Primary recoil distributions and specific damage energies have been computed for high energy deuteron-breakup neutrons in Cu, Nb, and Au. The calculations are based on theoretical neutron cross sections, and consider in particular a d-Be spectrum broadly peaked at 15 MeV with some neutrons above 30 MeV. The theoretical results are similar to corresponding calculations for monoenergetic 15-MeV neutrons and are in good agreement with range measurements of (n,2n) recoils generated by high energy d-Be neutrons in Nb and Au. The calculations are also consistent with recent d-Be neutron sputtering experiments in Nb and Au and demonstrate the usefulness of deuteron-breakup neutron sources for simulating fusion neutron effects. (auth)

It is shown that a strong lower hybrid wave is modulationally unstable to perturbations propagating along its own wave vector. The instability relies critically on the finite thermal corrections to the lower hybrid dispersion relation. (auth)

A status report of microinstability as it applies to 2XIIB and MX theory for mirror machines is presented. It is shown that quasilinear computations reproduce many of the parameters observed in the 2XIIB experiment. In regard to large mirror machines, there are presented detailed calculations of the linear theory of the drift cyclotron loss-cone mode, with inhomogeneous geometry and nonlinear diffusive effects. Further, the stability of a mirror machine to the Alfven ion-cyclotron instability is assessed, and the Baldwin- Callen diffusion is estimated for a spatially varying plasma. (auth)

The creepdown and collapse study on Zircaloy fuel cladding is concerned with the deformation behavior of cladding under normal and near-normal reactor operating conditions. Progress is reported on two phases of the program: (1) collapse testing and (2) development and fabrication of deformation-monitoring equipment. Sufficient collapse testing has been done to begin the analysis of the test data. It is apparent that all three of the independent variables used in this study (pellet-to-pellet gap, pellet-to-cladding gap, and temperature) play major roles in the collapse phenomenon. Tentative trends are presented but they constitute an insufficient basis for the quantitative formulation of a collapse model at this time. The instrumentation for deformation monitoring has been developed and provision has been made for automatic control of the data gathering system and for protection of the monitoring coils from damage caused by collapse of the specimen tube.

The neutron detection efficiency is a parameter required in the measurement of reactivity by the modified source technique. The direct solution of the detection efficiency at a perturbed state is costly. To solve for this, a particular variational functional, the Lewins' type variational functional, is presented. The functional is a ratio of two other functionals, each dealing with a reaction rate. The evaluation of this particular functional was done by treating the numerator and the denominator functionals separately. This leads to three flux equations, one for forward flux, and two for adjoint fluxes. The advantages of this formulation over, and the equivalence of this formulation to, the conventional functional presented in the literature are described in detail. The flexibility of the proposed functional is demonstrated by using it to estimate the detection efficiency with four different methods: variational interpolation, conventional variational, variational extrapolation, and multi- reference-state variational. Results are presented for one-dimensional and two- dimensional problems. All results are compared with direct calculations. In all cases, the results show that the variational interpolational method and the multi- reference-state variational method are efficient and practically acceptable.

Visible, ultraviolet, and infrared optical emission results from low- energy (20 eV-10 keV) particle-surface collisions. Several distinct kinds of collision induced optical radiation are discussed which provide fundamental information on particle-solid collision processes. Line radiation arises from excited states of sputtered surface constituents and backscattered beam particles. This radiation uniquely identifies the quantum state of sputtered or reflected particles, provides a method for identifying neutral atoms sputtered from the surface, and serves as the basis for a sensitive surface analysis technique. Broadband radiation from the bulk of the solid is attributed to the transfer of projectile energy to the electrons in the solid. Continuum emission observed well in front of transition metal targets is believed to arise from excited atom clusters (diatomic, triatomic, etc.) ejected from the solid in the sputtering process. Application of sputtered atom optical radiation for surface and depth profile analysis is demonstrated for the case of submonolayer quantities of chromium on silicon and aluminum implanted in SiO$sub 2$.

Differential cross sections for the neutron-induced gamma-ray production from copper have been measured for incident neutron energies between 0.2 and 20.0 MeV. The Oak Ridge Linear Accelerator (ORELA) was used to provide the neutrons and a NaI spectrometer to detect the gamma rays at 125$sup 0$. The data presented are the doubly differential cross section, d$sup 2$sigma/d$Omega$dE, for gamma-ray energies between 0.3 and 10.6 MeV for coarse intervals in incident neutron energy. The integrated yield of gamma rays of energies greater than 300 keV with higher resolution in the neutron energy is also presented. The experimental results are compared with previous measurements made at ORELA and with the Evaluated Neutron Data File (ENDF/B-IV, MAT 1295). 41 figures, cross section tables. (auth)

Research progress is briefly reported for the following tasks: reheater and steam generator model development, development of the nuclear steam supply system simulation code, core simulation for enemergency cooling analysis, core auxiliary cooling system model development, and computer code implementation.

Reflection of 50 eV to 10 keV H atoms from polycrystalline Cu, Nb and Au targets has been calculated using the binary collision cascade program MARLOWE. The fractions of particles and energy reflected (backscattered) increase with increasing atomic number of the target and decrease with increasing incident energy. The results indicate that the effects of polycrystallinity are modest, reducing the amorphous reflection coefficients by about 25 percent. The calculations agree quite well with the experimental data for Cu and Au, but are about a factor of two larger than is observed for Nb.

Progress is reported in the areas of thermal analysis of HTGR systems, axial mode spacing affects in flow distribution calculations, and performance calculations for the core auxiliary heat exchanger.

High energy reactions of halogen atoms or ions, activated by nuclear transformations, are being studied in gaseous, high pressure, and condensed phase saturated and unsaturated hydrocarbons, halomethanes, and other organic systems. Experimental and theoretical data are presented in the following areas: systematics of iodine hot atom reactions in halomethanes, reactions and systematics of iodine reactions with pentene and butene isomers, radiative neutron capture activated reactions of iodine with acetylene, gas to liquid to solid transition in hot atom chemistry, kinetic theory applications of hot atom reactions and the mathematical development of caging reactions, solvent dependence of the stereochemistry of the $sup 38$Cl for Cl substitution following $sup 37$Cl(n,$gamma$)$sup 38$Cl in liquid meso and dl-(CHFCl)$sub 2$. A technique was also developed for the radioassay of Al in urine specimens. (JSR)

Technical highlights and cost/budget data are presented for the following programs: heavy section steel technology, fission product beta and gamma energy release, LOCA release from LWR fuel, multirod burst tests, Nuclear Safety Information Center, PWR blowdown heat transfer-separate effects, Zircaloy fuel cladding collapse studies, zirconium metal-water oxidation kinetics, aerosol release and transport from LMFBR fuel, HTGR safety analysis and research, and design criteria for piping and nozzles.

A neutron counter has been evaluated for the nondestructive analysis of $sup 234$U in uranium hexafluoride. The instrument was designed by Los Alamos Scientific Laboratory for the Nuclear Safeguards Program. The method assumes that the only source of neutrons is from $sup 19$F($alpha$, n)$sup 22$Na reaction from $sup 238$U, $sup 235$U, and $sup 234$U, the yield from $sup 234$U being the most abundant. This evaluation shows that the mean of the difference between the 4 $pi$ neutron counting method and mass spectrometry is 0.0002 wt percent uranium- 234 +- 0.00015 at the 95 percent confidence level. However, the presence of $sup 232$U produces significant errors in the system. If the neutron technique is to be used for samples containing $sup 232$U in equilibrium with its daughters, the 2.61-MeV gamma peak of $sup 208$Tl must be measured and used to correct for the $sup 232$U. It has been postulated that the neutron counter might also be used to relate the $sup 234$U content of a sample to the $sup 235$U, thus estimating the $sup 235$U concentration. This evaluation notes, however, that in a variety of uranium feeds and enriched product, the $sup 234$U/$sup 235$U ratio varies too widely to enable a …

Brief discussions are given on the following topics: (1) program objectives, (2) implementation of the program, (3) program Staff as of 1 Dec. 1975, (4) subprogram reports, (5) list of major purchases, (6) list of new proposals under consideration, and (7) visitors. (auth)

A method for obtaining solutions to the time-independent Boltzmann neutron transport equation on triangular grids with nonorthogonal boundaries and anisotropic scattering is developed. A functional is obtained from the canonical form of the multigroup transport equation. The angular variable is then removed by expanding the functional in spherical harmonics, retaining only the first two moments and limiting the anisotropic scattering to be linear. The finite element method is then implemented by using quadratic Lagrange-type interpolating polynomials to span the spatial domain. The resultant set of coupled linear equations is then solved iteratively. The applicability of convergence acceleration techniques developed for the finite difference method is tested and implemented where appropriate. Finally, a number of numerical experiments are performed to evaluate the performance of the proposed method. The results are compared to results obtained by various established methods. In all cases, agreement is excellent. 16 figures, 7 tables. (auth)

This document is a review of two reports prepared in 1975 by John W. Gofman on the subject of plutonium toxicity. Because Gofman's estimates of the calculated health effects from inhaled plutonium are significantly higher than those obtained from other analyses (including the risk estimates calculated by the National Academy of Science's Advisory Committee on the Biological Effects of Ionizing Radiation), it was decided to critically review Gofman's papers and supporting arguments. This review concludes that Gofman's predictions of large numbers of plutonium-induced lung cancers from nuclear weapons testing are derived mainly from his incorrect assumptions about the effects of cigarette smoking on the retention of plutonium particulates in the tracheobronchial region of the lungs. It appears that Gofman's assumptions are considerably overstated and cannot be substantiated by currently available information. Also, Gofman's attempt to equate a given number of lung cancer deaths to a pound of plutonium tends to obfuscate rather than clarify attempts to derive risk estimates for inhaled plutonium. (auth)

This report describes the status of 2XIIB neutral beam injection experiments with stabilizing plasma. The stream suppresses ion-cyclotron fluctuations and permits density to 5 x 10$sup 13$ cm$sup -3$. The ion energy is 13 keV, and electron temperature reaches 140 eV. Plasma confinement increases with ion energy and n tau reaches 7 x 10$sup 10$ cm$sup -3$.s at 13 keV. The n tau energy scaling is consistent with electron drag and ion-ion scattering losses. Buildup on a streaming plasma in a steady-state magnetic field is described. (auth)

A new class of density fluctuations has been observed in the ATC tokamak by using spectral analysis of scattered microwaves. The observed frequency spectrum is consistent with that of drift waves with amplitudes that are maximum in the wavelength range 0.5 to 1.0 cm where finite ion Larmor radius effects are important for plasma stability. The total density fluctuation is n tilde/sub e/ greater than or equal to 5 x 10$sup -3$ anti n/sub e/. It is estimated that these fluctuations could account for a large fraction of the electron energy losses of the ATC discharge. (auth)

The work done, primarily in various aspects of U and Pu determinations, was reported in individual reports on each project. Separate abstracts were prepared. (JSR)

The physical metallurgy of Alloy 718 is updated to 1976 on the basis of a survey of post-1967 literature and current experimental data. Composition, microstructures, and mechanical properties are correlated with heat treatment parameters. The current state of understanding of phase stability, strengthening mechanisms, deformation modes, recovery, and recrystallization in this material is described.

Arrival rates of D$sup 0$, T$sup 0$, D$sup +$, T$sup +$, He$sup ++$, neutrons, and photons are given for FERF (Fusion Engineering Research Facility, a mirror confinement reactor dedicated to materials research and to component testing), a hybrid fusion-fission reactor designed primarily to produce fissile fuel, and a D-T power reactor design. For comparison a next-generation confinement-mirror experiment called MX is included. The surfaces of interest are the first wall, the end wall, the direct converter and the injector. (auth)

Resonant and non-resonant decays of short wavelength lower hybrid waves into long wave-length whistler waves and ion acoustic waves are considered. It is shown that the dominant coupling to the ion acoustic mode arises from the magnetic force producing a pressure variation along the magnetic field lines. The growth rate and the threshold condition for this decay instability compare favorably with other decay instabilities near the lower-hybrid frequency. (auth)

The unique constraints imposed on the interactions of energetic heavy ions as a result of the channeling effect are utilized to investigate the phenomenon of radiative electron capture (REC) for 17 to 40 MeV oxygen ions. Measured cross-sections and widths of the REC radiation are compared with calculations made specifically for the channeling situation.

Fusion as a power source is receiving an increasing amount of attention. Several designs have been proposed and the feasibility of each alternative is being studied. As we move closer to a working design, attention can be paid to potential biological hazards. Large magnetic fields and the emission of tritium and lithium are unique to some fusion reactor designs. The results of a review of the current state of knowledge concerning the biological effects of magnetic fields alone and in combination with ionizing radiation are summarized in this report. The purpose of the review is to help identify areas where additional biomedical research is needed for establishing guidelines for reactor design and operation. 64 references (auth)