EVALUATION OF A SCATTERED RADIATION-FIELD IN A CLUSTER RELEVANT FOR MULTIPLE-ENERGY X-RAY HOLOGRAPHY

We analyze theoretically multiple-energy X-ray holography (MEXH), a ne w tool for material structure determination, already tested experiment ally, which utilizes synchrotron radiation to generate an electromagne tic scattering field at a specific target atom inside a material sampl e. In MEXH the target atom is considered as a detector, which indicate s the electric field strength at its core via the measurement of the t otal intensity of fluorescence that the atom emits in all directions. The modulations of the intensity, upon varying the direction and the e nergy of the incident synchrotron radiation, are registered as a holog ram which offers then the image of the environment surrounding the tar get atom. The purpose of this work is to determine theoretically the r elevant physical quantity of the process, i.e. the electromagnetic fie ld, at the target atom position. For this purpose we use methods of qu antum electrodynamics (QED). We obtain formulas which are interpreted in terms of a holographic description of the process which can then ha ve a direct experimental application through the MEXH method.