NEUTRON DIFFUSION STUDIES FOR WATER AND ICE AT TEMPERATURES NEAR 0 AND -80 C

Journal Article · Mon Oct 01 04:00:00 EDT 1962 · At. Energ. (USSR)

OSTI ID:4767885

Antonov, A V; Granatkin, B V; Merkul'ev, Yu A; Puzanov, V V; Smolik, Ch K

Interaction of the neutrons with a given moderator material depends not only on the neutron energy and the moderator temperature but also on the latter's state of aggregation. For this reason the behavior of the coefficient of diffusion D and the coefficient of diffisuon cooling C were investigated at the water--ice transition point and at --80 deg C by means of the nonstationary diffusion pulse method. It was assumed that the neutron lifetime in water is 204 mu sec and in ice, 222 mu sec. The ratios obtained for D, C, and D/sup 2//C, which defines the energy exchange between the neutron gas and the moderator, for ice and water were found to be 1.0 plus or minus 0.02, 2.50 plus or minus 0.40, and 0.43 plus or minus 0.09, respectively. This indicates that the diffusion coefficient is 4% larger in ice although it should be 1.09 in view of the 9% high density of water; the difference might be due to the fact that the average cosine of the neutron scattering angle, cos THETA , of the water either does not change or it decreases at the water--ice transition. At that time C increases 2.5 times and the D/sup 2//C of the ice increases by 43% with respect to that of water at 0 deg . Lowering the temperature results in the decrease of the values of D, C, and D/sup 2//C, indicating an increase of the thermalization time. (TTT)

• Research Organization: Originating Research Org. not identified
• NSA Number: NSA-17-002211
• OSTI ID: 4767885
• Journal Information: At. Energ. (USSR), Journal Name: At. Energ. (USSR) Vol. Vol: 13
• Country of Publication: Country unknown/Code not available
• Language: Russian

Related Subjects

ANGULAR DISTRIBUTION
COOLING
DENSITY
DIFFUSION
ENERGY
ICE
INTERACTIONS
LIFETIME
MELTING POINTS
MODERATORS
NEUTRONS
PHYSICS
PULSES
SCATTERING
SLOWDOWN
TEMPERATURE
WATER