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Notes on Luminosity Variation at ISABELLE (open access)

Notes on Luminosity Variation at ISABELLE

In the present ISABELLE design, the luminosity at each insertion will be the same, unless special efforts are taken to get a low-..beta.. insertion or reduced crossing angle. These can only change the luminosity by factors of 2 to 4 from insertion to insertion. An estimation of the range of desired luminosities is given.
Date: October 19, 1977
Creator: Herrera, J. C.; Marx, M.; Roe, B. & Rosenberg, E. I.
System: The UNT Digital Library
Tokamak Fusion Test Reactor neutral beam injection system vacuum chamber (open access)

Tokamak Fusion Test Reactor neutral beam injection system vacuum chamber

Most of the components of the Neutral Beam Lines of the Tokamak Fusion Test Reactor (TFTR) will be enclosed in a 50 cubic meter box-shaped vacuum chamber. The chamber will have a number of unorthodox features to accomodate both neutral beam and TFTR requirements. The design constraints, and the resulting chamber design, are presented.
Date: October 19, 1977
Creator: Pedrotti, L.R.
System: The UNT Digital Library
Ion-beam inertial fusion: the requirements posed by target and deposition physics (open access)

Ion-beam inertial fusion: the requirements posed by target and deposition physics

The demonstration of ICF scientific feasibility requires success in target design, driver development and target fabrication. Since these are interrelated, we present here some results of ion beam target studies and relate them to parameters of interest to ion accelerators. Ion deposition physics have long been a well known subject apart from high beam currents. Recent NRL experiments at up to 250 kA/cm/sup 2/ ions confirm the classical deposition physics now at current densities which are comparable to most ion targets. On the other hand, GSI data at low current density but 1 to 10 MeV/nucleon are continually being accumulated. They have yet to find anomalous results. Relying on target concepts outlined briefly, we report on the energy gain of ion-driven fusion targets as a function of input energy, ion ranges and focal spot radius. We also comment on some consequences of target gain versus driver and reactor requirements.
Date: October 19, 1981
Creator: Mark, J.W.K.
System: The UNT Digital Library
Delay line proportional chambers for the Fermilab external muon identifier (open access)

Delay line proportional chambers for the Fermilab external muon identifier

Thirty-nine one meter square proportional chambers with delay line readout were constructed for the external muon identifier of the Fermilab 15 foot bubble chamber. They provide X,Y,U(45/sup 0/) and T (avalanche time) information using a single wire plane, etched strip cathodes and nine amplifiers. They have a time resolution of +-27ns, single particle spatial resolution of +-2 to +-3mm and double particle resolution of approximately 2/sup 1///sub 2/ to 4cm. The energy accessible to each wire is limited so none of the wires in the first 25 chambers has broken since their installation in 1973 to 1974.
Date: October 19, 1977
Creator: Parker, S.; Orthel, J. & Marriner, J.
System: The UNT Digital Library
X-ray lines as a density diagnostic in DT plasmas near 100x solid density (open access)

X-ray lines as a density diagnostic in DT plasmas near 100x solid density

The use of electron impact broadened resonance lines to diagnose near-term high density diagnostics is discussed. In particular, the question of how to choose seed and pusher materials to have discernible broadening effects while maintaining line visibility is discussed.
Date: October 19, 1977
Creator: Bailey, D.S.
System: The UNT Digital Library
Neutral beam injection system for the Tokamak Fusion Test Reactor (open access)

Neutral beam injection system for the Tokamak Fusion Test Reactor

The Tokamak Fusion Test Reactor will be installed at the Princeton Plasma Physics Laboratory facility. This is a major step to reach the goal of fusion power using toroidal magnetic fields for plasma confinement. A major part of this test reactor will be four neutral beam injection systems. These systems will inject 20 MW of 120 kV neutral deuterium atoms into the plasma for 0.5 seconds. In order to achieve the required power input to the plasma, several systems are required within the neutral beam line. These are the source, neutralizer, ion deflection magnet, calorimeter and retraction system, ion dump, cryopumps and vacuum enclosure. All of these systems have constraints imposed which increase the complexity of their designs. Since all systems must operate in a tritium environment, remote handling capabilities must be incorporated into the design. An overview is presented of the Lawrence Livermore Laboratory/Lawrence Berkeley Laboratory Neutral Beam Injection System design. Specifications for the machine and a general description of the total system are presented.
Date: October 19, 1977
Creator: Pittenger, L.C.; Stone, R.R.; Valby, L.E. & Pedrotti, L.R.
System: The UNT Digital Library
System design for the new TMX machine (open access)

System design for the new TMX machine

The Tandem Mirror Experiment (TMX) is designed to test the physics of a new approach to Q-enhancement in open confinement systems. In the tandem mirror concept, the ends of a long solenoid are plugged electrostatically by means of ambipolar potential barriers created in two mirror machines or plugs, one at each end of the solenoid. The ambipolar potential in mirror machines develops as a consequence of the higher scattering rate of electrons and the balancing of electron and ion loss rates. The TMX experiment incorporates very few new engineering developments, but it does involve a new way of combining in an integrated system many previously developed ideas. The engineering task is to design the machine that would provide a proof-of-principle evaluation of the tandem mirror concept as rapidly as possible. The preliminary design was started in September 1976 and was completed by December 1976. It led to a cost estimate of $11 million and a scheduled construction period of 18 months.
Date: October 19, 1977
Creator: Chargin, A. K.; Calderon, M. O.; Mooney, L. J. & Vogtlin, G. E.
System: The UNT Digital Library
Investigation of Charge Transport Properties of CdZnTe Detectors with Synchrotron X-ray Radiation (open access)

Investigation of Charge Transport Properties of CdZnTe Detectors with Synchrotron X-ray Radiation

Various internal defects, such as Te inclusions, twin boundaries, dislocation, etc., are prevalent in as-grown CdZnTe (CZT) crystals, which affect the charge transport properties of CZT crystals and, therefore, worsen the performance of CZT detectors. In order to develop high quality CZT detectors, it is imperative to clarify the effects of internal defects on the charge transport properties of CZT. Simple flood illumination with nuclear radiation source cannot reveal the nature of highly localized defects in CZT. Therefore, at Brookhaven's National Synchrotron Light Source (NSLS), we have developed a unique testing system for micro-scale defect investigation of CZT, which employs an X-ray beam collimated with the spatial resolution as small as 3 x 3 {micro}m{sup 2}, a microscopic size comparable to the scale of common defects in CZT. This powerful tool enables us to investigate the effect of internal defects on charge transport properties of CZT in detail.
Date: October 19, 2008
Creator: Yang, G.; Bolotnikov, A. E.; Camarda, G. S.; Cui, Y.; Hossain, A. & James, R. B.
System: The UNT Digital Library
TRANSPARENCY: Tracking Uranium under the U.S. / Russian HEU Purchase Agreement (open access)

TRANSPARENCY: Tracking Uranium under the U.S. / Russian HEU Purchase Agreement

By the end of August, 2005, the Russia Federation delivered to the United States (U.S.) more than 7,000 metric tons (MT) of low enriched uranium (LEU) containing approximately 46 million SWU and 75,000 MT of natural uranium. This uranium was blended down from weapons-grade (nominally enriched to 90% {sup 235}U) highly enriched uranium (HEU) under the 1993 HEU Purchase Agreement that provides for the blend down of 500 MT HEU into LEU for use as fuel in commercial nuclear reactors. The HEU Transparency Program, under the National Nuclear Security Administration (NNSA), monitored the conversion and blending of the more than 250 MT HEU used to produce this LEU. The HEU represents more than half of the 500 MT HEU scheduled to be blended down through the year 2013 and is equivalent to the elimination of more than 10,000 nuclear devices. The HEU Transparency Program has made considerable progress in its mission to develop and implement transparency measures necessary to assure that Russian HEU extracted from dismantled Russian nuclear weapons is blended down into LEU for delivery to the United States. U.S. monitor observations include the inventory of in process containers, observation of plant operations, nondestructive assay measurements to determine {sup …
Date: October 19, 2005
Creator: Benton, J B; Decman, D J & Leich, D A
System: The UNT Digital Library
Good electrical contacts for high resistivity (Cd,Mn)Te crystals (open access)

Good electrical contacts for high resistivity (Cd,Mn)Te crystals

We consider that semi-insulating (Cd,Mn)Te crystals may well successfully replace the commonly used (Cd,Zn)Te crystals as a material for manufacturing large-area X- and gamma-ray detectors. The Bridgman growth method yields good quality and high-resistivity (10{sup 9}-10{sup 10} {Omega}-cm) crystals of (Cd,Mn)Te:V. Doping with vanadium ({approx} 10{sup 16} cm{sup -3}), which acts as a compensating agent, and annealing in cadmium vapors, which reduces the number of cadmium vacancies in the as-grown crystal, ensure this high resistivity. Detector applications of the crystals require satisfactory electrical contacts. Hence, we explored techniques of ensuring good electrical contacts to semi-insulating (Cd,Mn)Te crystals. Our findings are reported here. Before depositing the contact layers, we prepared an 'epi-ready' surface of the crystal platelet by a procedure described earlier for various tellurium-based II-VI compound crystals. A molecular beam epitaxy (MBE) apparatus was used to deposit various types of contact layers: Monocrystalline semiconductor layers, amorphous- and nanocrystalline semiconductor layers, and metal layers were studied. We employed ZnTe heavily doped ({approx} 10{sup 18} cm{sup -3}) with Sb, and CdTe heavily doped ({approx} 10{sup 17} cm{sup -3}) with In as the semiconductors to create contact layers that subsequently enable good contact (with a narrow, tunneling barrier) to the Au layer that …
Date: October 19, 2008
Creator: Witkowska-Baran, M.; Mycielski, A.; Kochanowska, D.; Szadkowski, A. J.; Jakiela, r.; Witkowska, B. et al.
System: The UNT Digital Library
Orbital HP-Clouds for Solving Schrödinger Equation in Quantum Mechanics (open access)

Orbital HP-Clouds for Solving Schrödinger Equation in Quantum Mechanics

Solving Schroedinger equation in quantum mechanics presents a challenging task in numerical methods due to the high order behavior and high dimension characteristics in the wave functions, in addition to the highly coupled nature between wave functions. This work introduces orbital and polynomial enrichment functions to the partition of unity for solution of Schroedinger equation under the framework of HP-Clouds. An intrinsic enrichment of orbital function and extrinsic enrichment of monomial functions are proposed. Due to the employment of higher order basis functions, a higher order stabilized conforming nodal integration is developed. The proposed methods are implemented using the density functional theory for solution of Schroedinger equation. Analysis of several single and multi-electron/nucleus structures demonstrates the effectiveness of the proposed method.
Date: October 19, 2006
Creator: Chen, J. S.; Hu, W. & Puso, M. A.
System: The UNT Digital Library
Interspecific Differences in Metabolic Rate and Metabolic Temperature Sensitivity Create Distinct Thermal Ecological Niches in Lizards (Plestiodon) (open access)

Interspecific Differences in Metabolic Rate and Metabolic Temperature Sensitivity Create Distinct Thermal Ecological Niches in Lizards (Plestiodon)

This article examines three congeneric lizards from the southeastern United States (Plestiodon fasciatus, P. inexpectatus, and P. laticeps) and hypothesizes that interspecific differences in metabolic temperature sensitivity locally segregates them across their total range.
Date: October 19, 2016
Creator: Watson, Charles M. & Burggren, Warren W.
System: The UNT Digital Library
Sodium pool fire model for CONACS code. [LMFBR] (open access)

Sodium pool fire model for CONACS code. [LMFBR]

The modeling of sodium pool fires constitutes an important ingredient in conducting LMFBR accident analysis. Such modeling capability has recently come under scrutiny at Westinghouse Hanford Company (WHC) within the context of developing CONACS, the Containment Analysis Code System. One of the efforts in the CONACS program is to model various combustion processes anticipated to occur during postulated accident paths. This effort includes the selection or modification of an existing model and development of a new model if it clearly contributes to the program purpose. As part of this effort, a new sodium pool fire model has been developed that is directed at removing some of the deficiencies in the existing models, such as SOFIRE-II and FEUNA.
Date: October 19, 1982
Creator: Yung, S.C.
System: The UNT Digital Library
Safety procedures for the MFTF sustaining-neutral-beam power supply (open access)

Safety procedures for the MFTF sustaining-neutral-beam power supply

The MFTF SNBPSS comprises a number of sources of potentially hazardous electrical energy in a small physical area. Power is handled at 80 kV dc, 80 A; 70 V dc, 4000 A; 25 V dc, 5500 A; 3 kV dc, 10 A; and 2 kV dc, 10 A. Power for these systems is furnished from two separate 480 V distribution systems and a 13.8 kV distribution system. A defense in depth approach is used; interlocks are provided in the hardware to make it difficult to gain access to an energized circuit, and the operating procedure includes precautions which would protect personnel even if no interlocks were working. The complexity of the system implies a complex operating procedure, and this potential complexity is controlled by presenting the procedure in a modular form using 37 separate checklists for specific operations. The checklists are presented in flowchart form, so contingencies can be handled at the lowest possible level without compromising safety.
Date: October 19, 1981
Creator: Wilson, J. H.
System: The UNT Digital Library
Constraints on the atmospheres of Type I supernovae (open access)

Constraints on the atmospheres of Type I supernovae

The Ca II absorption lines observed in the late time optical spectra of Type I supernovae are analyzed in the context of the /sup 56/Ni model. The analysis indicates that a metal rich atmosphere of mass approx. 0.2 M/sub solar mass/ surrounds the /sup 56/Ni core. This result is consistent with properties of the atmosphere derived from spectra near maximum light.
Date: October 19, 1981
Creator: Axelrod, T.S.
System: The UNT Digital Library
Computer simulation of superthermal transport for laser fusion (open access)

Computer simulation of superthermal transport for laser fusion

The relativistic multigroup diffusion equations describing superthermal electron transport in laser fusion plasmas were derived in an earlier UCRL. A successful numerical scheme based on these equations which is now being used to model laser fusion experiments is described.
Date: October 19, 1979
Creator: Kershaw, D.S.
System: The UNT Digital Library
Modeling of brine migration in halite (open access)

Modeling of brine migration in halite

Four different models of the migration process have been reviewed to determine their suitability as a working model. While there are several common factors in the models additional factors are included to account for several possible effects. The detail of each model leads to a certain degree of difficulty in applying the model to the problem at hand. One model predicts that inclusions smaller than 0.1 mm dimension probably will not migrate. The other models do not consider size as a factor. Thermal diffusion (Soret effect) is considered insignificant in three models, while in the fourth model it is added to the concentration diffusion term. The following conclusions are made: (1) Temperature is the most significant parameter in all models and must be known as a function of time, and distance from the canister. (2) All four models predict about the same migration velocity for a given set of conditions. For 100/sup 0/C and 1/sup 0/C/cm thermal gradient, the individual values are 3.0, 4.8, 5.6 and 6.4 mm/y. (3) The diffusion of ions through the brine inclusions is the rate controlling mechanism. (4) The difference between the thermal gradients in the liquid and in the solid should always be considered, …
Date: October 19, 1979
Creator: Cheung, H.; Fuller, M.E. & Gaffney, E.S.
System: The UNT Digital Library
Modeling of brine migration in halite (open access)

Modeling of brine migration in halite

When canisters containing radwastes are emplaced in a repository the heat produced by the decaying radwaste will cause moderate thermal gradients to develop which will cause the brine present in a halite medium (salt deposits) to accumulate around the canister. Four different models of the migration process have been reviewed to determine their suitability as a working model. One model predicts that inclusions smaller than 0.1 mm dimension probably will not migrate. The other models do not consider size as a factor. Thermal diffusion (Soret effect) is considered insignificant in three models, while in the fourth model it is added to the concentration diffusion term. The following conclusions can be made: Temperature is the most significant parameter in all models and must be known as a function of time, and distance from the canister. All four models predict about the same migration velocity for it is a given set of conditions; for 100/sup 0/C and 1/sup 0/C/cm thermal gradient, it is 3.0, 4.8, 5.6 and 6.4 mm/y. Diffusion of ions through the brine inclusions is the rate controlling mechanism. The difference between the thermal gradients in the liquid and in the solid should always be considered and is a function …
Date: October 19, 1979
Creator: Cheung, H.; Fuller, M.E. & Gaffney, E.S.
System: The UNT Digital Library
Transcript of the workshop to discuss plans for a National High Intensity Radioactive Nuclear Beam Facility (open access)

Transcript of the workshop to discuss plans for a National High Intensity Radioactive Nuclear Beam Facility

Following the First International Conference on Radioactive Nuclear Beams'' in Berkeley, a workshop was held on October 19, 1989 at the Lawrence Berkeley Laboratory to discuss plans for a National High Intensity Radioactive Nuclear Beam (RNB) Facility. The purpose of the workshop was -- after having discussed during the conference the physics question that can be addressed with RNBs -- to evaluate more concretely the possibilities for actually constructing such a facility in this country. It is becoming increasingly apparent that facility producing beams of radioactive nuclei with extreme neutron-to-proton ratios is of high scientific interest and technically feasible. It would allow the study of nuclear structure and astrophysical reactions very far from the line of stable nuclei, and could provide new possibilities of reaching the long-sought island of stability of superheavy nuclei. Such facilities are under advanced consideration in Japan and at CERN in Europe. This paper contains a slightly edited transcript of the tape recording that was made of the workshop.
Date: October 19, 1989
Creator: Nitschke, J.M. (ed.)
System: The UNT Digital Library
Potentially Hazardous Air Contaminants in the Home (open access)

Potentially Hazardous Air Contaminants in the Home

The health concerns of several substances likely to be encountered in the non-industrial indoor environment are discussed. Monitoring data and information on the health effects of CO, NO/sub 2/, formaldehyde, and radon are included. (JGB)
Date: October 19, 1982
Creator: Woodring, J. L.
System: The UNT Digital Library
A Dynamically Adaptive Arbitrary Lagrangian-Eulerian Method for Hydrodynamics (open access)

A Dynamically Adaptive Arbitrary Lagrangian-Eulerian Method for Hydrodynamics

A new method that combines staggered grid Arbitrary Lagrangian-Eulerian (ALE) techniques with structured local adaptive mesh refinement (AMR) has been developed for solution of the Euler equations. The novel components of the combined ALE-AMR method hinge upon the integration of traditional AMR techniques with both staggered grid Lagrangian operators as well as elliptic relaxation operators on moving, deforming mesh hierarchies. Numerical examples demonstrate the utility of the method in performing detailed three-dimensional shock-driven instability calculations.
Date: October 19, 2002
Creator: Anderson, R W; Pember, R B & Elliott, N S
System: The UNT Digital Library
Recent Test Results of the High Field Nb3Sn Dipole Magnet HD2 (open access)

Recent Test Results of the High Field Nb3Sn Dipole Magnet HD2

The 1 m long Nb{sub 3}Sn dipole magnet HD2, fabricated and tested at Lawrence Berkeley National Laboratory, represents a step towards the development of block-type accelerator quality magnets operating in the range of 13-15 T. The magnet design features two coil modules composed of two layers wound around a titanium-alloy pole. The layer 1 pole includes a round cutout to provide room for a bore tube with a clear aperture of 36 mm. After a first series of tests where HD2 reached a maximum bore field of 13.8 T, corresponding to an estimated peak field on the conductor of 14.5 T, the magnet was disassembled and reloaded without the bore tube and with a clear aperture increased to 43 mm. We describe in this paper the magnet training observed in two consecutive tests after the removal of the bore tube, with a comparison of the quench performance with respect to the previous tests. An analysis of the voltage signals recorded before and after training quenches is then presented and discussed, and the results of coil visual inspections reported.
Date: October 19, 2009
Creator: Ferracin, P.; Bingham, B.; Caspi, S.; Cheng, D. W.; Dietderich, D. R.; Felice, H. et al.
System: The UNT Digital Library
Megachannel. gamma. --. gamma. coincidence system using a PDP-8/E computer and moving-head disks (open access)

Megachannel. gamma. --. gamma. coincidence system using a PDP-8/E computer and moving-head disks

A megachannel pulse-height analysis system using a PDP-8/E computer and two moving-head disk memories has been developed. The system has a storage capacity of 220 memory locations, is capable of processing 1100 events/s, and provides on-line sorting and disk storage. An X- or Y-pulse-height spectrum in coincidence with one or several arbitrary pulse-height windows can be assembled in core for scope display and spectral analysis within 2 to 20 seconds. Reconstruction of a complete X- or Y-pulse-height spectrum requires about 3 minutes.
Date: October 19, 1976
Creator: Ruhter, W. D.; Camp, D. C.; Mann, L. G.; Niday, J. B. & Siemens, P. D.
System: The UNT Digital Library
Evaluation Of The Integrated Solubility Model, A Graded Approach For Predicting Phase Distribution In Hanford Tank Waste (open access)

Evaluation Of The Integrated Solubility Model, A Graded Approach For Predicting Phase Distribution In Hanford Tank Waste

The mission of the DOE River Protection Project (RPP) is to store, retrieve, treat and dispose of Hanford's tank waste. Waste is retrieved from the underground tanks and delivered to the Waste Treatment and Immobilization Plant (WTP). Waste is processed through a pretreatment facility where it is separated into low activity waste (LAW), which is primarily liquid, and high level waste (HLW), which is primarily solid. The LAW and HLW are sent to two different vitrification facilities and glass canisters are then disposed of onsite (for LAW) or shipped off-site (for HLW). The RPP mission is modeled by the Hanford Tank Waste Operations Simulator (HTWOS), a dynamic flowsheet simulator and mass balance model that is used for mission analysis and strategic planning. The integrated solubility model (ISM) was developed to improve the chemistry basis in HTWOS and better predict the outcome of the RPP mission. The ISM uses a graded approach to focus on the components that have the greatest impact to the mission while building the infrastructure for continued future improvement and expansion. Components in the ISM are grouped depending upon their relative solubility and impact to the RPP mission. The solubility of each group of components is characterized …
Date: October 19, 2012
Creator: Pierson, Kayla L.; Belsher, Jeremy D. & Seniow, Kendra R.
System: The UNT Digital Library