NASA Scientific and Technical Aerospace Reports

20040111180 Lawrence Livermore National Lab., Livermore, CA
Beam Diagnostics Systems for the National Ignition Facility
Demaret, R. D.; Boyd, R. D.; Bliss, E. S.; Gates, A. J.; Severyn, J. R.; 2004; In English
Report No.(s): DE2003-15005543; No Copyright; Avail: National Technical Information Service (NTIS)
The National Ignition Facility (NIF) laser focuses 1.8 megajoules of ultraviolet light (wavelength 351 nanometers) from
192 beams into a 600-micrometer-diameter volume. Effective use of this output in target experiments requires that the power
output from all of the beams match within 8% over their entire 20-nanosecond waveform. The scope of NIF beam diagnostics
systems necessary to accomplish this task is unprecedented for laser facilities. Each beamline contains 110 major optical
components distributed over a 510-meter path, and diagnostic tolerances for beam measurement are demanding. Total laser
pulse energy is measured with 2.8% precision, and the interbeam temporal variation of pulse power is measured with 4%
precision. These measurement goals are achieved through use of approximately 160 sensor packages that measure the energy
at five locations and power at three locations along each beamline using 335 photodiodes, 215 calorimeters, and 36 digitizers.
Successful operation of such a system requires a high level of automation of the widely distributed sensors. Computer control
systems provide the basis for operating the shot diagnostics with repeatable accuracy, assisted by operators who oversee
system activities and setup, respond to performance exceptions, and complete calibration and maintenance tasks.
NTIS
Laser Outputs; Beams (Radiation); Waveforms; Pulsed Lasers; Numerical Control
20040111182 Stanford Linear Accelerator Center, CA, USA
Measurement of the Beta (sup O) -\g Kappa (sup * suup)(1430)(sup o)Gamma and Beta(sup +) -\gKappa(sup * sub
m)(1430)(sup O) gamma Fractions
2003; In English
Report No.(s): DE2003-815251; SLAC-PUB-10104; No Copyright; Avail: National Technical Information Service (NTIS)
No abstract available
Ionizing Radiation; Emission Spectra
20040111278 Princeton Univ., NJ
Paul Trap Simulator Experiment to Model Intense Beam Propagation in Alternating-Gradient Transport Systems
Gilson, E. P.; Davidson, R. C.; Efthimion, P. C.; Majeski, R.; Jan. 2004; 12 pp.; In English
Report No.(s): DE2004-821520; PPPL-3920; No Copyright; Avail: Department of Energy Information Bridge
Intense beam propagation is an active area of research and is at the center of various scientific studies, including heavy
ion fusion, spallation neutron sources, high energy physics, nonlinear dynamics, and nuclear waste transmutation. The results
presented here demonstrate that the Paul Trap Simulator Experiment (PTSX) is capable of simulating, in a compact cylindrical
Paul trap, beams with intensities up to 80% of the space-charge limit and that propagate for equivalent distances of over 10
km. This allows the study of research topics such as: the conditions for quiescent beam propagation, collective mode
excitation, generation and dynamics of halo particles, and distribution function effects. At the high beam intensities envisioned
in present and next-generation facilities, a fundamental understanding of the influence of collective processes and self-field
effects on beam transport and stability properties must be developed.
NTIS
Propagation Modes; Radioactive Wastes; Transport Properties
20040111305 NASA Langley Research Center, Hampton, VA, USA
NASA Noise Reduction Program for Advanced Subsonic Transports
Stephens, David G.; Cazier, F. W., Jr.; [1995]; 6 pp.; In English; No Copyright; Avail: CASI; A02, Hardcopy
Aircraft noise is an important byproduct of the world’s air transportation system. Because of growing public interest and
sensitivity to noise, noise reduction technology is becoming increasingly important to the unconstrained growth and utilization
of the air transportation system. Unless noise technology keeps pace with public demands, noise restrictions at the
international, national and/or local levels may unduly constrain the growth and capacity of the system to serve the public. In
recognition of the importance of noise technology to the future of air transportation as well as the viability and competitiveness
of the aircraft that operate within the system, NASA, the FAA and the industry have developed noise reduction technology
programs having application to virtually all classes of subsonic and supersonic aircraft envisioned to operate far into the 21st
century. The purpose of this paper is to describe the scope and focus of the Advanced Subsonic Technology Noise Reduction
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