Ž . Spectrochimica Acta Part B 56 2001 455464 Photon-induced M-shell X-ray production cross-sections and fluorescence yields in heavy elements at 5.96 keV  ¨ Rıdvan Durak , Yuksel Ozdemir ¨ ¨ Ataturk Uni  ersitesi, Fen Edebiyat Fakultesi, Fizik Bolumu, 25240 Erzurum, Turkey ¨ ¨ ¨¨ ¨ Received 19 September 2000; accepted 11 March 2001 Abstract Ž . Total M-shell X-ray production cross-sections MXRP for selected heavy elements between Yb and U at have Ž . been measured at 5.96 keV incident photon energy using a Si Li detector. The average M-shell fluorescence yields have been derived, using the experimental total M X-ray production cross-sections and theoretical M-shell photoionization cross-sections. Extracted cross-sections and fluorescence yields have been compared with the literature experimental values, theoretical predictions and semiempirical fits.  2001 Elsevier Science B.V. All rights reserved. Keywords: X-Ray fluorescence; Cross-sections; Photoionization; Fluorescence yields 1. Introduction Reliable values of experimental M X-ray pro- Ž . duction MXRP cross-sections and fluorescence yields are required in an increasing number of applications, such as chemical analysis by particle  Corresponding author. Fax: 90-442-2331062. Ž . E-mail address: rdur@rocketmail.com R. Durak . Ž . induced X-ray emission PIXE , X-ray fluores- Ž . cence XRF , dosimetric computation for health physics, basic studies of nuclear and atomic physics and industrial irradiation processing. Also, a comparison of measured MXRP cross sections with theoretical estimates provides a check on physical parameters such as M-shell photoioniza- tion cross-sections, fluorescence yields, Coster  Kronig transition probabilities and radia- tive decay rates. Most of the available experimen- 0584-854701$ - see front matter  2001 Elsevier Science B.V. All rights reserved. Ž . PII: S 0 5 8 4 - 8 5 4 7 01 00178-1