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The total cross sections of the reactions DDp, DDn, TD at 10 kev to 10 Mev are estimated from a review of the experimental data up to January 1951. Maxwell averages for DDp and TD computed from these estimates are given, together with some fitted analytic expressions provided for machine use. A collection of the identifiable earlier estimates is also included for reference and for comparison with the new figures. For relative order of magnitude purposes, cross sections and the derived Maxwell averages are given down to 50 ev using the theoretical Gamow slopes for the extrapolation. Gamow plots for the derived cross sections above l0 kev arc also given. Much of the primary experimental data exists in the form of thick target yields and we find the most uncertain factor in converting these thick targets yields into cross sections is the magnitude of the D/sub 2/O stopping cross section. The particular D/sub 2/O stopping cross section relation used in this derivation together with some of the earlier stopping cross sections are given. Thick target yields are included for both DD and TD on D/sub 2/ targets, at 0.01 to 1 Mev, experimental values being supplemented by calculated values.

Quarterly technical report including reports on chemistry of source, fissionable, and structural elements, nuclear chemistry, radio-organic chemistry, chemistry of separations processes, chemical physics, radiation chemistry, and instrumentation. [From Abstract]

Report presenting an investigation to determine some effects of tail damping and wing-tail interference on the rolling effectiveness of ailerons and a spoiler on a modified-delta wing. Results regarding the effect of adding fixed tail surfaces, effect of moving the horizontal tail out of the plane of the wing, and a comparison with theory are provided.

Report describing the design and flight evaluation of an air-borne target simulator using precomputed relative kinematics for use in tracking studies of fighter aircraft equipped with scope-presentation type fire-control systems. Testing occurred in an F86D airplane equipped with a Hughes E-4 fire-control system. Results regarding relative kinematic programming considerations and restrictions to system evaluation are provided.

Report presenting free-flight tests of two rocket models at a range of Mach numbers to determine the control rolling effectiveness and system operation of an autorotating-vane spoiler on a missile configuration with an 80 degree delta, cruciform wing. Results indicated that the system operated fairly satisfactorily as a flicker-type roll control except at low supersonic speeds.

"An investigation has been conducted in the Langley Unitary Plan Wind tunnel to determine the static stability and drag characteristics of a 1/10-scale model of the AVCO booster vehicle. The tests were made at a constant Reynolds number, based on maximum nose diameter, of 1.09 x 10(exp 6)6 at Mach numbers of 1.60 and 2.00" (p. 1).

Fourier analyses are made on two functions. The first is a step function forward from periodic samples of a sinusoid. If the frequency of the sinusoid is less than one-half of the sampling frequency, it is shown that the step function has no frequency components less than one-half of the sampling frequency other than that of phase, and duration with respect to the interval of the analysis. It is shown that the insertion of a blank space in the period of analysis reduces greatly the uncertainty of the amplitude of the initial sinusoid as estimated from the results of the Fourier analysis. The results of the analyses are useful in the design and evaluation of certain analog data-analyzing systems.