FUNDAMENTAL-ASPECTS OF X-RAY PHOTOACOUSTIC PHENOMENA

The mechanism why extended X-ray absorption fine structure (EXAFS) is observed in X-ray photoacoustic spectra, has been discussed from vario us points of view, however, it is still unclear. We continued to gathe r many aspects of data of X-ray photoacoustic phenomena in order to so lve this question. Recently, we found EXAFS also in phase spectra of X -ray photoacoustic signal and related it with the signal shape. This p henomenon reflects the thermal depth depending on the absorption coeff icients, however, there are left still unresolved aspects. All aspects of the data are shown and discussed in relation to its mechanism.