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Passive magnetic bearings for vehicular electromechanical batteries

Description: This report describes the design of a passive magnetic bearing system to be used in electromechanical batteries (flywheel energy storage modules) suitable for vehicular use. One or two such EMB modules might, for example, be employed in a hybrid-electric automobile, providing efficient means for power peaking, i.e., for handling acceleration and regenerative braking power demands at high power levels. The bearing design described herein will be based on a ''dual-mode'' operating regime.
Date: March 1, 1996
Creator: Post, R
Partner: UNT Libraries Government Documents Department

Neutrino beam line optics study

Description: A study was done to understand the beam line optics from the beginning of Switchyard all the way to the end of Neutrino beam line. All available SWIC data were taken to get the beam centroid and width to be used in the analysis. The beam emittance and lattice function at the beginning of beam line can also be inferred from the study. The result indicated that the normalized 95% emittance to be around 15 {pi}-mm-mr for the vertical plane and about 28 {pi}-mm-mr for the horizontal plane.
Date: September 1, 1996
Creator: Yang, Ming-Jen
Partner: UNT Libraries Government Documents Department

Effect of Opening Helix on Flying Wire Emittance Measurements

Description: It has been noted for some time that after the protons are injected, when the helix is opened the proton normalized vertical emittance (as measured by the flying wires) increases by about two {pi} mm-mr. The horizontal emittance decreases by about the same amount. This has been recognized as a false result, but there has been uncertainty as to whether it was due to the flying wires not measuring the beam sigma correctly when the beam center moved at the wires or whether the effective beta at the wires changed when the helix was opened and the orbit changed all around the machine. This study attempts to answer that question. The study took place Sunday, Feb. 25, 1996, from 18:30 to 22:30. The study consisted of injecting P1, P2 and P3 as normal, coalesced bunches and P4 and P5 as uncoalesced bunch trains of nominally 11 bunches. The purpose in using more than a single bunch was to increase statistical sampling and to investigate whether there was any significant difference between coalesced and uncoalesced bunches. Because the injection kicker had a long flat-top for 36 bunch studies, P6 could not be injected and when P5 was injected, P1 emittance increased by about two {pi} mm-mr. The flying wires were flown several times, the helix was turned on, the wires flown several times, the helix turned off, and the wires flown several times. The helix cycling was performed by knobbing the power supplies to avoid any possible emittance dilution from a non-adiabatic change. note that during the helix off state during helix cycling, one of the power supplies for the horizontal separators was inadvertently not turned down to zero, leaving the horizontal part of the helix at {approx} 16% of normal. After three cycles of helix on-off, a local horizontal three ...
Date: April 1, 1996
Creator: Pruss, Stan
Partner: UNT Libraries Government Documents Department

Tevatron anti-proton injection kicker waveform analysis

Description: This note describes the measurements of the waveform of the Tevatron antiproton injection kicker using the 150 Gev proton beam. This new horizontal kicker was installed at D48 during the summer of 1995 shutdown. These measurements were taken in two sessions [1] starting on October 10 and October 18, 1995. The measurements use the Tevatron BPM and flying wire systems. This note is a companion to the Tevatron proton injection kicker note published recently [2]. The design specifications for the kicker are given in Dinkel et al. [3].
Date: August 1, 1996
Creator: Hanna, B.; Finley, D. & /Fermilab
Partner: UNT Libraries Government Documents Department

Tickling C:AQ5

Description: The alignment of the quadrupoles in a proton synchrotron is important and the alignment of the low beta quadrupoles in collider mode is even more critical. One of the important considerations is the relationship of the electric center of the Beam Position Monitors (BPMs) to the magnetic center of quadrupoles. Determining this involves measurements when the elements are not in the tunnel and careful alignment utilizing external reference marks when the BPMs are not physically attached to the quadrupole. Even when the BPM is attached to the quadrupole (and calibrated), systematic offsets can be introduced by cable mismatch or slight imbalances in the monitoring electronics. A method has been implemented at Cern [1,2] to determine this relationship using the beam itself. TM-1960 described a proof of principle experiment at the Tevatron using one of the individually powered quadrupoles near the B0 interaction region whose ACNET name is C:AQ7. This short note demonstrates that they can perform the same analysis on a set of quadrupoles powered by a single power supply without having to worry about exciting a single quadrupole.
Date: January 1, 1996
Creator: Moore, Craig D.; Pfeffer, H. & /Fermilab
Partner: UNT Libraries Government Documents Department

Anti-proton tune measurements for the Fall 1995 accelerator studies

Description: A system to measure the tunes of a single antiproton (or proton) bunch was built and has been commissioned. The system achieved high sensitivity with a novel closed-orbit suppression system. The use of high bandwidth directional pickpus and kickers in conjunction with precise timing gates enabled the measurement of the tune of a single bunch.
Date: April 1, 1996
Creator: Marriner, john & /Fermilab
Partner: UNT Libraries Government Documents Department

Measurement of tune spread in the Tevatron versus octupole strength

Description: An experiment was performed in the Tevatron to measure the tune spread versus octupole strength. The experiment is sensitive to the relationship between octupole strength and current in the T:OZF circuit and to the octupole (and other non-linear focusing fields) in the Tevatron. The major motivation for the experiment was to determine the value of octupole excitation that minimizes the tune spread: this value is an estimate of the value required to obtain ''zero'' total octupole excitation in the extraction process. The experiment was performed using the strip-line kickers at A17 and the resonant Schottky pickups. The horizontal proton kicker was excited with a sine-wave from a vector signal analyzer (HP-89440A) and the horizontal proton signal was received. The gating circuitry normally used to select proton or antiproton bunches was by-passed. The response function was measured and recorded on a floppy disk. Measurements were initially made with a 200 Hz span (0.250 Hz frequency bins) and later with a 100 Hz span (0.125 Hz frequency bins).
Date: August 1, 1996
Creator: Marriner, John; Martens, Mike & /Fermilab
Partner: UNT Libraries Government Documents Department

Calibration of a Solar Absolute Cavity Radiometer with Traceability to the World Radiometric Reference

Description: This report describes the present method of establishing traceability of absolute cavity radiometers to the World Radiometric Reference (WRR) through the process employed in the International Pyrheliometer Comparisons (IPC). This method derives the WRR reduction factor for each of the participating cavity radiometers. An alternative method is proposed, described, and evaluated as a way to reduce the uncertainty in the comparison process. The two methods are compared using a sample of data from the recent IPC-VIII conducted from September 25th to October 13th, 1995 at the World Radiation Center in Davos, Switzerland. A description of absolute cavity radiometers is also included, using a PMO-6 as an example of active cavity radiometers, and a HF as an example of passive cavity radiometers.
Date: January 1, 1996
Creator: Reda, I.
Partner: UNT Libraries Government Documents Department

Subdivision, Subsurface Stratigraphy, and Estimated Age of Fluvial-Terrace Deposits in Northwestern Tennessee

Description: This report studies the fluvial-terrace deposits in northwestern Tennessee with the intention of establishing a means of correlating disjunct terrace segments along the Obion River that is independent of terrace height, to document the stratigraphy of selected terrace deposits, and to estimate their numerical ages.
Date: 1996
Creator: Rodbell, Donald T.
Partner: UNT Libraries Government Documents Department

Hybrid energy system cost analysis: San Nicolas Island, California

Description: This report analyzes the local wind resource and evaluates the costs and benefits of supplementing the current diesel-powered energy system on San Nicolas Island, California (SNI), with wind turbines. In Section 2.0 the SNI site, naval operations, and current energy system are described, as are the data collection and analysis procedures. Section 3.0 summarizes the wind resource data and analyses that were presented in NREL/TP 442-20231. Sections 4.0 and 5.0 present the conceptual design and cost analysis of a hybrid wind and diesel energy system on SNI, with conclusions following in Section 6. Appendix A presents summary pages of the hybrid system spreadsheet model, and Appendix B contains input and output files for the HYBRID2 program.
Date: July 1, 1996
Creator: Olsen, T. L. & McKenna, E.
Partner: UNT Libraries Government Documents Department

Waste certification program plan for Oak Ridge National Laboratory

Description: This document defines the waste certification program being developed for implementation at Oak Ridge National Laboratory (ORNL). The document describes the program structure, logic, and methodology for certification of ORNL wastes. The purpose of the waste certification program is to provide assurance that wastes are properly characterized and that the Waste Acceptance Criteria (WAC) for receiving facilities are met. The program meets the waste certification requirements outlined in U.S. Department of Energy (DOE) Order 5820.2A, Radioactive Waste Management, and ensures that 40 CFR documentation requirements for waste characterization are met for mixed (both radioactive and hazardous) and hazardous (including polychlorinated biphenyls) waste. Program activities will be conducted according to ORNL Level 1 document requirements.
Date: September 1, 1996
Creator: Kornegay, F. C.
Partner: UNT Libraries Government Documents Department

Evaluation of gasification and novel thermal processes for the treatment of municipal solid waste

Description: This report identifies seven developers whose gasification technologies can be used to treat the organic constituents of municipal solid waste: Energy Products of Idaho; TPS Termiska Processor AB; Proler International Corporation; Thermoselect Inc.; Battelle; Pedco Incorporated; and ThermoChem, Incorporated. Their processes recover heat directly, produce a fuel product, or produce a feedstock for chemical processes. The technologies are on the brink of commercial availability. This report evaluates, for each technology, several kinds of issues. Technical considerations were material balance, energy balance, plant thermal efficiency, and effect of feedstock contaminants. Environmental considerations were the regulatory context, and such things as composition, mass rate, and treatability of pollutants. Business issues were related to likelihood of commercialization. Finally, cost and economic issues such as capital and operating costs, and the refuse-derived fuel preparation and energy conversion costs, were considered. The final section of the report reviews and summarizes the information gathered during the study.
Date: August 1, 1996
Creator: Niessen, W. R.; Marks, C. H. & Sommerlad, R. E.
Partner: UNT Libraries Government Documents Department

Early operating and reliability experience with the CEBAF DC magnet power supplies

Description: The CEBAF accelerator is a five pass, recirculating, CW electron linear accelerator. There are a total of nine recirculation arcs connecting the two linacs. Three experimental halls are serviced by the accelerator through separate transport channels. The magnet powering system for CEBAF consists of approximately 2000 independent control channels. About 1850 of these channels are low current, trim magnet power supplies. There are 28 higher power supplies used to energize the major bending elements. Over one hundred, 20 amp, active shunts are used to vary current in selected magnets in the major dipole strings. The majority of the magnetic elements are concentrated in the arcs and transport channels. The correction dipoles, quadrupoles and sextupoles are each powered individually be a dedicated trim power supply channel. The arc and extraction channel dipoles are powered in series strings by the high powered supplies, known locally at CEBAF as ``box power supplies``. Arc loads consist of some 30-40 magnets in series. Transport channel, path length control doglegs and septa box power supplies have loads ranging from 1 to 10 magnets. Shunts are installed on virtually all loads where two or more magnets are in series. At this time, 95{percent} of the power supplies are installed and commissioned. In the past twelve months, beginning in May 1994, approximately 1200 trim magnet power supplies have been checked out. During this same period approximately 22 box power supplies and 100 shunts have been made operational. Full operation of the equipment has only been under way since early 1995. While this operation is only just beginning, much has been learned based on the reliability performance seen so far. The remainder of this paper describes the systems mentioned, their reliability problems, the fixes implemented to date, and some plans for the future. 6 refs., 3 tabs.
Date: August 1, 1996
Creator: Merz, W.; Flood, R.; Martin, E. J. & O`Sullivan, M.
Partner: UNT Libraries Government Documents Department

Jefferson Lab, a status report

Description: Thomas Jefferson National Accelerator Facility (Jefferson Lab; formerly known as CEBAF), operates a 4 GeV, 200 {micro}A continuous wave (CW) electron accelerator that re-circulates the beam five times through two superconducting 400 MeV linacs. Electrons can be extracted from any of the five recirculation passes and beam can be simultaneously delivered to the three experimental halls. As the commissioning stage nears completion, the accelerator is becoming a fully operational machine. Experiments in Hall C have been underway since November 1995 with beam powers of over 300 kW at various energies. Hall A has received beam for spectrometer commissioning, while Hall B is expected to receive its first beam in the fall of 1996. Accelerator availability of greater than 70% during physics runs and excellent beam quality have contributed to making Jefferson Lab a world class laboratory for accelerator-based electromagnetic nuclear physics. With the high performance of the superconducting RF cavities, machine upgrades to 6 GeV, and eventually 8 to 10 GeV are now in the planning stages. Operational and commissioning details concerning all aspects of the machine will be discussed.
Date: October 1, 1996
Creator: Dunham, B. M.
Partner: UNT Libraries Government Documents Department

Space-charge-dominated beam dynamics simulations using the massively parallel processors (MPPs) of the Cray T3D

Description: Computer simulations using the multi-particle code PARMELA with a three-dimensional point-by-point space charge algorithm have turned out to be very helpful in supporting injector commissioning and operations at Thomas Jefferson National Accelerator Facility (Jefferson Lab, formerly called CEBAF). However, this algorithm, which defines a typical N{sup 2} problem in CPU time scaling, is very time-consuming when N, the number of macro-particles, is large. Therefore, it is attractive to use massively parallel processors (MPPs) to speed up the simulations. Motivated by this, the authors modified the space charge subroutine for using the MPPs of the Cray T3D. The techniques used to parallelize and optimize the code on the T3D are discussed in this paper. The performance of the code on the T3D is examined in comparison with a Parallel Vector Processing supercomputer of the Cray C90 and an HP 735/15 high-end workstation.
Date: October 1, 1996
Creator: Liu, H.
Partner: UNT Libraries Government Documents Department

Correction of dispersion and the betatron functions in the CEBAF accelerator

Description: During the commissioning of the CEBAF accelerator, correction of dispersion and momentum compaction, and, to a lesser extent, transverse transfer matrices were essential for robust operation. With changing machine conditions, repeated correction was found necessary. To speed the diagnostic process the authors developed a method which allows one to rapidly track the machine optics. The method is based on measuring the propagation of 30 Hz modulated betatron oscillations downstream of a point of perturbation. Compared to the usual methods of dispersion or difference orbit measurement, synchronous detection of the beam displacement, as measured by beam position monitors, offers significantly improved speed and accuracy of the measurements. The beam optics of the accelerator was altered to decrease lattice sensitivity at critical points and to simplify control of the betatron function match. The calculation of the Courant-Snyder invariant from signals of each pair of nearby beam position monitors has allowed one to perform on-line measurement and correction of the lattice properties.
Date: October 1, 1996
Creator: Lebedev, V. A.; Bickley, M.; Schaffner, S.; Zeijts, J. van; Krafft, G. A. & Watson, C.
Partner: UNT Libraries Government Documents Department

Conceptual foundation of the Fokker-Planck approach to space-charge effects

Description: An rms-mismatched beam can evolve rapidly to a configuration of quasiequilibrium under the influence of space-charge forces. As sit evolves, its emittance grows and a diffuse halo forms. The beam`s distribution function accounts for all the complicated dynamics. Unfortunately, the distribution function is difficult to calculate inasmuch as the physics lies at the interface between classical mechanics and thermodynamics. This paper presents the foundation for a statistical theory of the dynamics of nonequilibrium space-charge-dominated beams. Within certain approximations, the theory takes on a Fokker-Planck form. Key questions arise concerning the nature of the dynamical friction and diffusion in the beam`s phase space and of the quasiequilibrium configuration that ensues.
Date: July 1, 1996
Creator: Bohn, C. L.
Partner: UNT Libraries Government Documents Department