Accession Number : AD0412295

Title :   MAGNETIC SCATTERING OF NEUTRONS.

Descriptive Note : Annual technical rept. no. 2, 1 Jan-31 Dec 62.

Corporate Author : KJELLER RESEARCH ESTABLISHMENT (NORWAY)

Report Date : 31 DEC 1962

Pagination or Media Count : 1

Abstract : A crystal spectrometer with f.c.c. cobalt crys tals was used for producing a polarized, mono energetic neutron beam. The polarizing efficiency of a number of crystals was tested and a maximum polarization of 0.975 = 0.015 was measured. Magnetic guide-fields were shaped such as to give minimum depolarization. A nuclear magnetic resonance unit was constructed and found to flip the neutron spins with an efficiency of 99%, this number being measured with an accuracy of 2.5%. With f.c.c. cobalt crystals both in polarizing and analyzing positions a double refl n ratio better than 25 was measured. This number is deemed suf ficiently high that the planned spin wave ex periments with polarized neutrons may be started. Collective spin excitations in f.c.c. cobalt were studied by scattering of unpolarized neu trons. The shape and intensity of diffuse peaks of neutrons scattered inelastically after absorbing phonon and magnon energies of 2.44 meV, were studied in the temperature range from 300 to 900 degrees K. Some details of the two experimental setups are given. (Author)

Descriptors :   (*NEUTRON SCATTERING, NUCLEAR), (*NEUTRON BEAMS, POLARIZATION), INELASTIC SCATTERING, NEUTRONS, SPINNING(MOTION), MAGNETIC, FIELDS, NUCLEAR RESONANCE, MONOCHROMATIC, CRYSTALS, CRYSTAL STRUCTURE, OSCIL, COILS, FREQUENCY SHIFT, SPECTROSCOPY, MAGNETOMETERS.

Distribution Statement : APPROVED FOR PUBLIC RELEASE