Application history
Since their discovery by Roentgen just over 100 years ago, X-rays have
been a powerful tool in research, industry and medicine. All facets of
X-ray research have been revolutionised by the use of synchrotron
radiation and the high brightness beams now available. The graph shows
the rapid increase in the brightness of X-ray beams available for
research, since the introduction of synchrotron radiation in the 1960's.
First generation synchrotron sources were high energy physics
accelerators, where the synchrotron radiation was an unwanted
by-product.
In the 1960s, physicists and chemists began to use the radiation from
several of these accelerators in a "parasitic mode". The second
generation of synchrotron radiation facilities, such as the Photon
Factory in Japan, were constructed expressly to provide synchrotron
X-rays for research.
Recently a third generation of facilities is being completed, for
example, the 7 GeV Advanced Photon Source in the USA, and are providing
even higher brightness X-ray beams, about 10,000 times higher than those
of the second generation.
Today's application
Synchrotron radiation has become an indispensable
tool in a wide range of research fields.
Using the intense UV, soft X-ray and hard X-ray beams produced at
synchrotron radiation facilities, scientists can: determine the
structure of materials and molecules, the electronic (chemical)
structure of surfaces and interfaces; analyse tiny trace element
concentrations in micron-sized regions; measure local molecular
structures in disordered systems eg solutions and catalysts; obtain 3-D
CAT scan images with micron resolution, and so on.
One of the first techniques to make use of synchrotron radiation was
X-ray crystallography: the determination of atomic structure from X-ray
diffraction data.
X-ray crystallography has historically been the primary tool used to
investigate the structure of matter: the atomic and crystal structures
of most materials have been determined using these techniques.
This structural knowledge is central to the development of many new
technologies, e.g. pharmaceuticals and nanotechnology.
Synchrotron radiation, because of the characteristics mentioned above,
has not only allowed the extension of conventional crystallographic
techniques to the investigation of new materials and macro-molecules,
but it has also facilitated major advances in the understanding of the
structure and dynamics of ceramics, superconductors, polymers and the
structure of surfaces and interfaces, even at the level of single layers
of molecules. |
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