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Responsibilities, opportunities and challenges in geophysical exploration

Description: Geophysical exploration for engineering purposes is conducted to decrease the risk in encountering site uncertainties in construction of underground facilities. Current responsibilities, opportunities and challenges for those with geophysical expertise are defined. These include: replacing the squiggly line format, developing verification sites for method evaluations, applying knowledge engineering and assuming responsibility for crucial national problems involving rock mechanics expertise.
Date: May 4, 1982
Creator: Rytle, R.J.
Partner: UNT Libraries Government Documents Department

Proton decay: 1982

Description: Employing the current world average ..lambda../sub MS/ = 0.160 GeV as input, the minimal Georgi-Glashow SU(5) model predicts sin/sup 2/theta/sub W/(m/sub W/) = 0.214, m/sub b//m/sub tau/ approx. = 2.8 and tau/sub p/ approx. = (0.4 approx. 12) x 10/sup 29/ yr. The first two predictions are in excellent agreement with experiment; but the implied proton lifetime is already somewhat below the present experimental bound. In this status report, uncertainties in tau/sub p/ are described and effects of appendages to the SU(5) model (such as new fermion generations, scalars, supersymmetry, etc.) are examined.
Date: March 4, 1982
Creator: Marciano, W.J.
Partner: UNT Libraries Government Documents Department

Heavy-ion inertial fusion: influence of target gain on accelerator parameters for vacuum-propagation regimes in reaction chambers

Description: Target physics imposes requirements on the design of inertial fusion drivers. The influence of beam propagation in near vacuum fusion reaction chambers is evaluated for the relation between target gain and the phase-space requirements of heavy-ion accelerators. Initial results suggest that neutralization of the ion beam has a much greater positive effect than the deleterious one of beam stripping provided that the fusion chamber pressure is < 10/sup -3/ torr (of Li vapor or equivalent).
Date: March 4, 1982
Creator: Mark, J.W.K.; Bangerter, R.O.; Barletta, W.A.; Fawley, W.M. & Judd, D.L.
Partner: UNT Libraries Government Documents Department

Radioactive ions beams for studying astrophysical nuclear reactions

Description: Beams of radioactive ions can be produced as secondary beams following the interaction of conventional accelerator beams with suitable targets. For example we have used beams of /sup 7/Li and /sup 12/C from an EN Tandem Van de Graaff accelerator to produce beams of /sup 7/Be and /sup 13/N via the (p,n) and (d,n) reactions respectively. These beams are focused by a system of magnetic quadrupole lenses to a secondary target. Reactions of such nuclides, especially proton capture and (p,..cap alpha..) reactions, are of interest in solar physics and in the CNO multi-cycle in massive stars. Progress toward the measurement of these reactions is discussed.
Date: November 4, 1982
Creator: Haight, R.C.; Mathews, G.J.; White, R.M.; Aviles, L.A. & Woodard, S.E.
Partner: UNT Libraries Government Documents Department

Some proposed disk heating, focusing, and beam-transport experiments for heavy-ion inertial-fusion test facilities

Description: Calculations suggest that experiments relating to disk heating, as well as beam deposition, focusing and transport can be performed within the context of current design proposals for accelerator test-facilities. Since the test-facilities have lower ion kinetic energy and beam pulse power as compared to reactor drivers, we achieve high-beam intensities at the focal spot by using short focal distance and properly designed beam optics. In this regard, the low beam emittance of suggested multi-beam designs are very useful. Possibly even higher focal spot brightness could be obtained by plasma lenses which involve external fields on the beam which is stripped to a higher charge state by passing through a plasma cell. Preliminary results suggest that intensities approx. 10/sup 13/ - 10/sup 14/ W/cm/sup 2/ are achievable. Given these intensities, deposition experiments with heating of disks to greater than a million degrees Kelvin (100 eV) are expected.
Date: March 4, 1982
Creator: Mark, J.W.K.; Bangerter, R.O.; Fawley, W.M.; Yu, S. & Judd, D.L.
Partner: UNT Libraries Government Documents Department