INELASTIC SCATTERING OF SLOW NEUTRONS IN MODERATORS. PROCEEDINGS OF THE NEUTRON THERMALIZATION CONFERENCE, APRIL 28-30, 1958, GATLINBURG, TENNESSEE

Technical Report · Sat Oct 31 04:00:00 EST 1959

OSTI ID:4245583

Hughes, D J; Ghose, A M; Palevsky, H; Kienle, P

The details of the energy exchanges between slow neutrons and lattice vibrations are important in determining the manner in which moderation occurs and the neutron energy spectrum in different geometries. Measurements have been in progress for several years at Brookhaven in which the lattice vibrations are studied by means of the energy gain of incident cold neutrons. The cold neutrons, of energy 0.004 ev, are produced by filtration in cooled polycrystalline beryllium and the velocity of the scattered neutrons is determined by time of flight. For a single crystal of a coherent scattering material, the frequency of the phonons as a function of their wave number, i.e., the dispersion law, may be measured for both acoustical and optical vibrations. For incoherent scatterers the lattice vibration spectrum is obtained directly but not the detailed dispersion law. Measurements were made for a number of moderators, among which ZrH exhibits an intense optical lattice vibration at an energy of 0.134 ev. (auth)

• Research Organization: Brookhaven National Lab., Upton, N.Y.
• NSA Number: NSA-13-020340
• OSTI ID: 4245583
• Report Number(s): ORNL-2739(Paper III-A)
• Country of Publication: United States
• Language: English

Related Subjects

BERYLLIUM
CONFIGURATION
COOLING
CRYSTALS
ENERGY
ENERGY RANGE
EV RANGE
FILTERS
INELASTIC SCATTERING
LATTICES
MEASURED VALUES
MODERATORS
MONOCRYSTALS
NEUTRON SPECTROMETERS
PHONONS
PHYSICS AND MATHEMATICS
SCATTERING
SLOWDOWN
SPECTRA
THERMAL NEUTRONS
VELOCITY
VIBRATIONS
ZIRCONIUM HYDRIDES