A study of the properties of beam guides for TXRF using synchrotron radiation

HÉCTOR JORGE SÁNCHEZ; MARÍA CECILIA VALENTINUZZI; CARLOS PÉREZ

Campinas, Brasil

Congreso; Reunión Anual de Usuarios de LNLS (RAU 2004); 2004

This work reports a study of the properties of beam guides for total reflection XRF analysis when synchrotron radiation is employed.             Several beam guides were made producing a set of several devices with different dimensions and materials. They were mounted on the TXRF station of the XRF beamline of the LNLS. Characteristic lines of standard samples of powder compounds were used as intensity monitor. By selecting different monochromatic energies, the transmitted flux of photons and the excitation intensity on the sample were measured as a function of the angle of incidence.             The angular scanning showed characteristic structures of transmitted photons due to the different orders of reflections inside the beam guides. Theoretical calculations reproduce the experimental data reasonably well.             Excellent limits of detection were obtained and a comparison with the ones obtained with standard SR-TXRF showed no differences.