Alignment of the High Beta Magnets in the RHIC Interaction Regions (open access)

Alignment of the High Beta Magnets in the RHIC Interaction Regions

This report talks about the Alignment of the High Beta Magnets in the RHIC Interaction Regions
Date: May 12, 1997
Creator: Trbojevic, D.; Jain, A.; Tepikian, S.; Grandetti, R.; Ganetis, G.; Wei, J. et al.
Object Type: Report
System: The UNT Digital Library
Biochemical Removal of HAP Precursors from Coal (open access)

Biochemical Removal of HAP Precursors from Coal

Column biooxidation tests with Kentucky coal confirmed results of earlier shake flask tests showing significant removal from the coal of arsenic, selenium, cobalt, manganese, nickel and cadmium. Rates of pyrite biooxidation in Kentucky coal were only slightly more than half the rates found previously for Indiana and Pittsburgh coals. Removal of pyrite from Pittsburgh coal by ferric ion oxidation slows markedly as ferrous ions accumulate in solution, requiring maintenance of high redox potentials in processes designed for removal of pyrite and hazardous air pollutant (HAP) precursors by circulation of ferric solutions through coal. The pyrite oxidation rates obtained in these tests were used by Unifield Engineering to support the conceptual designs for alternative pyrite and HAP precursor bioleaching processes for the phase 2 pilot plant. Thermophilic microorganisms were tested to determine if mercury could be mobilized from coal under elevated growth temperatures. There was no evidence for mercury removal from coal under these conditions. However, the activity of the organisms may have liberated mercury physically. It is also possible that the organisms dissolved mercury and it readsorbed to the clay preferentially. Both of these possibilities are undergoing further testing. The Idaho National Engineering and Environmental Laboratory�s (INEEL) slurry column reactor …
Date: May 12, 1997
Creator: Olson, Gregory J.
Object Type: Report
System: The UNT Digital Library
Change in Field Harmonics After Quench and Thermal Cycles in Superconducting Magnets (open access)

Change in Field Harmonics After Quench and Thermal Cycles in Superconducting Magnets

A change in field harmonics after quench and thermal cycles has been observed in superconducting magnets for the Relativistic Heavy Ion Collider (RHIC). This paper presents the results of a systematic investigation of this effect in a number of RHIC dipole and quadrupole magnets. These changes in field harmonics may limit the ultimate field quality and its reproducibility in superconducting magnets. A change in pre-stress has also been observed after quench and thermal cycles. A possible link between these two changes is explored.
Date: May 12, 1997
Creator: Gupta, R.; Jain, A.; Muratore, J.; Wanderer, P.; Willen, E. & Wyss, C.
Object Type: Article
System: The UNT Digital Library
DOE Order 5480.28, Natural phenomena hazards mitigation system, structure, component database (open access)

DOE Order 5480.28, Natural phenomena hazards mitigation system, structure, component database

This document describes the Prioritization Phase Database that was prepared for the Project Hanford Management Contractors to support the implementation of DOE Order 5480.28. Included within this document are three appendices which contain the prioritized list of applicable Project Hanford Management Contractors Systems, Structures, and Components. These appendices include those assets that comply with the requirements of DOE Order 5480.28, assets for which a waiver will be recommended, and assets requiring additional information before compliance can be ascertained.
Date: May 12, 1997
Creator: Conrads, T. J.
Object Type: Report
System: The UNT Digital Library
Electron Bunch Length Diagnostic With Coherent Smith-Purcell Radiation (open access)

Electron Bunch Length Diagnostic With Coherent Smith-Purcell Radiation

The authors have designed a new technique for measuring subpicosecond electron bunch lengths using coherent Smith-Purcell radiation. This new diagnostic technique involves passing the electron beam in close proximity of a grating with a period comparable to the electron bunch length. The emitted Smith-Purcell radiation will have a coherent component whose angular position and distribution are directly related to the electron bunch length and longitudinal profile, respectively. This new diagnostic technique is inherently simple, inexpensive and non-intercepting. The authors show that the new technique is also scaleable to femtosecond regime.
Date: May 12, 1997
Creator: Nguyen, D. C.
Object Type: Article
System: The UNT Digital Library
Electron concentration and phase stability in NbCr2-based Laves phase alloys (open access)

Electron concentration and phase stability in NbCr2-based Laves phase alloys

Phase stability in NbCr{sub 2}-based transition-metal Laves phases was studied, based on the data reported for binary X-Cr, Nb-X, and ternary Nb-Cr-X phase diagrams. It was shown that when the atomic size ratios are kept identical, the average electron concentration factor, e/a, is the dominating factor in controlling the phase stability of NbCr{sub 2}-based transition-metal Laves phases. The e/a ratios for different Laves polytypes were determined as followed: with e/a < 5.76, the C15 structure is stabilized; at an e/a range of 5.88--7.53, the C14 structure is stabilized; with e/a > 7.65, the C15 structure is stabilized again. A further increase in the electron concentration factor (e/a > 8) leads to the disordering of the alloy. The electron concentration effect on the phase stability of Mg-based Laves phases and transition-metal A{sub 3}B intermetallic compounds is also reviewed and compared with the present observations in transition-metal Laves phases. In order to verify the e/a/phase stability relationship experimentally, additions of Cu (with e/a = 11) were selected to replace Cr in the NbCr{sub 2} Laves phase. Experimental results for the ternary Nb-Cr-Cu system are reported and discussed in terms of the correlation between the e/a ratio and phase stability in NbCr{sub 2}-based …
Date: May 12, 1997
Creator: Zhu, J. H.; Liaw, P. K. & Liu, C. T.
Object Type: Report
System: The UNT Digital Library
A Helical Magnet Design for RHIC (open access)

A Helical Magnet Design for RHIC

Helical dipole magnets are required in a project for the Relativistic Heavy Ion Collider (RHIC) to control and preserve the beam polarization in order to allow the collision of polarized proton beams. Specifications are for low current superconducting magnets with a 100 mm coil aperture and a 4 Tesla field in which the field rotates 360 degrees over a distance of 2.4 meters. A magnet meeting the requirements has been developed that uses a small diameter cable wound into helical grooves machined into a thick-walled aluminum cylinder.
Date: May 12, 1997
Creator: Willen, E.; Gupta, R.; Jain, A.; Kelly, E.; Morgan, G.; Muratore, J. et al.
Object Type: Article
System: The UNT Digital Library
A Helical Magnet Design for RHIC (open access)

A Helical Magnet Design for RHIC

Helical dipole magnets are required in a project for the Relativistic Heavy Ion Collider (RHIC) to control and preserve the beam polarization in order to allow the collision of polarized proton beams. Specifications are for low current superconducting magnets with a 100 mm coil aperture and a 4 Tesla field in which the field rotates 360 degrees over a distance of 2.4 meters. A magnet meeting the requirements has been developed that uses a small diameter cable wound into helical grooves machined into a thick-walled aluminum cylinder.
Date: May 12, 1997
Creator: Willen, E.; Gupta, R.; Jain, A.; Kelly, E.; Morgan, G.; Muratore, J. et al.
Object Type: Article
System: The UNT Digital Library
Integration and baseline management training and transition plan (open access)

Integration and baseline management training and transition plan

The purpose of the Integration and Baseline Management Training and Transition Plan is to provide a training outline for the Integration and Baseline Management (I and BM) organization and a transition strategy for the Master Equipment List (MEL) Phase 1 application. The training outline includes the following courses: MEL Phase 1 Application Course 1 Master Equipment List General Overview. Course 2 Master Equipment List Editing. Tank Waste Remediation System (TWRS) Labeling Related Course 3 TWRS Equipment Labeling Program (Course Number 350545). As part of courses 1, 2, and 3, it is recommended that a lesson plan be developed and integrated into each of the three courses on the subject of Configuration Management (CM) to include: CM concepts, terminology, definitions, fundamentals and its application with respect to the course. The strategy for the MEL Phase 1 application is to train internal organizations (I and BM) on the MEL-General Overview for read only users and train MEL-Editing for edit users (only on an as needed basis). For external organizations, the strategy is to train selected personnel on the MEL-General Overview and transition them from read only privileges to editing privileges when the appropriate administrative procedures that outline the external organization`s responsibilities (to …
Date: May 12, 1997
Creator: Jech, J.B.
Object Type: Report
System: The UNT Digital Library
Investigation and deactivation of B Plant HEPA filters (open access)

Investigation and deactivation of B Plant HEPA filters

This paper describes the integrated approach used to manage environmental, safety, and health considerations related to the B Plant canyon exhaust air filters at the US Department of Energy (DOE) Hanford Site. The narrative illustrates the development and implementation of integrated safety management as applied to a facility and its systems undergoing deactivation. During their lifetime, the high efficiency particulate air (HEPA) filters prevented the release of significant quantities of radioactive materials into the air. As the material in B Plant AVESF accumulated on the filters, it created an unusual situation. Over long periods of time, the radiation dose from the filter loading, combined with aging and chemical exposure actually degrade those filters which were intended to protect against any release to the environment.
Date: May 12, 1997
Creator: Roege, P. E.
Object Type: Article
System: The UNT Digital Library
A Lattice for the Muon Collider Demonstration Ring in the RHIC Tunnel (open access)

A Lattice for the Muon Collider Demonstration Ring in the RHIC Tunnel

None
Date: May 12, 1997
Creator: Trbojevic, D.; Palmer, R. B.; Courant, E. D.; Gallardo, J.; Peggs, S.; Tepikian, S. et al.
Object Type: Report
System: The UNT Digital Library
Longitudinal Emittance Compensation in a Photocathode Rf Gun Injector. (open access)

Longitudinal Emittance Compensation in a Photocathode Rf Gun Injector.

None
Date: May 12, 1997
Creator: Wang, X. J. & Ben-Zvi, Ilan
Object Type: Article
System: The UNT Digital Library
Low-level RF signal processing for the Next Linear Collider Test Accelerator (open access)

Low-level RF signal processing for the Next Linear Collider Test Accelerator

In the X-band accelerator system for the Next Linear Collider Test Accelerator (NLCTA), the Low Level RF (LLRF) drive system must be very phase stable, but concurrently, be very phase agile. Phase agility is needed to make the Stanford Linear Doubler (SLED) power multiplier systems Energy work and to shape the RF waveforms to compensate beam loading in the accelerator sections. Similarly, precision fast phase and amplitude monitors are required to view, track, and feed back on RF signals at various locations throughout the system. The LLRF is composed of several subsystems: the RF Reference System generates and distributes a reference 11.424 GHz signal to all of the RF stations, the Signal Processing Chassis creates the RF waveforms with the appropriate phase modulation, and the Phase Detector Assembly measures the amplitude and phase of monitor3ed RF signals. The LLRF is run via VXI instrumentation. These instruments are controlled using HP VEE graphical programming software. Programs have been developed to shape the RF waveform, calibrate the phase modulators and demodulators, and display the measured waveforms. This paper describes these and other components of the LLRF system.
Date: May 12, 1997
Creator: Holmes, S.; Ziomek, C. & Adolphsen, C.
Object Type: Article
System: The UNT Digital Library
MAGNETIC DESIGN OF A HIGH GRADIENT QUADRUPOLE FOR THE LHC LOW B INSERTIONS. (open access)

MAGNETIC DESIGN OF A HIGH GRADIENT QUADRUPOLE FOR THE LHC LOW B INSERTIONS.

Fermilab, Lawrence Berkeley National Laboratory and Brookhaven National Laboratory have formed a consortium to provide components for the Large Hadron Collider (LHC) to be built at CERN. The U.S. contribution includes half of the high gradient quadrupoles (HGQ) for the inner focusing triplets. In this paper a description of the HGQ magnetic design is given, including short sample limit for field gradient, sources and expected values of systematic and random field errors, and possible strategies for field quality correction.
Date: May 12, 1997
Creator: Sabbi, G.; Gourlay, S. A.; Kerby, J.; Lamm, M. J.; Limon, P. J.; Nobrega, F. et al.
Object Type: Article
System: The UNT Digital Library
Mars ascent propulsion options for small sample return vehicles (open access)

Mars ascent propulsion options for small sample return vehicles

None
Date: May 12, 1997
Creator: Whitehead, J. C., LLNL
Object Type: Article
System: The UNT Digital Library
Metal colloids and quantum dots: linear and nonlinear optical properties (open access)

Metal colloids and quantum dots: linear and nonlinear optical properties

Nanophase materials have found a wide application in a variety of technological areas which include ultrafast optical switching high density information storage and retrieval, electronics, and catalysts, to mention a few. Nanocrystal science has also drawn considerable interest from the fundamental perspective engaging physicists, chemists, and material scientists into this area of rapidly expanding and challenging research. Basic questions concerning how matter evolves from atomic like behavior to molecular and onto bulk lie at the center nanocrystal research. In addition, because of the high surface to volume ratio of the nanocrystals, the interaction potential between a nanocrystal and its surrounding environment becomes an important issue in determining its properties. While significant progress has been made in nanocrystal research, there are many problems concerned with their fabrication. In particular, the difficulty of incorporating nanocrystals into a matrix that is appropriate for ultimate device development has hindered some aspects of nanocrystal research. Ion implantation is a method that is now established as a technique for fabricating metal and semiconductor nanocrystals. It is highly versatile in that one may select nearly any host material for incorporating the nanocrystals of interest. The flexibility of being able to select the host matrix is also interesting …
Date: May 12, 1997
Creator: Henderson, Don O.
Object Type: Report
System: The UNT Digital Library
Microwave Instability Thresholds. (open access)

Microwave Instability Thresholds.

None
Date: May 12, 1997
Creator: Zhang, S. Y.
Object Type: Article
System: The UNT Digital Library
An overview of the Low Energy Demonstration Accelerator (LEDA) project RF (radio frequency) systems (open access)

An overview of the Low Energy Demonstration Accelerator (LEDA) project RF (radio frequency) systems

Successful operation of the Accelerator Production of Tritium (APT) plant will require that accelerator downtime be kept to an absolute minimum. Over 230 separate 1 MW RF systems are expected to be used in the APT plant, making the efficiency and reliability of these systems two of the most critical factors in plant operation. The Low Energy Demonstration Accelerator (LEDA) being constructed at Los Alamos National Laboratory will serve as the prototype for APT. The design of the RF systems used in LEDA has been driven by the need for high efficiency and extremely high system reliability. The authors present details of the high voltage power supply and transmitter systems as well as detailed descriptions of the waveguide layout between the klystrons and the accelerating cavities. The first stage of LEDA operations will use four 1.2 MW klystrons to test the RFQ and supply power to one test stand. The RFQ will serve as a power combiner for multiple RF systems. They present some of the unique challenges expected in the use of this concept.
Date: May 12, 1997
Creator: Bradley, J., III; Cummings, K.; Lynch, M.; Rees, D.; Roybal, W.; Tallerico, P. et al.
Object Type: Article
System: The UNT Digital Library
Picosecond-Resolution "Slice" Emittance Measurement of Electron-Bunches. (open access)

Picosecond-Resolution "Slice" Emittance Measurement of Electron-Bunches.

The Slice Emittance diagnostic is applicable to particle bunches in a linac that are of the order of a few degrees of phase long. In this technique, the transverse phase space of a longitudinal slice about one degree long is measured. The Slice Emittance diagnostic has been demonstrated on an electron bunch produced by a laser-photocathode RF gun. We measured the transverse beam matrix of one picosecond slices out of a 10 picosecond long bunch (about 10 degrees at the RF frequency of 2856 MHz). To implement this diagnostic one needs a phase shifter on part of the linac, a momentum analyzer (a dipole magnet followed by a slit) and a transverse emittance measuring system following the analyzer. By dephasing the last section (or sections) of the linac, longitudinal position in the bunch is correlated with energy. The momentum analyzer selects a short longitudinal slice by discriminating on energy and the transverse phase space of this slice is measured downstream of the analyzer. The Slice Emittance diagnostic, particularly in conjunction with tomographic analysis of the transverse phase space of the slices, provides significant new information about the 6-D phase space distribution of the beam. The experimental work done with this …
Date: May 12, 1997
Creator: Ben-Zvi, Ilan; Qiu, Joe X. & Wang, Xijie
Object Type: Article
System: The UNT Digital Library
Point & Click: Internet Searching Techniques (open access)

Point & Click: Internet Searching Techniques

None
Date: May 12, 1997
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Polarization of atomic radiation in stochastic plasma fields (open access)

Polarization of atomic radiation in stochastic plasma fields

When a laser pulse of certain polarization or an electron beam excites atoms in a plasma, the atomic spectrum of the radiation emitted by the atoms exhibits differently polarized line core and line wings. This unusual effect, which is predicted to occur under a variety of conditions, can be accompanied by the appearance of the forbidden component in the spectrum, with polarization opposite to that of the exciting laser pulse.
Date: May 12, 1997
Creator: Savchenko, V. I. & Fisch, N. J.
Object Type: Report
System: The UNT Digital Library
The Pomeron beyond BFKL (open access)

The Pomeron beyond BFKL

Conformally invariant reggeon interactions derived from t-channel unitarity are discussed and progress towards understanding the {open_quotes}physical Pomeron{close_quotes}, via massless quark reggeon interactions, is briefly out-lined.
Date: May 12, 1997
Creator: White, A. R.
Object Type: Article
System: The UNT Digital Library
Preparing Accelerator Systems for the RHIC Sextant Commissioning (open access)

Preparing Accelerator Systems for the RHIC Sextant Commissioning

None
Date: May 12, 1997
Creator: D., Trbojevic
Object Type: Report
System: The UNT Digital Library
A Proton Driver for the Muon Collider Source with a Tunable Momentum Compaction Lattice (open access)

A Proton Driver for the Muon Collider Source with a Tunable Momentum Compaction Lattice

None
Date: May 12, 1997
Creator: Trbojevic, D.; Stevens, A. J. & Harrison, M.
Object Type: Report
System: The UNT Digital Library