Description and capabilities of a traveling wave sonic boom simulator

Description and capabilities of traveling wave sonic boom simulator

Research and development of a sonic boom simulation device

Design and performance of sonic boom simulato

The Electric Quadrupole Moment of In^(115)

Measurements of the lines λ7852 (5s6p^1P→5s6s^1S) are λ8241 (5s6p^1P→5s5d^1D) of In II show deviations from interval rule. These deviations are satisfactorily accounted for by the presence of a nuclear electric quadrupole moment which from the first of the lines is found to be Q=0.82×10^(−24) cm^2. No trace of lines due to In^(113) was found

Evidence for a Nuclear Electric Quadrupole Moment for Sb^(123)

Measurements of the hyperfine structure of the line λ5895 of Sb II by the use of a Fabry-Perot interferometer have shown that there are deviations from the interval rule in the case of the isotope with mass number 123. The hyperfine structure intervals of the ^3D_1 level of Sb^(121) (I=5/2) are found to be 0.6801 and 0.4832 cm^(−1). The corresponding intervals in Sb^(123) (I=7/2) are 0.4814 and 0.3603 cm^(−1). The error in these measurements is of the order of 0.001 cm. The observed ratio of the two separations gives 1.407 and 1.336 for the light and heavy isotope, respectively, whereas the corresponding ratios on the basis of the interval rule are 1.400 and 1.286. The deviation in the case of the light isotope is within the experimental error. The deviation for the heavy isotope, however, is a real effect which cannot be accounted for on the basis of perturbing effects of neighboring levels and must therefore be ascribed to the presence of an electric quadrupole moment of the nucleus of Sb^(123)

Lightweight Damage Tolerant High-Temperature Radiators for Space Propulsion

No abstract availabl

Lightweight, High-Temperature Radiator for Space Propulsion

For high-power nuclear-electric spacecraft, the radiator can account for 40% or more of the power system mass and a large fraction of the total vehicle mass. Improvements in the heat rejection per unit mass rely on lower-density and higher-thermal conductivity materials. Current radiators achieve near-ideal surface radiation through high-emissivity coatings, so improvements in heat rejection per unit area can be accomplished only by raising the temperature at which heat is rejected. We have been investigating materials that have the potential to deliver significant reductions in mass density and significant improvements in thermal conductivity, while expanding the feasible range of temperature for heat rejection up to 1000 K and higher. The presentation will discuss the experimental results and models of the heat transfer in matrix-free carbon fiber fins. Thermal testing of other carbon-based fin materials including carbon nanotube cloth and a carbon nanotube composite will also be presented