TRANSVERSE X-RAY COHERENCE IN NUCLEAR-SCATTERING OF SYNCHROTRON-RADIATION

The time response of nuclei excited by pulsed synchrotron radiation is affected by correlations in the nuclear response transverse to the be am direction. The coherent addition of the radiation scattered by nucl ei having a distribution of Doppler shifts accelerates the decay in th e forward scattering from a rotating foil of Fe-57 stainless steel. A model based on Huygens's construction shows good agreement with the da ta, allowing estimation of the source size or transverse coherence len gth. Implications for spectroscopic experiments using nuclear forward scattering are discussed.