Neutron thermalization as a fluctuation of the nonequilibrium steady state
The neutron thermalization problem has been reconsidered as a fluctuation of a steady state in an absorbing medium. If energy dependent neutron density distributions are chosen as random variables, the thermalization process can be treated as a Markoffian random process in which an incompletely thermalized neutron field approaches the steady state. It is shown that the thermalization matrix corresponds to the first moment-drift vector-, and that the diffusion constant is represented by a generalized Einstein relation. Since the loss of energy of the neutron per collision with a heavy moderator nucleus is very small in the thermalization pr alpha cess, the Smoluchowski integral equation is converted into the Fokker-- Planck equation. The quasi-Onsager reciprocal relation is obtained with respect to the steady state of the neutron thermalization process, in which neutrons are supplied, scattered and captured. (auth)
- Research Organization:
- Tohoku Univ., Sendai
- NSA Number:
- NSA-29-019603
- OSTI ID:
- 4312363
- Journal Information:
- Jap. J. Appl. Phys., v. 12, no. 10, pp. 1611-1620, Other Information: Orig. Receipt Date: 30-JUN-74; Bib. Info. Source: JA (JA)
- Country of Publication:
- Japan
- Language:
- English
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