In this schematic of a system for measuring the nuclear lighthouse
effect, the frequency spread of a beam of synchrotron light is narrowed
with a high heat load monochromator (HHLM), then the beam is physically
narrowed with a pair of collimator slits. Finally, the light strikes
a thin sample mounted inside a cylinder spinning at several thousand
revolutions each second. Sample atoms excited by the synchrotron light
emit x-rays as the cylinder turns, forming a sweeping beam reminiscent
of the optical beams projected by naval navigation lighthouses. Modulations
in the intensity of the x-ray beam that strikes the detector give physicists
information about the local environments of the emitting atoms.
Reported by: R. Röhlsberger et al., Physical Review Letters, 23
July 2001.
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