APS Synchrotron Techniques
The unique properties of synchrotron radiation are its continuous
spectrum, high flux and brightness, and high coherence, which make
it an indispensable tool in the exploration of matter. The
wavelengths of the emitted photons span a range of dimensions from
the atomic level to biological cells, thereby providing incisive
probes for advanced research in materials science, physical and
chemical sciences, metrology, geosciences, environmental sciences,
biosciences, medical sciences, and pharmaceutical sciences. The
features of synchrotron radiation are especially well matched to the
needs of nanoscience.
This breadth of problems requires an extensive suite of probes.
The basic components of a beamline, however, share general
similarities as shown in the schematic diagram below.
The fundamental parameters that we use to perceive the physical
world (energy, momentum, position, and time) correspond to three
broad categories of synchrotron experimental measurement techniques:
spectroscopy, scattering, and imaging. By exploiting the short pulse
lengths of synchrotron radiation, each technique can be performed in
a timing fashion.
Spectroscopy
is used to study the energies of particles that are emitted or
absorbed by samples that are exposed to the light-source beam and
is commonly used to determine the characteristics of chemical
bonding and electron motion.
Scattering
makes use of the patterns of light produced when x-rays are
deflected by the closely spaced lattice of atoms in solids and is
commonly used to determine the structures of crystals and large
molecules such as proteins.
Imaging
techniques use the light-source beam to obtain pictures with fine
spatial resolution of the samples under study and are used in
diverse research areas such as cell biology, lithography, infrared
microscopy, radiology, and x-ray tomography.
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