IRON(II) SULFATE (FRICKE SOLUTION) OXIDATION YIELDS FOR 8.9 AND 13.6 KEV X-RAYS FROM SYNCHROTRON RADIATION

The oxidation yields (G) for 8.86 and 13.55 keV X-rays produced by synchrotron radiation were measured using an iron(II) sulphate (Fricke) solution. Monoenergetic X-rays were produced using a silicon crystal monochromator. The X-rays were absorbed in 0.4 M sulphuric acid-iron(II) sulphate solution and Fe(III) ion yields were measured and corrected for escape fractions resulting from scattering using Monte Carlo calculations. Doses in the solution were determined using a thin window, parallel plate chamber calibrated against a primary standard free-air chamber at the Electrotechnical Laboratory (Osaka, Japan). Yields (G) of 1.50 +/- 0.06 and 1.43 0.06-mu-mol J-1 were obtained for 8.86 and 13.55 keV X-rays respectively.