One of the interesting means the physicists article focuses on is the use of proton-induced x-ray emission (PIXE), which allows for a non-destructive study of art objects.

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There are, however, no interference problems with field-emission X-ray sources, so these can be used to take high-resolution pictures while treatment is proceeding.

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What you would see, says Fender, is emission in the x-ray, radio, infrared or optical.

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