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Annual Coded-Wire Tag Program : Washington : Missing Production Groups Annual Report for 2000.

Description: The Bonneville Power Administration (BPA) funds the 'Annual Coded-wire Tag Program - Missing Production Groups for Columbia River Hatcheries' project. The Washington Department of Fish and Wildlife (WDFW), Oregon Department of Fish and Wildlife (ODFW) and the United States Fish and Wildlife Service (USFWS) all operate salmon and steelhead rearing programs in the Columbia River basin. The intent of the funding is to coded-wire tag at least one production group of each species at each Columbia Basin hatchery to provide a holistic assessment of survival and catch distribution over time and to meet various measures of the Northwest Power Planning Council's (NWPPC) Fish and Wildlife Program. The WDFW project has three main objectives: (1) coded-wire tag at least one production group of each species at each Columbia Basin hatchery to enable evaluation of survival and catch distribution over time, (2) recover coded-wire tags from the snouts of fish tagged under objective 1 and estimate survival, contribution, and stray rates for each group, and (3) report the findings under objective 2 for all broods of chinook, and coho released from WDFW Columbia Basin hatcheries. Objective 1 for FY-00 was met with few modifications to the original FY-00 proposal. Under Objective 2, snouts containing coded-wire tags that were recovered during FY-00 were decoded. Under Objective 3, this report summarizes available recovery information through 2000 and includes detailed information for brood years 1989 to 1994 for chinook and 1995 to 1997 for coho.
Date: February 1, 2002
Creator: Mills, Robin D.
Partner: UNT Libraries Government Documents Department

Top quark physics

Description: While the top quark was discovered in 1995 at the Fermilab Tevatron, a decade later they still have very little information about the top. As the heaviest particle yet discovered, the top quark is interesting in and of itself, but some speculate that it may play a special role in physics beyond the Standard Model. With Run 2 of the Tevatron well underway, they have the opportunity to study top quark properties with much better sensitivity, and to test whether top quarks behave as predicted by current theories. This article focuses on the basics of top quark physics at the Tevatron, highlighting only a sample of the many recent measurements, as new results are being released monthly, and constantly changing the landscape of our knowledge of top.
Date: October 1, 2005
Creator: Erbacher, Robin D. & /UC, Davis
Partner: UNT Libraries Government Documents Department

Effects of Goal Setting, E-mail Feedback and Graphic Feedback on the Productivity of Public School Attendance Clerks

Description: A package intervention, consisting of daily-adjusted goal setting, e-mail feedback, and graphic feedback, was used in a public school attendance office to increase the efficiency with which 3 attendance clerks documented student attendance. During the intervention phase, the attendance secretary set a daily goal for each attendance clerk. This goal was a percentage of student absences to be coded and entered in the school computer program. After establishing a daily goal, the attendance secretary provided daily feedback, in the form of a written e-mail response and graphed feedback to each clerk. If the subjects had attained their daily goal, the attendance secretary also delivered a praise statement along with the e-mail feedback. Results indicated that the intervention package was ineffective in producing change in the attendance clerks' absence coding behavior.
Date: August 2000
Creator: Rexroat, Robin D.
Partner: UNT Libraries

Compton scattering in the ALS booster

Description: Femtosecond x-ray pulses may be generated by 90{degrees} Compton side scattering of a short visible laser beam by a well-focused relativistic electron beam. A proof-of-principle experiment is underway using the ALS linac. From this experiment an x-ray pulse of 10{sup 5} photons with a duration of 230 fs in a bandwidth of 10% at 10 Hz is expected. In this paper we explore using the ALS booster instead to increase the average x-ray flux. To generate the small beam size we plan to radiation damp electrons by accelerating them to 600 MeV and decelerate quickly to 50 MeV before intra-beam scattering can increase the beam size. We can achieve a vertical emittance of <5 {times} 10{sup {minus}9} m-rad. With a small modification of the booster lattice it is possible to focus the beam to a vertical beta function of {Beta}{sub y}* = 10 cm. By reflecting the incident laser pulse many times we expect to be able to obtain an increase of the average x-ray flux.
Date: April 1, 1995
Creator: Robin, D.; Kim, C. & Sessler, A.
Partner: UNT Libraries Government Documents Department

Momentum Aperture of the Advanced Light Source

Description: This paper shows measurements of the momentum aperture of the Advanced Light Source (ALS) based on Touschek lifetime measurements. The measured data is compared with tracking simulations and a simple model for the apertures will help to explain the observed effects.
Date: August 1, 1998
Creator: Decking, W. & Robin, D.
Partner: UNT Libraries Government Documents Department

Impact of superbends at the ALS

Description: To satisfy a demand for high energy, high brightness x-ray sources at the Advanced Light Source (ALS), a plan is in place to replace three 1.3 Tesla normal conducting bending magnets with three 5 Tesla superconducting magnets (superbends) in the year 2001. In this paper they discuss the impact of the superbends on the ALS beam parameters and particle dynamics. In particular they show the effect on the emittance, energy spread, and lifetime. They find that by adjusting the dispersion to be positive in the straight section they are able to largely restore the horizontal emittance. The vertical emittance can be adjusted independently to control the lifetime. The particle dynamics are investigated through particle tracking with a frequency analysis postprocessor. They find that by placing the three superbends symmetrically around the ring there is ample dynamic aperture for injection and lifetime.
Date: March 19, 1999
Creator: Nishimura, H. & Robin, D.
Partner: UNT Libraries Government Documents Department

Automated beam based alignment of the ALS quadrupoles

Description: Knowing the electrical offset of the storage ring beam position monitors (BPM) to an adjacent quadrupole magnetic center is important in order to correct the orbit in the ring. The authors describe a simple, fast and reliable technique to measure the BPM electrical centers relative to the quadrupole magnetic centers. By varying individual quadrupole magnets and observing the effects on the orbit they were able to measure the BPM offsets in half the horizontal and vertical BPMs (48) in the ALS. These offsets were measured to an accuracy of better than 50{mu}m. The technique is completely automated and takes less than 3 hours for the whole ring.
Date: April 1995
Creator: Portmann, G.; Robin, D. & Schachinger, L.
Partner: UNT Libraries Government Documents Department

Application of frequency map analysis to the ALS

Description: Frequency map analysis is a numerical method based on Fourier techniques which provides a clear representation of the global dynamics of many multi-dimensional systems, and which is particularly useful for systems of 3 degrees of freedom and more. The frequency dependence with time also allows refined estimates of the diffusion of the orbits. Here are presented the theoretical foundation of the method, and some applications to the Advanced Light Source, demonstrating how frequency map analysis can be used to understand the limits of the dynamic aperture under various lattice conditions and predict more favorable working points.
Date: January 1, 1996
Creator: Laskar, J. & Robin, D.
Partner: UNT Libraries Government Documents Department

Experimental results on low alpha electron-storage rings

Description: The authors report on experiments performed in two synchrotron light sources, UVSOR and Super-ACO, where the momentum compaction factor is reduced in order to reduce the bunch length. By controlling the second-order momentum compaction factor, UVSOR and Super-ACO have managed to reduce the first-order momentum compaction factor by 100. At low current the resulting bunch lengths are less than 10 ps, a factor of 10 smaller than normal. Measurements of current dependent bunch lengthening in UVSOR are presented and the cause of the bunch lengthening is determined to be potential-well distortion. The authors also show that by operating with a negative momentum compaction factor, SuperACO has achieved shorter bunch lengthening and higher peak currents than at positive momentum compaction.
Date: September 1, 1995
Creator: Robin, D.; Hama, H. & Nadji, A.
Partner: UNT Libraries Government Documents Department

A New Class of Solvents for TRU Dissolution and Separation: Ionic Liquids

Description: Through the current EMSP funding, solvent extraction technologies based on liquid-liquid partitioning of TRU to an Ionic Liquid phase containing conventional complexants has been shown to be viable. The growing understanding of the role that the different components of an ionic liquid can have on the partitioning mechanism, and on the nature of the subsequent dissolved species indicates strongly that ionic liquids are not necessarily direct replacements for volatile or otherwise hazardous organic solvents. Separations and partitioning can be exceptionally complex with competing solvent extraction, cation, anion and sacrificial ion exchange mechanisms are all important, depending on the selection of components for formation of the ionic liquid phase, and that control of these competing mechanisms can be utilized to provide new, alternative separations schemes.
Date: December 31, 2004
Creator: Rogers, Robin D.
Partner: UNT Libraries Government Documents Department

Novel Fission-Product Separation based on Room-Temperature Ionic Liquids

Description: U.S. DOE's underground storage tanks at Hanford, SRS, and INEEL contain liquid wastes with high concentrations of radioactive cesium-137 and strontium-90. Because the primary chemical components of alkaline supernatants are sodium nitrate and sodium hydroxide, the majority of this could be disposed of as low level waste if radioactive cesium-137 and strontium- 90 could be selectively removed. The underlying goal of this project was to investigate the application of ionic liquids as novel solvents for new solvent extraction processes for separation of cesium-137 and strontium-90 from tank wastes. Ionic liquids are a distinct sub-set of liquids, comprising only of cations and anions they are proving to be increasingly interesting fluids for application in systems from electrochemistry to energetic materials, and are also rapidly establishing their promise as viable media for synthesis and separations operations. Properties including low melting points, electrochemical conductivity, wide liquid ranges, lack of vapor-pressure, and chemical tunability have encouraged researchers to explore the uses of ILs in place of volatile organic solvents. The most promising current developments arise from control of the unique combinations of chemical and physical properties characteristic of ionic liquids.
Date: December 31, 2004
Creator: Rogers, Robin D.
Partner: UNT Libraries Government Documents Department

Dynamic Aperture Measurements at the Advanced Light Source

Description: A large dynamic aperture for a storage ring is of importance for long lifetimes and a high injection efficiency. Measurements of the dynamic aperture of the third generation synchrotron light source Advanced Light Source (ALS) using beam excitation with kicker magnets are presented. The experiments were done for various accelerator conditions, allowing us to investigate the influence of different working points, chromaticities, insertion devices, etc.. The results are compared both with tracking calculations and a simple model for the dynamic aperture yielding good agreements. This gives us confidence in the predictability of the nonlinear accelerator model. This is especially important for future ALS upgrades as well as new storage ring designs.
Date: March 12, 1999
Creator: Decking, W. & Robin, D.
Partner: UNT Libraries Government Documents Department

CDF at the Tevatron collider in Run 2

Description: Run 2 of the Tevatron began in early 2001 after extensive upgrades to both the machine and the CDF and D0 detectors. For CDF, new tracking detectors, increased muon coverage, state-of-the-art front end electronics, pipelined triggering, and a complete overhaul of the DAQ have made it a very powerful tool to explore physics of all kinds. The status of CDF in Run 2 is presented, along with a first glimpse of CDF data.
Date: April 3, 2002
Creator: Erbacher, Robin D.
Partner: UNT Libraries Government Documents Department

A Parameterization Invariant Approach to the Statistical Estimation of the CKM Phase alpha

Description: In contrast to previous analyses, we demonstrate a Bayesian approach to the estimation of the CKM phase {alpha} that is invariant to parameterization. We also show that in addition to computing the marginal posterior in a Bayesian manner, the distribution must also be interpreted from a subjective Bayesian viewpoint. Doing so gives a very natural interpretation to the distribution. We also comment on the effect of removing information about {beta}{sup 00}.
Date: April 14, 2008
Creator: Morris, Robin D.; /RIACS, Mtn. View; Cohen-Tanugi, Johann & /SLAC
Partner: UNT Libraries Government Documents Department

Proceedings of the 25th Rare Earth Research Conference, June 22-26, Tuscaloosa, Alabama, USA Journal of Alloys and Compounds 2009, Vol. 488, Iss. 2, pp 491-656

Description: The program of the 25th Rare Earth Research Conference (RERC08) integrated basic and applied multidisciplinary research centered on the f-elements. Leading science was featured in the form of invited oral presentations and contributed posters on topics in f-element chemistry, physics, and material, earth, environmental, and biological sciences. The conference was held in Shelby Hall, located on The University of Alabama?s Tuscaloosa, AL campus. The final program and list of attendees is available at URL http://bama.ua.edu/~rdrogers/RERC08/.
Date: December 4, 2009
Creator: Rogers, Robin D.
Partner: UNT Libraries Government Documents Department

Project Plan Remote Target Fabrication Refurbishment Project

Description: In early FY2009, the DOE Office of Science - Nuclear Physics Program reinstated a program for continued production of {sup 252}Cf and other transcurium isotopes at the Radiochemical Engineering Development Center (REDC) at Oak Ridge National Laboratory (ORNL). The FY2009 major elements of the workscope are as follows: (1) Recovery and processing of seven transuranium element targets undergoing irradiation at the High Flux Isotope Reactor (HFIR) at ORNL; (2) Development of a plan to manufacture new targets for irradiation beginning in early- to mid-FY10 to supply irradiated targets for processing Campaign 75 (TRU75); and (3) Refurbishment of the target manufacturing equipment to allow new target manufacture in early FY10 The {sup 252}Cf product from processing Campaign 74 (recently processed and currently shipping to customers) is expected to supply the domestic demands for a period of approximately two years. Therefore it is essential that new targets be introduced for irradiation by the second quarter of FY10 (HFIR cycle 427) to maintain supply of {sup 252}Cf; the average irradiation period is {approx}10 HFIR cycles, requiring about 1.5 calendar years. The strategy for continued production of {sup 252}Cf depends upon repairing and refurbishing the existing pellet and target fabrication equipment for one additional target production campaign. This equipment dates from the mid-1960s to the late 1980s, and during the last target fabrication campaign in 2005- 2006, a number of component failures and operations difficulties were encountered. It is expected that following the target fabrication and acceptance testing of the targets that will supply material for processing Campaign 75 a comprehensive upgrade and replacement of the remote hot-cell equipment will be required prior to subsequent campaigns. Such a major refit could start in early FY 2011 and would take about 2 years to complete. Scope and cost estimates for the repairs described herein were ...
Date: August 1, 2009
Creator: Bell, Gary L & Taylor, Robin D
Partner: UNT Libraries Government Documents Department

Low alpha experiments at the ALS

Description: The authors present a modified, low alpha lattice for the Advanced Light Source where the quadrupole field strengths have been detuned to allow the momentum compaction factor to be varied smoothly from positive to negative values. With this low alpha lattice the authors decrease the momentum compaction factor by a factor of 5 to 0.0003 over normal operation resulting in a measured bunch length reduction of 2. They also measure the size the second order momentum compaction factor as well as store beam in a negative momentum compaction lattice. Streak camera measurements at positive and negative momentum compaction operation show longitudinal beam profile distributions that are in agreement with simulations by Fang et al.
Date: August 1, 1995
Creator: Robin, D.; Alvis, R.; Jackson, A.; Holtzapple, R. & Podobedov, B.
Partner: UNT Libraries Government Documents Department

Understanding the nonlinear beam dynamics of the Advanced Light Source

Description: Frequency map analysis is used to study the single particle transverse beam dynamics in ALS. The maps, which provide details about the diffusion of orbits and limits on long term stability, are generated by a postprocessor attached to a tracking code. This paper describes the method and shows how the map is changed when the 12- fold symmetry of the linear lattice is perturbed by including measured magnetic field imperfections. Also the long term stability of orbits that reside in regions of large diffusion is studied.
Date: September 18, 1996
Creator: Robin, D. & Laskar, J.
Partner: UNT Libraries Government Documents Department

Debugging real accelerators

Description: Particle losses and emittance growth in the injection process can result form mismatched injected beams arising from quadrupole errors in the ring and injection line. We describe a method, based on carefully analyzing the BPM-corrector response matrix, which allows the accurate determination of quadrupole errors and, at the same time, determines BPM and corrector calibration errors as well as the BPM resolution. Results from SPEAR, NSLS, ALS, and CELSIUS will be briefly described.
Date: December 1, 1996
Creator: Corbett, W.J.; Robin, D.; Safranek, J. & Ziemann, V.
Partner: UNT Libraries Government Documents Department

Global beta-beating compensation of the ALS W16 wiggler

Description: The W16 wiggler is the first wiggler and highest field insertion device to be installed in the ALS storage ring. When the gaps of the W16 wiggler are closed, the vertical tune increases by 0.065 and the vertical beta function is distorted by up to {+-}37%. There are 48 quadrupoles in the ring whose fields can be adjusted individually to restore the tunes and partially compensate the beta-beating. In order to adjust the quadrupole field strengths to accurately compensate the focusing, it is necessary to have a method to precisely determine the beta-beating. In this paper we compare measurements of the induced beta-beating using two methods: measuring the tune dependence on quadrupole field strength and fitting a lattice model with measured response matrices. The fitted model also allows us to predict quadrupole field strengths that will best compensate the beta beating. These quadrupole field strengths are then applied and the resultant beta-beating is measured.
Date: May 1, 1997
Creator: Robin, D.; Decking, W. & Nishimura, H.
Partner: UNT Libraries Government Documents Department

Model calibration and symmetry restoration of the advanced light source

Description: The symmetry of the ALS magnetic lattice is crucial in suppressing nonlinear structural resonances. Breaking the symmetry of the lattice can lead to a reduction in the dynamic aperture. The degree of symmetry breaking can be determined by fitting a magnetic lattice model to the measured orbit response matrix. This reveals a large beating of the vertical beta-function caused mainly by gradient errors in the QD quadrupole magnets. When the quadrupole field strengths are adjusted to compensate for the gradient errors, the symmetry of the lattice is restored. The new lattice has a larger dynamic aperture and an improved injection efficiency.
Date: June 10, 1996
Creator: Robin, D.; Portmann, G.; Nishimura, H. & Safranek, J.
Partner: UNT Libraries Government Documents Department