A number of the qualification and production witness samples are being set aside for precise reflectivity measurements at the Brookhaven National Laboratory (BNL) synchrotron. Time has been planned at BNL over the next four years to provide detailed measurements of reflectivity as a function of energy. These measurements will be used to determine the effective optical constants of the iridium and the true thicknesses of the sputtered layers. This program will be the subject of a future newsletter article.
