M-X-RAY-FLUORESCENCE CROSS-SECTIONS AND YIELDS IN THE ATOMIC REGION 8-LESS-THAN-OR-EQUAL-TO-Z-LESS-THAN-OR-EQUAL-TO-82 EXCITED BY 6.47 AND 7.57 KEV PHOTONS

Experimental M X-ray fluorescence cross sections for the elements Pt, Au and Pb have been measured at incident photon energies 6.47 and 7.57 keV. Theoretical M X-ray fluorescence cross sections for the elements Yb, W, Hg, Tl, Bi and Ra at 6.47 and 7.57 keV are also calculated. Ex perimental results are compared with the theoretical values based on r elativistic Dirac-Hartree Slater calculations of Chen ct al. and non-r elativistic calculations of McGuire. The average M shell fluorescence yields <(omega)over bar (M)>, have been deduced using experimental cro ss section values and the theoretical M shell photoionization cross se ctions. Results are compared with the available theoretical values.