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Schemes for anti pp interactions at ISABELLE

Description: Various schemes for obtaining anti pp interactions are outlined, and the luminosities obtainable for each case calculated. In the simplest realistic case, a luminosity of 1.3 x 10/sup 29/ is obtained with a 13 hour filling time. The addition of special rf systems in both the AGS and ISABELLE give a scheme with luminosity 8 x 10/sup 29/ in 6 hours. The use of stochastic cooling to stack raises the luminosity to as high as 10/sup 31/ but the filling time is then 68 hours. Finally a scheme is cons… more
Date: September 8, 1977
Creator: Palmer, Robert B.
Partner: UNT Libraries Government Documents Department
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Computer program SCAP-BR for gamma-ray streaming through multi-legged ducts

Description: A computer program, SCAP-BR, has been developed at Burns and Roe for the gamma-ray streaming analysis through multi-legged ducts. SCAP-BR is a modified version of the single scattering code, SCAP, incorporating capabilities of handling multiple scattering and volumetric source geometries. It utilizes the point kernel integration method to calculate both the line-of-sight and scattered gamma dose rates by employing the ray tracing technique through complex shield geometries. The multiple scatter… more
Date: December 8, 1977
Creator: Byoun, T. Y.; Babel, P. J. & Dajani, A. T.
Partner: UNT Libraries Government Documents Department
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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
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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
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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
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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
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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
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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
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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
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Radiation-driven evolution of low-mass x-ray binaries and the formation of millisecond pulsars

Description: Recent data on low-mass X-ray binaries (LMXBs) and millisecond pulsars (MSPs) pose a challenge to evolutionary theories which neglect the effects of disk and comparison irradiation. Here we discuss the main features of a radiation-driven (RD) evolutionary model that may be applicable to several LMXBs. According to this model, radiation from the accreting compact star in LMXBs vaporizes'' the accretion disk and the companion star by driving a self-sustained mass loss until a sudden accretion-tur… more
Date: August 8, 1991
Creator: Tavani, M. (Lawrence Livermore National Lab., CA (United States) California Univ., Berkeley, CA (United States). Dept. of Astronomy)
Partner: UNT Libraries Government Documents Department
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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
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Application of telerobotic control to remote processing of nuclear material

Description: In processing radioactive material there are certain steps which have customarily required operators working at glove box enclosures. This can subject the operators to low level radiation dosages and the risk of accidental contamination, as well as generate significant radioactive waste to accommodate the human interaction. An automated system is being developed to replace the operator at the glove box and thus remove the human from these risks, and minimize waste. Although most of the processi… more
Date: July 8, 1991
Creator: Merrill, R. D.; Grasz, E. L.; Herget, C. J.; Gavel, D. T.; Addis, R. B. & DeMinico, G. A.
Partner: UNT Libraries Government Documents Department
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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
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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
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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
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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
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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
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Assessing Recharge and Geological Model Uncertainty at the Climax Mine Area of the Nevada Test Site

Description: Hydrologic analyses are commonly based on a single conceptual-mathematical model. Yet hydrologic environments are open and complex, rendering them prone to multiple interpretations and mathematical descriptions. Considering conceptual model uncertainty is a critical process in hydrologic uncertainty assessment. This study assesses recharge and geologic model uncertainty for the Climax mine area of the Nevada Test Site, Nevada. Five alternative recharge models have been independently developed f… more
Date: November 8, 2007
Creator: Ye, M.; Pohlmann, K.; Chapman, J. & Pohll, G.
Partner: UNT Libraries Government Documents Department
open access

Beyond Spin-Orbit: Probing Electron Correlation in the Pu 5f States

Description: Experiments planned to address the issue of electron correlation in the Pu 5f states are described herein. The key is the utilization of the Fano Effect, the observation of spin polarization in nonmagnetic systems, using chiral excitation such as circularly polarized X-rays.
Date: May 8, 2006
Creator: Tobin, J G
Partner: UNT Libraries Government Documents Department
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Nuclear Electric Dipole Moment of 3He

Description: A permanent electric dipole moment (EDM) of a physical system would require time-reversal (T) violation, which is equivalent to charge-conjugation-parity (CP) violation by CPT invariance. Experimental programs are currently pushing the limits on EDMs in atoms, nuclei, and the neutron to regimes of fundamental theoretical interest. Nuclear EDMs can be studied at ion storage rings with sensitivities that may be competitive with atomic and neutron measurements. Here we calculate the magnitude of t… more
Date: April 8, 2008
Creator: Stetcu, I; P.Liu, C; Friar, J L; Hayes, A C & Navratil, P
Partner: UNT Libraries Government Documents Department
open access

Limits on the Superconducting Order Parameter in NdFeAsO_{1-x}F_y from Scanning SQUID Microscopy

Description: Identifying the symmetry of the superconducting order parameter in the recently-discovered ferrooxypnictide family of superconductors, RFeAsO{sub 1-x}F{sub y}, where R is a rare earth, is a high priority. Many of the proposed order parameters have internal {pi} phase shifts, like the d-wave order found in the cuprates, which would result in direction-dependent phase shifts in tunneling. In dense polycrystalline samples, these phase shifts in turn would result in spontaneous orbital currents and… more
Date: January 8, 2009
Creator: Hicks, Clifford W.; Lippman, Thomas M.; Huber, Martin E.; Ren, Zhi-An; Yang, Jie; Zhao, Zhong-Xian et al.
Partner: UNT Libraries Government Documents Department
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Probing Late Neutrino Mass Properties With SupernovaNeutrinos

Description: Models of late-time neutrino mass generation contain new interactions of the cosmic background neutrinos with supernova relic neutrinos (SRNs). Exchange of an on-shell light scalar may lead to significant modification of the differential SRN flux observed at earth. We consider an Abelian U(1) model for generating neutrino masses at low scales, and show that there are cases for which the changes induced in the flux allow one to distinguish the Majorana or Dirac nature of neutrinos, as well as th… more
Date: August 8, 2007
Creator: Baker, Joseph; Goldberg, Haim; Perez, Gilad & Sarcevic, Ina
Partner: UNT Libraries Government Documents Department
open access

Supercomputers: Super-polluters?

Description: Thanks to imperatives for limiting waste heat, maximizing performance, and controlling operating cost, energy efficiency has been a driving force in the evolution of supercomputers. The challenge going forward will be to extend these gains to offset the steeply rising demands for computing services and performance.
Date: April 8, 2008
Creator: Mills, Evan; Mills, Evan; Tschudi, William; Shalf, John & Simon, Horst
Partner: UNT Libraries Government Documents Department
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