Showing papers by "W. C. Koehler published in 1981"

Magnetic form factor of metallic iron and nickel as seen by inelastic neutron scattering from phonons

Abstract: The magnetic form factors of iron and nickel have been studied by means of coherent inelastic vibrational scattering of polarized neutrons in high-symmetry directions for momentum transfers which are different from the reciprocal-lattice vectors. The vibrational scattering has been separated from other inelastic scattering processes, such as spin-wave scattering, by means of energy analysis on a triple-axis polarized-neutron spectrometer. In the case of iron we see definite departures from the interpolated elastic form factor, depending on the direction and magnitude of the scattering vector. In the case of nickel the inelastic form factor is identical, within experimental error, to the elastic form factor.

The National Center for Small-Angle Scattering Research

Abstract: The National Center for Small-Angle Scattering Research is a user-dedicated facility supported by the National Science Foundation and the Department of Energy under an interagency agreement. The two main facilities available to users are the NSF constructed 30-m small-angle neutron scattering instrument (SANS) and the 10-m DOE constructed small-angle x-ray scattering camera (SAXS). Test measurements carried out on ATPase in H2O and in D2O buffer indicate that the SANS facility is capable of providing meaningful data on a wide variety of biological systems. Details of work carried out on the instrument by Uberbacher, Olins, and Bunick, on the binding of HMG proteins to nucleosomes, are presented in a separate poster. (Research sponsored by the National Science Foundation under interagency agreement No. 40-637-77 under Union Carbide Corporation contract W-7405-ENG-26 with the U.S. Department of Energy.)