Month

Language

Export Controls: Improvements to Commerce's Dual-Use System Needed to Ensure Protection of U.S. Interests in the Post-9/11 Environment (open access)

Export Controls: Improvements to Commerce's Dual-Use System Needed to Ensure Protection of U.S. Interests in the Post-9/11 Environment

A letter report issued by the Government Accountability Office with an abstract that begins "In regulating exports of dual-use items, which have both commercial and military applications, the Department of Commerce's Bureau of Industry and Security (BIS) seeks to allow U.S. companies to compete globally while minimizing the risk of items falling into the wrong hands. In so doing, BIS faces the challenge of weighing U.S. national security and economic interests, which at times can be divergent or even competing. In light of the September 2001 terror attacks, GAO was asked to examine BIS's dual-use export control system. In response, GAO is reporting on BIS's (1) evaluations of and changes to the system, (2) screening of export license applications against its watchlist, and (3) actions to correct weaknesses previously identified by GAO."
Date: June 26, 2006
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Personal Information: Key Federal Privacy Laws Do Not Require Information Resellers to Safeguard All Sensitive Data (open access)

Personal Information: Key Federal Privacy Laws Do Not Require Information Resellers to Safeguard All Sensitive Data

A letter report issued by the Government Accountability Office with an abstract that begins "The growth of information resellers--companies that collect and resell publicly available and private information on individuals--has raised privacy and security concerns about this industry. These companies collectively maintain large amounts of detailed personal information on nearly all American consumers, and some have experienced security breaches in recent years. GAO was asked to examine (1) financial institutions' use of resellers; (2) federal privacy and security laws applicable to resellers; (3) federal regulators' oversight of resellers; and (4) regulators' oversight of financial institution compliance with privacy and data security laws. To address these objectives, GAO analyzed documents and interviewed representatives from 10 information resellers, 14 financial institutions, 11 regulators, industry and consumer groups, and others."
Date: June 26, 2006
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
DENSITY-FUNCTIONAL CALCULATIONS OF ALPHA-Pu-Ga (Al) ALLOYS (open access)

DENSITY-FUNCTIONAL CALCULATIONS OF ALPHA-Pu-Ga (Al) ALLOYS

None
Date: June 26, 2006
Creator: Landa, A; Soderlind, P & Vitos, L
Object Type: Article
System: The UNT Digital Library
Commissioning of the Digital Transverse Bunch-by-Bunch Feedback System for the Tls. (open access)

Commissioning of the Digital Transverse Bunch-by-Bunch Feedback System for the Tls.

Multi-bunch instabilities degrade beam quality through increased beam emittance, energy spread and even beam loss. Feedback systems are used to suppress multi-bunch instabilities associated with the resistive wall of the beam ducts, cavity-like structures, and trapped ions. A new digital transverse bunch-by-bunch feedback system has recently been commissioned at the Taiwan Light Source, and has replaced the previous analog system. The new system has the advantages that it enlarges the tune acceptance and improves damping for transverse instability at high currents, such that top-up operation is achieved. After a coupled-bunch transverse instability was suppressed, more than 350 mA was successfully stored during preliminary commissioning. In this new system, a single feedback loop simultaneously suppresses both horizontal and vertical multi-bunch instabilities. Investigating the characteristics of the feedback loop and further improving the system performances are the next short-term goals. The feedback system employs the latest generation of field-programmable gate array (FPGA) processor to process bunch signals. Memory has been installed to capture up to 250 msec of bunch oscillation signal, considering system diagnostics suitable to support various beam physics studies.
Date: June 26, 2006
Creator: Hu, K. H.; Kuo, C. H.; Chou, P. J.; Lee, D.; Hsu, S. Y.; Chen, J. et al.
Object Type: Article
System: The UNT Digital Library
Esimation of field-scale thermal conductivities of unsaturatedrocks from in-situ temperature data (open access)

Esimation of field-scale thermal conductivities of unsaturatedrocks from in-situ temperature data

A general approach is presented here which allows estimationof field-scale thermal properties of unsaturated rock using temperaturedata collected from in situ heater tests. The approach developed here isused to determine the thermal conductivities of the unsaturated host rockof the Drift Scale Test (DST) at Yucca Mountain, Nevada. The DST wasdesigned to obtain thermal, hydrological, mechanical, and chemical (THMC)data in the unsaturated fractured rock of Yucca Mountain. Sophisticatednumerical models have been developed to analyze these THMC data. However,though the objective of those models was to analyze "field-scale" (of theorder of tens-of-meters) THMC data, thermal conductivities measured from"laboratory-scale" core samples have been used as input parameters.While, in the absence of a better alternative, using laboratory-scalethermal conductivity values in field-scale models can be justified, suchapplications introduce uncertainties in the outcome of the models. Thetemperature data collected from the DST provides a unique opportunity toresolve some of these uncertainties. These temperature data can be usedto estimate the thermal conductivity of the DST host rock and, given thelarge volume of rock affected by heating at the DST, such an estimatewill be a more reliable effective thermal conductivity value for fieldscale application. In this paper, thus, temperature data from the DST areused to develop an estimate …
Date: June 26, 2006
Creator: Mukhopadhyay, Sumit; Tsang, Yvonne W. & Birkholzer, Jens T.
Object Type: Article
System: The UNT Digital Library
[Email from Sherry Ringler to the WASP's Board of Directors and By-Laws Committee, June 26, 2006] (open access)

[Email from Sherry Ringler to the WASP's Board of Directors and By-Laws Committee, June 26, 2006]

Email from Sherry Ringler to members of the WASP's Board of Directors and By-Laws Committee containing Jean McCreery's report on the vote to hire an executive director and plans for the business meeting to be held at the WASP reunion in September.
Date: June 26, 2006
Creator: Ringler, Sherry
Object Type: Letter
System: The Portal to Texas History
[Email from Catherine Murphy to the WASP Board, June 26, 2006] (open access)

[Email from Catherine Murphy to the WASP Board, June 26, 2006]

Email from Catherine Murphy to the WASP Board discussing her concerns with the proposal to hire an executive director.
Date: June 26, 2006
Creator: Murphy, Catherine A.
Object Type: Letter
System: The Portal to Texas History
[Email from Sherry Ringler Responding to Catherine Murphy's Concerns, June 26, 2006] (open access)

[Email from Sherry Ringler Responding to Catherine Murphy's Concerns, June 26, 2006]

Email from Sherry Ringler to the WASP's Board of Directors and By-Laws Committee responding to Catherine Murphy's concerns with hiring an executive director to manage the WASP's affairs.
Date: June 26, 2006
Creator: Ringler, Sherry
Object Type: Letter
System: The Portal to Texas History
Texas Attorney General Opinion: GA-0441 (open access)

Texas Attorney General Opinion: GA-0441

Document issued by the Office of the Attorney General of Texas in Austin, Texas, providing an interpretation of Texas law. It provides the opinion of the Texas Attorney General, Greg Abbott, regarding a legal question submitted for clarification: Authority of a municipality to lease its oil, gas and mineral property and the terms under which it may do so.
Date: June 26, 2006
Creator: Texas. Attorney-General's Office.
Object Type: Text
System: The Portal to Texas History
300 Area D4 Project 2nd Quarter FY06 Building Completion Report (open access)

300 Area D4 Project 2nd Quarter FY06 Building Completion Report

This report documents the deactivation, decontamination, decommissioning, and demolition of 16 buildings in the 300 Area of the Hanford Site. The D4 of these facilities included characterization, engineering, removal of hazardous and radiologically contaminated materials, equipment removal, utility disconnection, deactivation, decontamination, demolition of the structure, and stabilization or removal of the remaining slab and foundation as appropriate.
Date: June 26, 2006
Creator: Smith, David S.
Object Type: Report
System: The UNT Digital Library
Vertical Beam Size Control in TLS and TPS (open access)

Vertical Beam Size Control in TLS and TPS

Vertical beam size control is an important issue in the light source operations. The horizontal-vertical betatron coupling and vertical dispersion were measured and corrected to small values in the TLS 1.5 GeV storage ring. Estimated beam sizes are compared with the measured values. By employing an effective transverse damping system, the vertical beam blow-up due to transverse coherent instabilities, such as the fast-ion beam instability, was suppressed. As a result, the light source is very stable. In NSRRC we are designing an ultra low emittance 3-GeV storage ring and its designed vertical beam size could be as small as a few microns. The ground and mechanic vibration effects, and coherent instabilities could spoil the expected photon brightness due to blow-up of the vertical beam size if not well taken care of. The contributions of these effects to vertical beam size increase will be evaluated and the counter measures to minimize them will be proposed and reported in this paper.
Date: June 26, 2006
Creator: Kuo, C. C.; Chen, J. R.; Chou, P. J.; Chang, H. P.; Hsu, K. T.; Luo, G. H. et al.
Object Type: Article
System: The UNT Digital Library
Criticality Safety Evaluation of a LLNL Training Assembly for Criticality Safety (TACS) (open access)

Criticality Safety Evaluation of a LLNL Training Assembly for Criticality Safety (TACS)

Hands-on experimental training in the physical behavior of multiplying systems is one of ten key areas of training required for practitioners to become qualified in the discipline of criticality safety as identified in DOE-STD-1135-99, ''Guidance for Nuclear Criticality Safety Engineer Training and Qualification''. This document is a criticality safety evaluation of the training activities (or operations) associated with HS-3200, ''Laboratory Class for Criticality Safety''. These activities utilize the Training Assembly for Criticality Safety (TACS). The original intent of HS-3200 was to provide LLNL fissile material handlers with a practical hands-on experience as a supplement to the academic training they receive biennially in HS-3100, ''Fundamentals of Criticality Safety'', as required by ANSI/ANS-8.20-1991, ''Nuclear Criticality Safety Training''. HS-3200 is to be enhanced to also address the training needs of nuclear criticality safety professionals under the auspices of the NNSA Nuclear Criticality Safety Program.
Date: June 26, 2006
Creator: Heinrichs, D P
Object Type: Report
System: The UNT Digital Library
BEAM TRANSPORT LINES FOR THE BSNS. (open access)

BEAM TRANSPORT LINES FOR THE BSNS.

This paper presents the design of two beam transport lines at the BSNS: one is the injection line from the Linac to the RCS and the other is the target line from the RCS to the target station. In the injection beam line, space charge effects, transverse halo collimation, momentum tail collimation and debunching are the main concerned topics. A new method of using triplet cells and stripping foils is used to collimate transverse halo. A long straight section is reserved for the future upgrading linac and debuncher. In the target beam line, large halo emittance, beam stability at the target due to kicker failures and beam jitters, shielding of back-scattering neutrons from the target are main concerned topics. Special bi-gap magnets will be used to reduce beam losses in the collimators in front of the target.
Date: June 26, 2006
Creator: WEI, J.
Object Type: Article
System: The UNT Digital Library
Fast Compensation of Global Linear Coupling in Rhic Using Ac Dipoles. (open access)

Fast Compensation of Global Linear Coupling in Rhic Using Ac Dipoles.

Global linear coupling has been extensively studied in accelerators and several methods have been developed to compensate the coupling coefficient C using skew quadrupole families scans. However, scanning techniques can become very time consuming especially during the commissioning of an energy ramp. In this paper they illustrate a new technique to measure and compensate, in a single machine cycle, global linear coupling from turn-by-turn BPM data without the need of a skew quadrupole scan. The algorithm is applied to RHIC BPM data using AC dipoles and compared with traditional methods.
Date: June 26, 2006
Creator: Calaga, R. & Franchi, A. (Gsi), Tomas, R.(Cern)
Object Type: Article
System: The UNT Digital Library
Procedures and Accuracy Estimates for Beta-Beat Correction in the Lhc. (open access)

Procedures and Accuracy Estimates for Beta-Beat Correction in the Lhc.

The LHC aperture imposes a tight tolerance of 20% on the maximum acceptable beta-beat in the machine. An accurate knowledge of the transfer functions for the individually powered insertion quadrupoles and techniques to compensate beta-beat are key prerequisites for successful operation with high intensity beams. They perform realistic simulations to identify quadrupole errors in LHC and explore possible ways of correction to minimize beta-beat below the 20% level.
Date: June 26, 2006
Creator: Tomas, R.; Bruning, O. (Cern); Calaga, R. & Peggs, S.
Object Type: Article
System: The UNT Digital Library
FURTHER DEVELOPMENT OF A LOW INDUCTANCE METAL VAPOR VACUUM ARC (LIZ-MEVVA) ION SOURCE. (open access)

FURTHER DEVELOPMENT OF A LOW INDUCTANCE METAL VAPOR VACUUM ARC (LIZ-MEVVA) ION SOURCE.

None
Date: June 26, 2006
Creator: Johnson, B. M.; Hershcovitch, A. & Al., Et
Object Type: Article
System: The UNT Digital Library
The MUCOOL RF Program (open access)

The MUCOOL RF Program

Efficient muon cooling requires high RF gradients in the presence of high (3T) solenoidal fields. The Muon Ionization Cooling Experiment (MICE) also requires that the x-ray production from these cavities is low, in order to minimize backgrounds in the particle detectors that must be located near the cavities. These cavities require thin Be windows to ensure the highest fields on the beam axis. In order to develop these cavities, the MUCOOL RF Program was started about 6 years ago. Initial measurements were made on a six-cell cavity and a single-cell pillbox, both operating at 805 MHz. We have now begun measurements of a 201 MHz pillbox cavity. This program has led to new techniques to look at dark currents, a new model for breakdown and a general model of cavity performance based on surface damage. The experimental program includes studies of thin Be windows, conditioning, dark current production from different materials, magnetic-field effects and breakdown.
Date: June 26, 2006
Creator: Norem, J.; Bross, A.; Moretti, A.; Norris, B.; Qian, Z.; Torun, Y. et al.
Object Type: Article
System: The UNT Digital Library
STATUS OF FAST IR ORBIT FEEDBACK AT RHIC. (open access)

STATUS OF FAST IR ORBIT FEEDBACK AT RHIC.

To compensate modulated beam-beam offsets caused by mechanical vibrations of IR triplet quadrupoles at frequencies around 10 Hz, a fast IR orbit feedback system has been developed. We report design considerations and recent status of the system.
Date: June 26, 2006
Creator: Montag, C.; Cupolo, J.; Glenn, J.; Litvinenko, V.; Marusic, A.; Meng, W. et al.
Object Type: Article
System: The UNT Digital Library
CHINA SPALLATION NEUTRON SOURCE ACCELERATORS: DESIGN, RESEARCH, AND DEVELOPMENT. (open access)

CHINA SPALLATION NEUTRON SOURCE ACCELERATORS: DESIGN, RESEARCH, AND DEVELOPMENT.

The China Spallation Neutron Source (CSNS) is a newly approved high-power accelerator project based on a H{sup -} linear accelerator and a rapid cycling synchrotron. During the past year, several major revisions were made on the design including the type of the front end, the linac frequency, the transport layout, the ring lattice, and the type of ring components. Here, we discuss the rationale of design revisions, status of the R&D efforts, and upgrade considerations.
Date: June 26, 2006
Creator: WEI, J.; FU, S. & FANG, S.
Object Type: Article
System: The UNT Digital Library
The Interactions of Surface Damage on RF Cavity Operation (open access)

The Interactions of Surface Damage on RF Cavity Operation

Studies of low frequency RF systems for muon cooling has led to a variety of new techniques for looking at dark currents, a new model of breakdown, and, ultimately, a model of RF cavity operation based on surface damage. We find that cavity behavior is strongly influenced by the spectrum of enhancement factors on field emission sites. Three different spectra are involved: one defining the initial state of the cavity, the second determined by the breakdown events, and the third defining the equilibrium produced as a cavity operates at its maximum field. We have been able to measure these functions and use them to derive a wide variety of cavity parameters: conditioning behavior, material, pulse length, temperature, vacuum, magnetic field, pressure, gas dependence. In addition we can calculate the dependence of breakdown rate on surface field and pulse length. This work correlates with data from Atom Probe Tomography. We will describe this model and new experimental data.
Date: June 26, 2006
Creator: Norem, J.; Hassanein, A.; Insepov, Z.; Moretti, A.; Qian, Z.; Bross, A. et al.
Object Type: Article
System: The UNT Digital Library
Possibilities for Nuclear Photo-Science with Intense Lasers (open access)

Possibilities for Nuclear Photo-Science with Intense Lasers

The interaction of intense laser light with relativistic electrons can produce unique sources of high-energy x rays and gamma rays via Thomson scattering. ''Thomson-Radiated Extreme X-ray'' (T-REX) sources with peak photon brightness (photons per unit time per unit bandwidth per unit solid angle per unit area) that exceed that available from world's largest synchrotrons by more than 15 orders of magnitude are possible from optimally designed systems. Such sources offer the potential for development of ''nuclear photo-science'' applications in which the primary photon-atom interaction is with the nucleons and not the valence electrons. Applications include isotope-specific detection and imaging of materials, inverse density radiography, transmutation of nuclear waste and fundamental studies of nuclear structure. Because Thomson scattering cross sections are small, < 1 barn, the output from a T-REX source is optimized when the laser spot size and the electron spot size are minimized and when the electron and laser pulse durations are similar and short compared to the transit time through the focal region. The principle limitation to increased x-ray or gamma-ray brightness is ability to focus the electron beam. The effects of space charge on electron beam focus decrease approximately linearly with electron beam energy. For this reason, …
Date: June 26, 2006
Creator: Barty, C. J.; Hartemann, F. V.; McNabb, D. P.; Messerly, M.; Siders, C.; Anderson, S. et al.
Object Type: Article
System: The UNT Digital Library
A Non-Scaling FFAG for Rare Isotopes Production. (open access)

A Non-Scaling FFAG for Rare Isotopes Production.

This is a report to demonstrate use of Non-Scaling Fixed-Field Alternating-Gradient (FFAG) accelerators [1] in acceleration of partially stripped ions of Uranium-238 for Rare Isotopes Production. This example assumes a beam final energy of 500 MeV/u with an average beam output current of 1 {micro}A-particle and a beam average power of 120 kWatt.
Date: June 26, 2006
Creator: Ruggiero, A. G.; Roser, T. & Trbojevic, D.
Object Type: Article
System: The UNT Digital Library
ALE3D Simulation of Heating and Violence in a Fast Cookoff Experiment with LX-10 (open access)

ALE3D Simulation of Heating and Violence in a Fast Cookoff Experiment with LX-10

We performed a computational and experimental analysis of fast cookoff of LX-10 (94.7% HMX, 5.3% Viton A) confined in a 2 kbar steel tube with reinforced end caps. A Scaled-Thermal-Explosion-eXperiment (STEX) was completed in which three radiant heaters were used to heat the vessel until ignition, resulting in a moderately violent explosion after 20.4 minutes. Thermocouple measurements showed tube temperatures as high as 340 C at ignition and LX-10 surface temperatures as high as 279 C, which is near the melting point of HMX. Three micro-power radar systems were used to measure mean fragment velocities of 840 m/s. Photonics Doppler Velocimeters (PDVs) showed a rapid acceleration of fragments over 80 {micro}s. A one-dimensional ALE3D cookoff model at the vessel midplane was used to simulate the heating, thermal expansion, LX-10 decomposition composition, and closing of the gap between the HE (High Explosive) and vessel wall. Although the ALE3D simulation terminated before ignition, the model provided a good representation of heat transfer through the case and across the dynamic gap to the explosive.
Date: June 26, 2006
Creator: McClelland, M. A.; Maienschein, J. L.; Howard, W. M.; Nichols, A. L.; deHaven, M. R. & Strand, O. T.
Object Type: Article
System: The UNT Digital Library
COMPARISON OF DOUBLE BEND AND TRIPLE BEND ACHROMATIC LATTICE STRUCTURES AND NSLS-II. (open access)

COMPARISON OF DOUBLE BEND AND TRIPLE BEND ACHROMATIC LATTICE STRUCTURES AND NSLS-II.

The Double Bend Achromatic (DBA) and the Triple Bend Achromatic (TBA) lattice have been studied rather extensively for use for the NSLS-II storage ring. The advantage of the TBA compared to the DBA in terms of emittance per period is well known. However, the DBA has the advantage of greater number of ID straight sections for the users and maybe easier to tune the dispersive section for reduced chromatic sextupole strength. We present a comparison of these lattices based on optimization of the non-linear driving terms using high order achromatic cancellation of driving terms of the nonlinear lattice.
Date: June 26, 2006
Creator: Kramer, S. L.; Krinsky, S. & Bengtsson, J.
Object Type: Article
System: The UNT Digital Library