Sequence estimation of piled-up pulses in synchrotron-based XAFS

Signal processing techniques are being developed that allow XAFS and diffraction experiments employing solid state detectors to be carried out at higher count rates by resolving shaper pulses that would otherwise be rejected or corrupted due to pile-up. This method exploits the time structure of the synchrotron generated radiation and a priori knowledge of the incident and fluorescence energies to perform sequence of event estimation based on periodically sampled observations of the shaper amplifier output. Isolated pulses are processed with a simple threshold decision much like an SCA while non-isolated pulses that produce sequence segments of finite length are processed as vectors. Once the vector is estimated, the number of fluorescence and scatter events is counted. Since these piled-up pulses are not rejected, the over all count rate of the experiment is increased.