INELASTIC NUCLEAR RESONANT SCATTERING WITH SUB-MEV ENERGY RESOLUTION

With an undulator-based synchrotron source and a tunable x-raf monochr omator, we produce an x-ray beam with a flux of 4X10(8) photons/s in a n energy bandwidth of 920+/-110 mu eV (Delta E/E approximate to 6.2X10 (-8)) at a photon energy of 14.4 keV. The tunability of the monochroma tor allows for a measurement of lattice excitations in alpha-Fe using the technique of inelastic nuclear resonant scattering from Fe-57. The phonon density-of-states are extracted from the measurement and compa red to the calculated phonon density-of-states derived from neutron-sc attering measurements. (C) 1997 American Institute of Physics.