86 Matching Results

Search Results

Results: 1 - 24 next
open access

Hadron-hadron physics at high energy and luminosity

Description: I review some recent theoretical issues relevant to the physics of hadron-hadron collisions. I discuss processes where either energy or luminosity is the most important feature and emphasize the need for experiments at luminosities of 10{sup 33}cm{sup -2}sec{sup 1} if the full range of physics options is to be thoroughly explored. 22 refs., 10 figs.
Date: November 8, 1989
Creator: Hinchliffe, I.
Partner: UNT Libraries Government Documents Department
open access

Geometric continuum regularization of quantum field theory

Description: An overview of the continuum regularization program is given. The program is traced from its roots in stochastic quantization, with emphasis on the examples of regularized gauge theory, the regularized general nonlinear sigma model and regularized quantum gravity. In its coordinate-invariant form, the regularization is seen as entirely geometric: only the supermetric on field deformations is regularized, and the prescription provides universal nonperturbative invariant continuum regularization … more
Date: November 8, 1989
Creator: Halpern, M.B. (California Univ., Berkeley, CA (USA). Dept. of Physics)
Partner: UNT Libraries Government Documents Department
open access

Imaging system for obtaining space- and time-resolved plasma images on TMX

Description: A Reticon 50 x 50 photodiode array camera has been placed on Livermore's Tandem Mirror Experiment to view a 56-cm diameter plasma source of visible, vacuum-ultraviolet, and x-ray photons. The compact camera views the source through a pinhole, filters, a fiber optic coupler, a microchannel plate intensifier (MCPI), and a reducer. The images are digitized (at 3.3 MHz) and stored in a large, high-speed memory that has a capacity of 45 images. A local LSI-11 microprocessor provides immediate proces… more
Date: April 8, 1980
Creator: Koehler, H.A. & Frerking, C.E.
Partner: UNT Libraries Government Documents Department
open access

Study of optical model parameters for high energy neutron cross sections from 5 to 50 MeV in the mass-140 region

Description: A study of the neutron optical potential on nuclei near mass-140 was begun to extend the energy range and improve the precision of previous neutron total cross section measurements. The extended energy range of this measurement reveals maxima and minima in the total cross section that are evidence of the nuclear Ramsauer effect. A 100-MeV linear accelerator is used to produce a continuum of neutron energies from a Ta-Be conversion target. A 250-meter flight path is used to measure neutron energ… more
Date: May 8, 1980
Creator: Phillips, T.W.; Camarda, H.S. & White, R.M.
Partner: UNT Libraries Government Documents Department
open access

Backgrounds to the detection of two-body hadronic B decays

Description: We consider backgrounds to the detection of the two-body hadronic decay modes of neutral B mesons and baryons. The largest background is due to the correlated production of pairs of high-p/sub T/ hadrons in the target, but this can be adequately rejected provided the experimental apparatus has sufficient resolution in mass and decay vertex. Another possible source of background arises from the production and decay of charmed and strange particles. Since these particles can travel considerable d… more
Date: January 8, 1988
Creator: Kaplan, D. M.; Peng, Jen-Chieh; Abrams, G. S. & Stockdale, I. E.
Partner: UNT Libraries Government Documents Department
open access

Present capabilities and new developments in antenna modeling with the numerical electromagnetics code NEC

Description: Computer modeling of antennas, since its start in the late 1960's, has become a powerful and widely used tool for antenna design. Computer codes have been developed based on the Method-of-Moments, Geometrical Theory of Diffraction, or integration of Maxwell's equations. Of such tools, the Numerical Electromagnetics Code-Method of Moments (NEC) has become one of the most widely used codes for modeling resonant sized antennas. There are several reasons for this including the systematic updating a… more
Date: April 8, 1988
Creator: Burke, G. J.
Partner: UNT Libraries Government Documents Department
open access

Calibration of a neutron log in partially saturated media IV: effects of sonde-wall gap

Description: A gap between a neutron sonde and the wall of a borehole can have a significant effect on the observed count rate. This effect was determined experimentally to be linear with gaps as large as 2.5 cm. The count rate is given by N/sub N/ = K/sub 0/ + K/sub 1/g where K/sub 0/ is the count rate that would be observed at zero gap, and g is the gap. The parameters K/sub 0/ and K/sub 1/ are dependent on both water (ie. hydrogen) content and bulk density. In many situations failure to correct the count… more
Date: March 8, 1984
Creator: Axelrod, M. C. & Hearst, J. R.
Partner: UNT Libraries Government Documents Department
open access

Experimental study of flame propagation in semiconfined geometries with obstacles

Description: Accidents in which large quantities of liquefied natural gas (LNG) or other combustible materials are spilled can potentially lead to disastrous consequences, especially if the dispersing combustible cloud finds a suitable ignition source. So far, very little is known about the detailed behavior of a large burning cloud. Full-scale experiments are economically prohibitive, and therefore one must rely on laboratory and field experiments of smaller size, scaling up the results to make predictions… more
Date: February 8, 1982
Creator: Urtiew, P.A.; Brandeis, J. & Hogan, W.J.
Partner: UNT Libraries Government Documents Department
open access

Construction techniques for short iron-free dipole magnets

Description: A method was developed for economically fabricating short, wire-wound, steering magnets with maximum length, cosine-distributed, axial elements. This method utilizes multifunctional tooling to precisely flat-wind two-layer dipole halves that are subsequently reformed and encapsulated into semicylindrical form with confinement of the end turns into thin, half discs normal to the magnet axis. This paper addresses the magnet fabrication in detail, highlighting the inherent quality control features… more
Date: November 8, 1983
Creator: Harvey, A.R.
Partner: UNT Libraries Government Documents Department
open access

Mirror Advanced Reactor Study (MARS) final report summary

Description: The Mirror Advanced Reactor Study (MARS) has resulted in an overview of a first-generation tandem mirror reactor. The central cell fusion plasma is self-sustained by alpha heating (ignition), while electron-cyclotron resonance heating and negative ion beams maintain the electrostatic confining potentials in the end plugs. Plug injection power is reduced by the use of high-field choke coils and thermal barriers, concepts to be tested in the Tandem Mirror Experiment-Upgrade (TMX-U) and Mirror Fus… more
Date: December 8, 1983
Creator: Henning, C. D.; Logan, B. G.; Carlson, G. A.; Perkins, L. J.; Werner, R. W.; Gordon, J. D. et al.
Partner: UNT Libraries Government Documents Department
open access

Electromagnetic velocity gauge: use of multiple gauges, time response, and flow perturbations

Description: We have developed an in-situ electromagnetic velocity (EMV) gauge system for use in multiple-gauge studies of initiating and detonating explosives. We have also investigated the risetime of the gauge and the manner in which it perturbs a reactive flow. We report on the special precautions that are necessary in multiple gauge experiments to reduce lead spreading, simplify target fabrication problems and minimize cross talk through the conducting explosive. Agreement between measured stress recor… more
Date: April 8, 1981
Creator: Erickson, L. M.; Johnson, C. B.; Parker, N. L.; Vantine, H. C.; Weingart, R. C. & Lee, R. S.
Partner: UNT Libraries Government Documents Department
open access

Multivariable current control for electrically and magnetically coupled superconducting magnets. Revision 1

Description: Superconducting magnet systems under construction and projected for the future contain magnets that are magnetically coupled and electrically connected with shared power supplies. A change in one power supply voltage affects all of the magnet currents. A current controller for these system must be designed as a multivariable system. The power describes a method, based on decoupling control, for the rational design of these systems. Dynamic decoupling is achieved by cross-feedback of the measure… more
Date: February 8, 1985
Creator: Owen, E. W. & Shimer, D. W.
Partner: UNT Libraries Government Documents Department
open access

Conversion-electron experiment to characterize the decay of the /sup 237/Np shape isomer

Description: Conversion electrons from the decay of low-lying levels of /sup 237/Np have been measured to detect the population of these levels by gamma-ray decay of the /sup 237/Np shape isomer. Analysis of the 208-keV transition L conversion-electron peak gives an upper limit of about 17 ..mu..b for the population of the 3/2/sup -/ 267-keV level in /sup 237/Np from the shape isomer decay. Model calculations are compared with the measured limit. Improvements are suggested for this experiment. 9 refs., 4 fi… more
Date: December 8, 1987
Creator: Henry, E. A.; Becker, J. A.; Bauer, R. W.; Gardner, D. G.; Decman, D. J.; Meyer, R. A. et al.
Partner: UNT Libraries Government Documents Department
open access

Monitoring the chemistry and materials of the Magma Geothermal Binary Cycle Generating Plant

Description: The Magma Binary Cycle Plant at the East Mesa KGRA is the first geothermal generating plant of its kind in the US. In cooperation with the Magma Electric Company, the Pacific Northwest Laboratory conducted a DOE sponsored program at the plant to document the chemistry and materials performance during the first two years of operation. This paper describes the methods used, the instruments and the results.
Date: October 8, 1982
Creator: Shannon, Donald W.
Partner: UNT Libraries Government Documents Department
open access

The replacement of an electromagnetic primary sodium sampling pump in the Fast Flux Test Facility

Description: On November 16, 1984 a leak was discovered in one of the Fast Flux Test Facility (FFTF) Primary Sodium Sampling System electromagnetic pumps. The leak was discovered in the course of routine cell entry to investigate a shorted trace heat element. The purpose of this paper is to describe the circumstances surrounding the occurrence of the leak, the actions taken to replace the damaged pump and the additional steps which were necessary to return the plant to power. In addition, the processes invo… more
Date: November 8, 1985
Creator: Grygiel, M. L. & McCargar, C. G.
Partner: UNT Libraries Government Documents Department
open access

Automatic gas-levitation system for vacuum deposition of laser-fusion targets

Description: An improved simple system has been developed to gas-levitate microspheres during vacuum-deposition processes. The automatic operation relies on two effects: a lateral stabilizing force provided by a centering-ring; and an automatically incremented gas metering system to offset weight increases during coating.
Date: September 8, 1981
Creator: Jordan, C. W.; Cameron, G. R.; Krenik, R. M. & Crane, J. K.
Partner: UNT Libraries Government Documents Department
open access

Low-level-signal data acquisition for the MFTF superconducting-magnet system

Description: Acquisition of low level signals from sensors mounted on the superconducting yin-yang magnet in the Mirror Fusion Test Facility (MFTF) imposes very strict requirements on the magnet signal conditioning and data acquisition system. Of the various types of sensors required, thermocouples, strain gages, and voltage taps produce very low level outputs. These low level outputs must be accurately measured in the harsh environment of slowly varying magnetic fields, cryogenic temperatures, high vacuum,… more
Date: October 8, 1981
Creator: Montoya, C.R.
Partner: UNT Libraries Government Documents Department
open access

Electroweak symmetry breaking studies at the pp colliders of the 1990's and beyond

Description: Within the conventional framework of a spontaneously broken gauge theory, general principles establish that the electroweak symmetry is broken by a new force that may be weak with associated new quanta below 1 TeV or strong with quanta above 1 TeV. The SSC parameters, ..sqrt..s = 40 TeV and L = 10/sup 33/ cm/sup /minus/2/s/sup /minus/1/, define a minimal facility with assured capability to observe the signals of symmetry breaking by a strong force above 1 TeV. Foreseeable luminosity upgrades wo… more
Date: March 8, 1989
Creator: Chanowitz, Michael S.
Partner: UNT Libraries Government Documents Department
open access

Multivariable current control for electrically and magnetically coupled superconducting magnets

Description: Superconducting magnet systems under construction and projected for the future contain magnets that are magnetically coupled and electrically connected with shared power supplies. A change in one power supply voltage affects all of the magnet currents. A current controller for these systems must be designed as a multivariable system. The paper describes a method, based on decoupling control, for the rational design of these systems. Dynamic decoupling is achieved by cross-feedback of the measur… more
Date: February 8, 1985
Creator: Owen, E. W. & Shimer, D. W.
Partner: UNT Libraries Government Documents Department
open access

Novel neutralized-beam intense neutron source for fusion technology development

Description: We describe a neutralized-beam intense neutron source (NBINS) as a relevant application of fusion technology for the type of high-current ion sources and neutral beamlines now being developed for heating and fueling of magnetic-fusion-energy confinement systems. This near-term application would support parallel development of highly reliable steady-state higher-voltage neutral D/sup 0/ and T/sup 0/ beams and provide a relatively inexpensive source of fusion neutrons for materials testing at up … more
Date: July 8, 1983
Creator: Osher, J.E. & Perkins, L.J.
Partner: UNT Libraries Government Documents Department
open access

The characterization of Nb/sub 3/Sn superconductors for use in magnets of 19 T and greater

Description: Increased resolution of NMR spectrometry will require the use of very high field Nb/sub 3/Sn superconducting magnets. Here we report the results of our investigation into mechanical and temperature effects on internal-Sn superconductors similar to those proposed for use in a 900 MHz, 21 T NMR magnet system. Thermal precompression was found to be about 0.225%, and the irreversible strain was about 0.8%. Fatigue degradation was not observed at cyclic intrinsic strains below 0.575%. Additions of r… more
Date: August 8, 1989
Creator: Summers, L. T.; Strum, M. J. & Miller, J. R.
Partner: UNT Libraries Government Documents Department
open access

Energy balance in laser-irradiated vaporizing droplets

Description: We analyze the interactions of atmospheric aerosols with a high-energy laser beam. The energy balance equation allows us to compute the conversion of the pulse energy into temperature increase, vaporization, conduction, and convection. We also include the shrinkage term whose significance has recently been discussed by Davies and Brock.
Date: September 8, 1987
Creator: Zardecki, A. & Armstrong, R.L.
Partner: UNT Libraries Government Documents Department
open access

Observation of excited H/sup 0/ atoms produced by relativistic H/sup /minus// ions in carbon and formvar foils

Description: We have measured the relative yield of several low-lying excited states of neutral hydrogen atoms produced by the passage of 226-MeV and 581-MeV H/sup /minus// ions through thin carbon foils and a tilted formvar foil. The relative yields of H/sup /minus///sub /asterisk//(n = 2,3, 4) were measured for 17 different carbon foils ranging in thickness from 662 /angstrom/ to 5386 /angstrom/ at 581 MeV. The relative yield of H/sup 0//sup /asterisk//(n = 2) was also measured for these carbon foils at 2… more
Date: February 8, 1989
Creator: Mohagheghi, A. H.; Bryant, H. C.; Harris, P. G.; Tang, C. Y.; Quick, C. R.; Reeder, R. A. et al.
Partner: UNT Libraries Government Documents Department
open access

The International Thermonuclear Experimental Reactor (ITER): Design and materials selection

Description: The success of ITER relies on aggressive design of the superconducting magnet systems. This design emphasized high radiation-damage tolerance, acceptance of high nuclear heat loads, and high operational stresses in the Toroidal Field (TF) magnets. The design of the Central Solenoid (CS) magnets, although they will be well shielded from the plasma, is equally aggressive due to the need for very high magnetic fields (14 T) and long term operation at high cyclic stresses. Success of these magnet d… more
Date: August 8, 1989
Creator: Summers, L. T.; Miller, J. R. & Heim, J. R.
Partner: UNT Libraries Government Documents Department
Back to Top of Screen