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Search for narrow states produced in the reaction. pi. /sup -/p. -->. n +. gamma. 's at 13 GeV/c

Description: A double arm lead-glass lead-scintillator calorimeter system was used to search for narrow states, such as the eta/sub c/, produced in the exclusive reactions ..pi../sup -/p ..-->.. ..gamma gamma..n, ..pi../sup -/p ..-->.. ..pi../sup 0/..gamma..n, and ..pi../sup -/p ..-->.. ..pi../sup 0/..pi../sup 0/n at 13 GeV/c. A 90% c.l. upper limit sigma.BR < 260 pb was found for ..gamma gamma.. states with masses from 2.6 to 3.1 GeV/c/sup 2/. Corresponding limits on narrow ..pi../sup 0/..gamma… more
Date: July 7, 1980
Creator: Chiang, I. H.; Johnson, R. A. & Kwan, B.
Partner: UNT Libraries Government Documents Department
open access

Spatial averaging algorithms for ultrasonic inspection of austenitic stainless steel welds

Description: Interpretation of ultrasonic inspection data from stainless steel welds is difficult because the signal-to-noise ratio is very low. The three main reasons for this are the granular structure of the weld, the high attenuation of stainless steel, and electronic noise. Averaging in time at the same position in space reduces electronic noise, but does not reduce ultrasonic noise from grain boundary scattering. Averaging wave-forms from different spatial positions helps reduce grain noise, but desir… more
Date: April 7, 1980
Creator: Horn, J. E.; Cooper, C.S. & Michaels, T.E.
Partner: UNT Libraries Government Documents Department
open access

Materials at extreme conditions: ICF targets

Description: Currently two simple theories are heavily used in laser-fusion research: the Thomas-Fermi-Dirac statistical model, and an atomic ionization model based on screened hydrogen like energy levels. Recent improvements in these theories are summarized. We show representation calculations of thermodynamic properties, ionization, x-ray emission rates and fast-ion stopping powers, and give a brief sketch of the major unresolved scientific questions.
Date: April 7, 1980
Creator: More, R.M.
Partner: UNT Libraries Government Documents Department
open access

Effects of end cell ion cyclotron fluctuations on central-cell ion confinement in the tandem mirror experiment (TMX)

Description: The tandem mirror device (TMX) exhibits gross stability to both MHD and microinstability modes. The end-cell plasmas provide the tandem with average minimum-B stability, while the efflux of plasma from the central cell maintains the end cells (plugs) at marginal stability to loss cone modes. For some operating conditions, a residual level of plug ion cyclotron fluctuations is detected. These oscillations dominate the fluctuation frequency spectra in both the plugs and the central cell. The pres… more
Date: April 7, 1980
Creator: Grubb, D. P.; Casper, T. A. & Clauser, J. F.
Partner: UNT Libraries Government Documents Department
open access

Design of laser-generated shockwave experiments. An approach using analytic models

Description: Two of the target-physics phenomena which must be understood before a clean experiment can be confidently performed are preheating due to suprathermal electrons and shock decay due to a shock-rarefaction interaction. Simple analytic models are described for these two processes and the predictions of these models are compared with those of the LASNEX fluid physics code. We have approached this work not with the view of surpassing or even approaching the reliability of the code calculations, but … more
Date: November 7, 1980
Creator: Lee, Y. T. & Trainor, R. J.
Partner: UNT Libraries Government Documents Department
open access

Geothermal reservoir well stimulation symposium

Description: Ten papers are included. One was abstracted previuosly. Separate abstracts were prepared for nine. (MHR)
Date: February 7, 1980
Creator: Crichlow, H.B. (ed.)
Partner: UNT Libraries Government Documents Department
open access

Energy flow in high speed perforation and cutting

Description: It is demonstrated that effects of long rod penetrators on targets can be modeled by introducing a high pressure (energy) column on the penetration path in place of the projectile. This energy can be obtained from the kinetic energy of the penetrator; the equations of state of the materials used and a Bernoulli penetration condition. The model is supported by detailed hydro calculations.
Date: October 7, 1980
Creator: van Thiel, M.
Partner: UNT Libraries Government Documents Department
open access

Technology of direct conversion for mirror reactor end-loss plasma

Description: Design concepts are presented for plasma direct convertors (PDC) intended primarily for use on the end-loss plasma from tandem-mirror reactors. Recent experimental results confirm most of these design concepts. Both a one-stage and a two-stage PDC were tested in reactor-like conditions using a 100-kV, 6-kW ion beam. In a separate test on the end of the TMX machine, a single stage PDC recovered 79 W for a net efficiency of 50%. Tandem mirror devices are well suited to PDC. The high minimum energ… more
Date: October 7, 1980
Creator: Barr, W.L. & Moir, R.W.
Partner: UNT Libraries Government Documents Department
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