How x-ray diffraction with synchrotron radiation got started

The need to record low angle scattering x-ray fibre diagrams from muscle with milli-second time resolution drove the use of synchrotron radiation as an x-ray light source. The first smudgy diffraction patterns were obtained from a slice of insect flight muscle. Out of this grew the EMBL Outstation at DESY.

Bunker 4

The experimental facility at DORIS was housed in a small experimental hall rather than a bunker. Nevertheless, it was known as "Bunker-4". Duly equipped with offices, seminar room, workshops, and a biochemistry laboratory this building became the home of the EMBL Outstation in 1975. DORIS is a colliding beam facility with electron and positrons circulating in opposite directions. The beams into the EMBL bunker were from the positron ring. The first beam-line set up (X11, designed by G. Rosenbaum and A. Harmsen, later taken over by H. Bartunik) was a mirror-monochromator combination with 8x20cm mirrors and a bent germanium monochromator (Rosenbaum, 1979; Rosenbaum & Holmes, 1980). The bench carrying the specimen and detector could be rotated around the monochromator as pivot so as to vary the wavelength. Each of the mirrors could be individually bent. The electron beam in DORIS was considerably larger in cross-section than that of DESY so that fine-focused beams such as were obtained on the DESY synchrotronwere not attainable. In fact it turned out that although each of the mirrors was designed to be individually bent it was not really worth bending the mirror segments at all, aligning them appropriately without bending produced as fine a beam as one could get. A second optical system X13 (Bordas et al ., 1980) similar in design to X11 was soon added. The two shared a common mirror box and mirror design. These beam lines were the workhorses of the DORIS facility for a number of years. The EMBL Outstation in Bunker-4 expanded steadily and became one of the most widely used biological facilities in the world.

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