When light propagates with the wave normal in the direction of an optic axis of a biaxial crystal, the usual ray theory breaks down. This phenomenon can be analyzed by means of an asymptotic solution of Maxwell's equations. The intensity is governed by a partial differential equation within the phase surfaces, instead of ordinary differential equations along rays. This example slows that light does not always propagate along rays. A similar phenomenon occurs in hydromagnetics.

Abstract. A fast-slow coincidence scintillation spectrometer for gamma-gamma cascade measurements following thermal neutron absorption in nuclei is now in operation at the Livermore 1-megawatt pool-type reactor. Design features of the spectrometer and experimental techniques in its use are discussed with particular emphasis on the application of the recently introduced sum-coincidence method for analysis of capture-gamma double cascades. A new technique for the determination of added neutron binding energy is presented and various types of coincidence data from appropriate experiments are illustrated.

A series of critical experiments with blocks of 2% U235-enriched UF4-C25H52 has been initiated at the ORNL Critical Experiments Facility. Thus far assemblies with H:U235 atomic ratios of 195 and 294 have been built in parallelepipedal and simulated cylindrical geometries, both reflected and unreflected. From the results the minimum critical masses for reflected spheres have been determined to be 16.3 and 8.5 kg of U235 for fuel mixtures with H:U235 atomic ratios of 195 and 294, respectively. The minimum critical masses for unreflected spheres of these two fuel mixtures are 24.3 and 12.7 kg of U235, respectively.

This is the final report on the progress, "A Wide-Range Neutron Detector and Monitoring Instrument," ARF 1118-6. This report covers activities from May 8, 1958 to May 8, 1959. This report describes the basic design principles of a proportional counter that has been constructed whose cathode diameter increases towards one end.

Report presenting testing of gaseous hydrogen fuel burned in a connected-pipe combustor with a cross section equal to 35 degrees sector of a 28-inch diameter. Eleven shrouded fuel-injector configurations were used to obtain combustion data at specified high-altitude ramjet combustor conditions. Results regarding shroud air blockage, mixing tabs, higher equivalence-ratio burning, injector size, flameholder durability, burner length, combustion efficiency, and temperature profile are provided.

A qualitative theory for cake formation in ThO2 slurries is presented. The sphere formation which occurs in "Standard" slurry can be explained on the same basis. The irregular and unpredictable yield strength is easily fitted into the theory. On the basis of this theory, the writer has been led to the conclusion that only colloidally stable slurries, or slurries with crystallites or comminution-resistant particles which are large enough to overcome colloidal effects (probably larger than 0.1u) can be used with assurance in the ThO2 reactor system. This conclusion holds for 300 gm/kg slurries as well as for more concentrated mixtures.

In analyzing stresses, deflections, and forces in piping and certain structural systems, it is useful to have a set of equations giving the deflections at any point of a curved beam in terms of the various loads acting on the beam. This technical report presents the deflection equations for a curved circular-arc beam of variable length. The cases treated include in-plane and out-of-plane bending due to forces and moments applied to the end of the beam in three principal directions, and uniformly distributed loads applied along the beam in these three directions. Deflections were calculated by the strain energy method using Castigliano's theorem.

Report presenting testing of a transonic compressor rotor with double-circular-arc blade sections and inlet guide vanes turning counter to the direction of rotor whirl to determine the effect of blade-row interaction on the performance of a transonic rotor. Results regarding overall performance, guide-vane performance, rotor-inlet conditions, rotor-outlet conditions, consideration of radial equilibrium, blade-element performance, and axial asymmetry in rotor-outlet flow are provided.

Report presenting flight tests on an FJ-3 airplane to determine the flight characteristics of a carrier-type airplane with area-suction and blowing boundary-layer control on the trailing-edge flaps. Measurements were made of lift, drag, and bleed-air requirements for the different types of boundary-layer control systems. Results regarding lift, drag, flow requirements, performance, pilots' opinions, and approach-speed criteria are provided.

Report presenting a flight test of pentaborane fuel in an air-launched ramjet engine with a design free-stream Mach number of 1.8. The ramjet used in the investigation had a revised spray bar-flameholder configuration. Results regarding propulsive thrust and propulsive-thrust specific fuel consumption are provided.

Flight investigation of pentaborane fuel in 9.75- inch-diameter ramjet engine with downstream fuel injection.

Report issued by the Oak Ridge National Laboratory discussing quarterly progress of the Homogeneous Reactor Project. Progress of operations, design, development, and analysis is presented. This report includes tables, illustrations, and photographs.

Memorandum presenting an investigation of the static longitudinal stability characteristics of two wings of different construction and slightly different flexibilities in the 16-foot transonic tunnel. The wings had the same external dimensions but one had a steel construction and the other was made of plastic reinforced by a steel core.

Memorandum presenting a general wave equation derived governing the propagation of sound in a stratified moving medium, the velocity of which varies only along one coordinate. A simplified equation is adopted which is satisfactory for the present application.

A report discussing a geologic reconnaissance of the Capitol Reef area, undertaken to evaluate the uranium deposits and determine their geologic characteristics.

"A linear stability analysis and flight-test investigation has been performed on a rolleron-type roll-rate stabilization system for a canard-type missile configuration through a Mach number range from 0.9 to 2.3. This type damper provides roll damping by the action of gyro-actuated uncoupled wing-tip ailerons. A dynamic roll instability predicted by the analysis was confirmed by flight testing and was subsequently eliminated by the introduction of control-surface damping about the rolleron hinge line" (p. 1).

Report presenting the results of an experimental investigation of the dynamic stability and control of a simple ducted-fan model in hovering flight in order to provide basic information on the stability and control of jet vertically rising airplanes in hovering flight. The investigation primarily consisted of flight tests with the model hovering at altitude and near the ground.

Memorandum presenting a rocket-propelled model flown to determine the effects of four wing-mounted bomb-type external stores on the trim, buffet, and drag characteristics of a wing-fuselage configuration with a 45 degree sweptback wing. The model is compared with data from a similar model without stores. Results regarding trim, buffet, lift and stability, and drag are provided.

The present investigation was made at a free-stream Mach number of 1.59 to compare the afterbody drags to a series of conical boattailed models at zero angle of attack. Afterbody drags were obtained for both the power-off and the power-on conditions. Power-on drags were obtained as a function of afterbody fineness ratio, jet pressure ratio and divergence, and jet Mach number.

Report presenting the results of deflection tests on the wing of a full-scale, swept-wing jet bomber in the form of structural influence coefficients relating the deflection of a system of points on the wing and concentrated loads applied on the wing spars. The procedures for determining the coefficients are included.

The following report discusses the operation of the nuclear research reactor at the University of Michigan, as well as the maximum credible accident to the reactor.

Abstract: "A method is described for determining moisture on uranium and uranium oxides. This method should also be applicable to solid samples which, when heated, do not decompose to form water or liberate a substance which will react with Fischer's reagent. The method should be especially applicable to samples which are insoluble in alcohol or Karl Fischer reagent under normal titration conditions, or which will themselves react with the reagent. The amount of moisture on uranium and uranium oxide was found to be 0.02% except when the oxide was found to be 0.02% except when the oxide source was uranyl sulfate. In this case, the moisture content was found to be 0.1%. Modifications of the procedure and apparatus are presented for improving the accuracy and shortening the time necessary for the determination."

Memorandum presenting measurements of some of the high-speed characteristics of the D-558-1 airplane up to Mach number 0.89. The results of the tests showed that the stabilizer incidence drastically affected the longitudinal trim characteristics above a Mach number of 0.80.

Technical report includes three reports of research progress: 1) Range Measurements on 190 Mev Deuterons, M. Stephan; 2) Meson measurements, C. Lattes; and 3) N-P Scattering, R. Christian.