The nuclear lighthouse effect: a new tool for high-resolution X-ray spectroscopy

Synchrotron radiation that is coherently scattered from a rotating ensemble of resonant nuclei acquires an angular deflection proportional to the nucl ear decay time. At sufficiently high rotational frequencies, the delayed ra diation is well separated from the direct beam so that its time spectrum ca n be recorded with a position sensitive detector. This has been demonstrate d employing nuclear resonant scattering of synchrotron radiation at the 23. 8-keV resonance of Sn-119. Further spectroscopic applications employing hig h-energy nuclear resonances around 80 keV are discussed. (C) 2001 Elsevier Science B.V. All rights reserved.