Abstract
Ultrasonic attenuation and velocity have been studied above the 105K structural phase transition in SrTiO3. Two different samples, one Verneuil-grown, the other flux-grown, have been investigated. The data were analysed self-consistently to obey symmetry requirements and the Kramers-Kronig relations. Both samples possess the same power law behaviour for the measured quantities. The exponents are larger than the critical exponents predicted from renormalisation group theory. An order of magnitude difference in relaxation time amplitudes between the two samples is interpreted as being due to different impurity contents. In the flux-grown sample, first-order-like behaviour was observed.