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Prospects for top at the Tevatron collider in the 1990's

Description: We calculated the signal and background rates for top masses of 90, 120, 150, and 180 GeV for both the CDF and D{null} detectors. This allowed us to determine the prospects for both discovery as well as detailed study of heavy top depending on the luminosity. We have focused on the leptons + jets and dilepton signatures. We also consider the question of tagging b-jets and how that should reduce background and help in making a mass determination. 8 refs., 5 figs., 5 tabs.
Date: January 1, 1989
Creator: Abachi, S.; Butler, J. (Fermi National Accelerator Lab., Batavia, IL (USA)); Baden, D. (Harvard Univ., Cambridge, MA (USA)); Barnett, B.; Matthews, J. A. (Johns Hopkins Univ., Baltimore, MD (USA)); Buchholz, D. (Northwestern Univ., Evanston, IL (USA)) et al.
Partner: UNT Libraries Government Documents Department
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Design of a pulsed switching magnet for the Bevalac

Description: The design and construction of a water cooled, pulsed, laminated core dipole magnet which has recently been installed at the Bevalac is described. This new, energy efficient magnet was funded by the DOE In-House Energy Management Program. The magnet has been specifically designed for maximum efficiency in power utilization and has replaced two dc powered magnets in the Bevalac switchyard. It will reduce energy usage by 747 MWh/yr, and it provides the capability of pulse-to-pulse switching in 0.… more
Date: March 1, 1989
Creator: Abbott, S.; Alonso, J.; Brown, J.; Kalnins, J.; Krebs, G. & Reimers, R.
Partner: UNT Libraries Government Documents Department
open access

Design of an integrally formed RFQ

Description: The design, construction and testing of a 410 MHz RFQ utilizing a new mechanical design concept has been completed at LBL. The RFQ is planned to be used at the Bevatron for injecting protons into the present heavy ion linac. The integral vane-cavity construction is a significant and unique feature of this RFQ design, wherein four walls with integral vanes are assembled to form the RFQ geometry. This design concept provides the capability of achieving precision vane alignment in minimal assembly… more
Date: March 1, 1989
Creator: Abbott, S.; Caylor, R.; Gough, R.; Howard, D.; MacGill, R. & Staples, J.
Partner: UNT Libraries Government Documents Department
open access

Survey of results from Brookhaven Experiment 802 at the AGS

Description: Brookhaven Experiment 802 (E-802) is a magnetic spectrometer experiment which is directed toward the measurement of particle momentum spectra and particle-particle correlations following reactions with 14.5 GeV/u O and Si ions. In addition to the spectrometer there are detectors to measure the transverse energy flow, longitudinal energy flow, and the multiplicity. These detectors can be used to characterize the particle spectra or correlated between themselves. Particle spectra have been obtain… more
Date: January 1, 1989
Creator: Abbott, T.; Akiba, Y.; Alburger, D.; Beavis, D.; Bloomer, M. A.; Bond, P. D. et al.
Partner: UNT Libraries Government Documents Department
open access

Using computer-based training to facilitate radiation protection review

Description: In a national laboratory setting, it is necessary to provide radiation protection overview and training to diverse parts of the laboratory population. This includes employees at research reactors, accelerators, waste facilities, radiochemical isotope processing, and analytical laboratories, among others. In addition, our own radiation protection and monitoring staffs must be trained. To assist in the implementation of this full range of training, ORNL has purchased prepackaged computer-based tr… more
Date: January 1, 1989
Creator: Abercrombie, J. S. & Copenhaver, E. D.
Partner: UNT Libraries Government Documents Department
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A manual accountability system designed to reduce operator error

Description: At the Savannah River Plant, the separations areas are not equipped with automated accountability systems, therefore accountability is performed manually. Several years ago, the Computer Systems Engineering group was requested to develop a computerized accountability system for the separations areas that would rely on manual entry and perform the necessary computations, adjust and maintain the books, and generate the necessary reports. In addition, the system would provide a complete audit trai… more
Date: January 1, 1989
Creator: Abramczyk, M R
Partner: UNT Libraries Government Documents Department
open access

Z sup 0 physics from the Mark II at the SLC (SLAC Linear Collider)

Description: The MARK II detector has started to take data at the new SLAC Linear Collider. The novel aspects of the accelerator and of the MARK II are briefly described. Displays of event pictures from some of the early-on data are presented to illustrate the quality of the data. A first presentation of the results of an energy scan near the Z{sup 0} mass that is currently in progress shows the expected resonant enhancement near 91 GeV. 2 refs., 23 figs., 1 tab.
Date: June 1, 1989
Creator: Abrams, G.S. (Lawrence Berkeley Lab., CA (USA))
Partner: UNT Libraries Government Documents Department
open access

Status report on an engineering design study of hermetic liquid argon calorimetry for the SSC (Superconducting Super Collider)

Description: There is general recognition that engineering issues are critical to the viability of liquid argon calorimetry (LAC) at the Superconducting Super Collider (SSC). We have undertaken to quantitatively address these issues and, if possible, perform a preliminary design of a proof of principle'' LAC for SSC. To establish LAC as viable at SSC, we must demonstrate that the physics performance of the device is acceptable, despite the presence of dead material due to vessels and support structure. Our … more
Date: January 1, 1989
Creator: Adams, T.; Davis, M.; DiGiacomo, N.J.; Easom, B.; Gordon, H.; Hupp, J. et al.
Partner: UNT Libraries Government Documents Department
open access

A scanning photoelectron microscope (SPEM) at the National Synchrotron Light Source (NSLS)

Description: We are in the process of developing and commissioning a scanning photoelectron microscope (SPEM) at the X1A beamline of the National Synchrotron Light Source (NSLS). It is designed to make use of the Soft X-ray Undulator (SXU) at the NSLS. This high brightness source illuminates a Fresnel zone plate, which forms a focused probe, {<=} 0.2{mu}m in size, on the specimen surface. A grating monochromator selects the photon energy in the 400-800 eV range with an energy resolution of better than 1 eV.… more
Date: January 1, 1989
Creator: Ade, Harald; Kirz, Janos; Hulbert, Steve; Johnson, Erik; Anderson, Erik & Kern, Dieter
Partner: UNT Libraries Government Documents Department
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Scanning Photoelectron Microscope (SPEM) with a zone plate generated microprobe

Description: We describe instrumentation of a scanning photoelectron microscope (SPEM), which we are presently developing and commissioning at the X1A beamline of the National Synchrotron Light Source (NSLS). This instrument is designed to use the Soft X-ray Undulator (SXU) at the NSLS as a high brightness source to illuminate a Fresnel zone plate, thus forming a finely focused probe, {le} 0.2{mu}m in size, on the specimen surface. A grating monochromator selects the photon energy in the 400-800 eV range wi… more
Date: January 1, 1989
Creator: Ade, Harald; Kirz, Janos; Hulbert, Steve; Johnson, Erik; Anderson, Erik & Kern, Dieter
Partner: UNT Libraries Government Documents Department
open access

Recent results on hadronic D/sub s/ and D meson decays from the Mark III

Description: Recent results on hadronic D/sub s/ and D decays from the Mark III collaboration are presented. The absolute branching ratio B(D/sub s//sup +/ /yields/ /phi//pi//sup +/) is studied by searching for fully reconstructed e/sup +/e/sup /minus// /yields/ D/sub s/*/sup /plus minus//D/sub s//sup /minus plus// events using seven hadronic decay modes of the D/sub s//sup +/. A limit of B(D/sub s//sup +/ /yields/ /phi//pi//sup +/) < 4.1% at 90% C.L. is obtained. Evidence is presented for the decay D/sub s… more
Date: July 1, 1989
Creator: Adler, J.; Bai, Z.; Blaylock, G. T.; Bolton, T.; Brient, J. C.; Browder, T. E. et al.
Partner: UNT Libraries Government Documents Department
open access

Chemical and nuclear emergencies: Interchanging lessons learned from planning and accident experience

Description: Because the goal of emergency preparedness for both chemical and nuclear hazards is to reduce human exposure to hazardous materials, this paper examines the interchange of lessons learned from emergency planning and accident experience in both industries. While the concerns are slightly different, sufficient similarity is found for each to draw implications from the others experience. Principally the chemical industry can learn from the dominant planning experience associated with nuclear power… more
Date: January 1, 1989
Creator: Adler, V.; Sorensen, J.H. & Rogers, G.O.
Partner: UNT Libraries Government Documents Department
open access

Beam-based alignment technique for the SLC (Stanford Linear Collider) linac

Description: Misalignment of quadrupole magnets and beam position monitors (BPMs) in the linac of the SLAC Linear Collider (SLC) cause the electron and positron beams to be steered off-center in the disk-loaded waveguide accelerator structures. Off-center beams produce wakefields which limit the SLC performance at high beam intensities by causing emittance growth. Here, we present a general method for simultaneously determining quadrupole magnet and BPM offsets using beam trajectory measurements. Results fr… more
Date: March 1, 1989
Creator: Adolphsen, C. E.; Lavine, T. L.; Atwood, W. B.; Himel, T. M.; Lee, M. J.; Mattison, T. S. et al.
Partner: UNT Libraries Government Documents Department
open access

An alignment method for the Mark II silicon strip vertex detector using an x-ray beam

Description: A silicon strip vertex detector consisting of 36 independent detector modules is being constructed for use in the Mark II detector at the SLAC Linear Collider. This paper describes a method for determining the relative alignment of the modules to a precision better than the 5 ..mu..m intrinsic resolution of the detectors. The basic procedure involves moving the vertex detector by known amounts through a fixed, collimated x-ray beam, and using the beam position reconstructed from the detected si… more
Date: April 1, 1989
Creator: Adolphsen, C.; Gratta, G.; Labarga, L.; Litke, A.; Schwarz, A.; Turala, M. et al.
Partner: UNT Libraries Government Documents Department
open access

Chemistry of nitromethane at very high pressure

Description: Decomposition of nitromethane is reported over the range of 115- 180/degree/C and 0.6-8.5 GPa. About 5 /mu/g of nitromethane is compressed with a diamond-anvil cell, heated to the point that reaction occurs, and held typically 10-20 minutes at the reaction temperature. The cell is cooled and the volatile contents of the cell are frozen as a thin layer in vacuo and an infrared absorption spectrum is recorded. The three volatile products observed are N/sub 2/O, CO/sub 2/, and water, with N/sub 2/… more
Date: January 1, 1989
Creator: Agnew, S.F.; Swanson, B.I.; Kenney, J. & Kenney, I.
Partner: UNT Libraries Government Documents Department
open access

Reflection Asymmetric Shapes in Nuclei

Description: Experimental data show that there is no even-even nucleus with a reflection asymmetric shape in its ground state. Maximum octupole- octupole correlations occur in nuclei in the mass 224 (N{approximately}134, Z{approximately}88) region. Parity doublets, which are the characteristic signature of octupole deformation, have been observed in several odd mass Ra, Ac and Pa nuclei. Intertwined negative and positive parity levels have been observed in several even-even Ra and Th nuclei above spin {appr… more
Date: January 1, 1989
Creator: Ahmad, I.; Carpenter, M. P.; Emling, H.; Holzmann, R.; Janssens, R. V. F.; Khoo, T. L. et al.
Partner: UNT Libraries Government Documents Department
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Nuclear Shapes from Spectroscopic Studies of Fission Fragments

Description: Partial level schemes for several neutron-rich Ba and Ce nuclei have been determined from the study of gamma-gamma coincidences in /sup 252/Cf fission fragments. The experiment was performed with the Argonne-Notre Dame gamma ray facility, which consisted of 7 Compton- suppressed Ge detectors, a low-energy photon spectrometer and an inner ball of fourteen hexagonal BGO detectors. Gamma-gamma coincidence events between the Ge detectors, which were accompanied by a gamma in BGO detectors, were acc… more
Date: January 1, 1989
Creator: Ahmad, I.; Emling, H.; Holzmann, R.; Janssens, R.V.F.; Khoo, T.L.; Phillips, W.R. et al.
Partner: UNT Libraries Government Documents Department
open access

Transient Diffusion From a Waste Solid Into Water-Saturated, Fractured Porous Rock

Description: Numerical illustrations for transient mass transfer from an infinitely long cylinder intersected by a planar fracture are shown based on Chambre's exact analytical solutions. The concentration at the cylinder surface is maintained at the solubility. In the fracture contaminant diffuses in the radial direction. In the rock matrix three-dimensional diffusion is assumed in the cylindrical coordinate. No advection is assumed. Radioactive decay and sorption equilibrium are included. Radioactive deca… more
Date: September 1989
Creator: Ahn, J.; Chambre, P. L.; Pigford, T. H. & Lee, W. W. L.
Partner: UNT Libraries Government Documents Department
open access

Effects of Spatial Attention on the Visual-Evoked Neuromagnetic Response

Description: A number of studies have shown that selective attention to spatial location modulates the amplitudes of several visual evoked potential components recorded from posterior regions of the head (e.g., Eason, Harter White, 1969; Harter, Aine, Schroeder, 1982; Hillyard Munte, 1984; Mangun Hillyard, 1988). The early components, P1 and N1 (peak latencies: 90--135 and 140--170 msec, respectively), are thought to arise in one or more areas of visual cortex. Although it is generally assumed that such ERP… more
Date: January 1, 1989
Creator: Aine, C. J.; George, J. S.; Oakley, M. T.; Medvick, P. A. & Flynn, E. R.
Partner: UNT Libraries Government Documents Department
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Transient visual evoked neuromagnetic responses: Identification of multiple sources

Description: Neuromagnetic measurements and associated modeling procedures must be able to resolve multiple sources in order to localize and accurately characterize the generators of visual evoked neuromagnetic activity. Workers have identified at least 11 areas in the macaque, throughout occipital, parietal, and temporal cortex, which are primarily or entirely visual in function. The surface area of the human occipital lobe is estimated to be 150--250cm. Primary visual cortex covers approximately 26cm/sup … more
Date: January 1, 1989
Creator: Aine, C.; George, J.; Medvick, P.; Flynn, E.; Bodis-Wollner, I. & Supek, S.
Partner: UNT Libraries Government Documents Department
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Heat of detonation, the cylinder test, and performance munitions

Description: Heats of detonation of CHNO explosives correlate well with copper cylinder test expansion data. The detonation products/calorimetry data can be used to estimate performance in the cylinder test, in munitions, and for new molecules or mixtures of explosives before these are made. Confidence in the accuracy of the performance estimates is presently limited by large deviations of a few materials from the regression predictions; but these same deviations, as in the insensitive explosive DINGU and t… more
Date: January 1, 1989
Creator: Akst, I.B.
Partner: UNT Libraries Government Documents Department
open access

Small scale structure on cosmic strings

Description: I discuss our current understanding of cosmic string evolution, and focus on the question of small scale structure on strings, where most of the disagreements lie. I present a physical picture designed to put the role of the small scale structure into more intuitive terms. In this picture one can see how the small scale structure can feed back in a major way on the overall scaling solution. I also argue that it is easy for small scale numerical errors to feed back in just such a way. The intuit… more
Date: October 30, 1989
Creator: Albrecht, Andreas
Partner: UNT Libraries Government Documents Department
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Fluctuations in the density of charged particles in 200 A GeV /sup 16/O + (C, Au) collisions

Description: Data from 200 A GeV /sup 16/O + (C, Au) reactions are presented. The local fluctuations in the pseudo-rapidity density charged particles were studied with the method of scaled factorial moments. The extracted moments, <F/sub i/>, are found to be proportional to a power of the size of the pseudo-rapidity interval, /delta//eta/. Slopes were determined from the linear relation ln<F/sub i/> = a/sub i/ /minus/ /phi//sub i/ln/delta//eta/ and their dependence on impact parameter and multiplicity of ch… more
Date: January 1, 1989
Creator: Albrecht, R.; Awes, T. C.; Baktash, C.; Beckmann, P.; Berger, F.; Bock, R. et al.
Partner: UNT Libraries Government Documents Department
open access

A hypervelocity projectile launcher for well perforation

Description: Current oil well perforation techniques use low- to medium-velocity gun launchers for completing wells in soft rock. Shaped-charge jets are normally used in harder, more competent rock. A device to create a much higher velocity projectile was designed. This launcher will provide an alternative technique to be used when the conventional devices do not yield the maximum well performance. It is an adaptation of the axial cavity in a high explosive (HE) annulus design, with the axial cavity being f… more
Date: January 1, 1989
Creator: Albright, J. N.; Fugelso, L. E.; Lagner, G. C. & Burns, K. L.
Partner: UNT Libraries Government Documents Department
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