error is less than 14.1%, which shows that this method can effectively correct L-shell XFCT.