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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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The interpretation of miniclusters containing hadrons as well as gamma-quanta by the cascade decays of heavy mesons, in the first turn, of charmed D'-mesons is discussed.
Nuclear charge distribution model for muon-meson atomic calculations
Design and performance of large liquid helium scintillation counter for meson experiments
The decay rates of leading edge Regge trajectory states are calculated for very high level number in open bosonic string theories, ignoring tachyon final states. The optical theorem simplifies the analysis while enabling identification of the different mass level decay channels. The main result is that (in four dimensions) the greatest single channel is the emission of a single photon and a state of the next mass level down. A simple asymptotic formula for arbitrarily high level number is given for this process. Also calculated is the total decay rate exactly up to N=100. It shows little variation over this range but appears to decrease for larger N. The formalism is checked in examples and the decay rate of the first excited level calculated for open superstring theories. The calculation may also have implications for high spin meson resonances.
A three-dimensional study of atmospheric gamma rays with energy greater than 30 MeV has been carried out. A knowledge of these atmospheric secondaries has significant applications to the study of cosmic gamma rays. For detectors carried on balloons, atmospherically produced gamma rays are the major source of background. For satellite detectors, atmospheric secondaries provide a calibration source. Experimental results were obtained from four balloon flights from Palestine, Texas, with a 15 cm by 15 cm digitized wire grid spark chamber. The energy spectrum for downward-moving gamma rays steepens with increasing atmospheric depth. Near the top of the atmosphere, the spectrum steepens with increasing zenith angle. A new model of atmospheric secondary production has calculated the depth, the energy, and the zenith angle dependence of gamma rays above 30 MeV, using a comprehensive three-dimensional Monte Carlo model of the nucleon-meson-electromagnetic cascade.
Dynamics and symmetries of nonleptonic hyperon decay based on assumptions of parity-violating and parity-conserving amplitudes, inverse associated production amplitudes and SU SYMMETRY
Algebra of factorized Regge pole residues applied to obtain relations between meson-baryon and baryon-baryon exchange processes
Polarization measurements in pion-proton elastic scattering mechanics
Pion-nucleon phase shift analysis using pion- nucleon and pion-pion resonance parameters
Impulse approximation for pion absorption on light nuclei with emission of fast nucleons
Distorted wave one-meson-exchange /DWOME/ for high-energy elementary particle reaction analysis, leading to different expression for transition amplitude
The Small Astronomy Satellite (SAS)-2, launched on November 15, 1972, carried into orbit a 32-deck magnetic-core digitized spark chamber gamma ray telescope to study celestial gamma radiation in the energy range above 30 MeV. In the study of several regions with b sub 2 15 deg, a finite, diffuse flux of gamma rays with a steep energy spectrum in the energy region from 35 to 200 MeV is observed. Representing the energy spectrum by a power law of the form dJ/dE = AE to - alpha power over this energy range, alpha is found along with the integral flux above 100 MeV. Combining this result with existing low energy gamma ray data yields an energy spectrum which is not a simple power law in energy, as in the X-ray region, but which demonstrates first an increase and then a decrease in slope, consistent within uncertainties with that predicted by cosmological theories, including the continuous production of high energy gamma rays primarily from neutral pi mesons throughout the history of the universe.
Muon-meson X-ray spectral analysis of deformed isotopic tungsten, uranium, and samarium nuclei
Phase shift analysis of pi-helium elastic scattering using helium bubble chamber
The energy spectrum of cascade showers induced by electromagnetic interactions of high energy muons of horizontal cosmic ray flux in iron absorber was measured. The total observation time exceeded 22,000 hours. Both the energy spectrum and angular distributions of cascade showers are fairly described in terms of the usual muon generation processes, with a single power index of the parent meson spectrum over the muon energy range from 150 GeV to 5 TeV.
Normal scalar nonet, K1 meson-2 pion decay, K1-K2 mass difference and S-wave pi-pion scattering
Muon energy spectrum at sea level determined from large ionization burst spectrum