COHERENT AND INCOHERENT-SCATTERING OF 42.75 AND 47.24 KEV X-RAY PHOTONS SCATTERED FROM AL, CU, Y, MO, AU AND PB

Using nearly monoenergetic unpolarized K alpha x-ray photons, measurements were made of the coherent and Compton scattered intensity in the atomic region 13 less than or equal to Z less than or equal to 82 at an angle of 90 degrees with a high-resolution Si(Li) detection system. In order to improve the efficiency of the detection system, the excitation source, detector and the sample assembly were placed in a vacuum chamber and a pressure of 10(-2) mbar was maintained throughout the measurements. Experimental scattering cross-sections are compared with the normalized integrated cross-sections based on form factor and incoherent scattering functions, Experimental coherent scattering cross-sections are higher than the theoretical values, indicating the resonance behaviour, fine structure effects and oscillation of coherent intensity around the absorption edges. Experimental incoherent scattering cross-sections are lower than the theoretical estimates for heavy elements, indicating the effect of electron binding at low photon energies.