A report on the application of synchrotron radiation to low-angle scattering

The use of synchrotron radiation as an intense X-ray source for biological diffraction has only very recently been promoted into a long-term experimental programme. Here we report on some general and some detailed aspects of this development. In the case of small-angle studies on weakly scattering specimens at high time resolution, e.g. stroboscopic diffraction studies on muscle, the lack of X-ray sources of considerably higher brightness than from conventional X-ray generators has become limiting. As it has become technically impossible to pursue the development of rotating-anode tubes much further, the use of an electron synchrotron or storage ring with 100 to 1000 times higher brightness opens up the possibility not only of collecting much improved data but also of whole new ranges of experiments. A brief description is presented of the low-angle diffraction equipment currently in use at the synchrotron in Hamburg.