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DEVELOPMENT OF AN INSOLUBLE SALT SIMULANT TO SUPPORT ENHANCED CHEMICAL CLEANING TESTS
The closure process for high level waste tanks at the Savannah River Site will require dissolution of the crystallized salts that are currently stored in many of the tanks. The insoluble residue from salt dissolution is planned to be removed by an Enhanced Chemical Cleaning (ECC) process. Development of a chemical cleaning process requires an insoluble salt simulant to support evaluation tests of different cleaning methods. The Process Science and Engineering section of SRNL has been asked to develop an insoluble salt simulant for use in testing potential ECC processes (HLE-TTR-2007-017). An insoluble salt simulant has been developed based upon the residues from salt dissolution of saltcake core samples from Tank 28F. The simulant was developed for use in testing SRS waste tank chemical cleaning methods. Based on the results of the simulant development process, the following observations were developed: (1) A composition based on the presence of 10.35 grams oxalate and 4.68 grams carbonate per 100 grams solids produces a sufficiently insoluble solids simulant. (2) Aluminum observed in the solids remaining from actual waste salt dissolution tests is probably precipitated from sodium aluminate due to the low hydroxide content of the saltcake. (3) In-situ generation of aluminum hydroxide (by …
Date:
May 23, 2008
Creator:
Eibling, R
Object Type:
Report
System:
The UNT Digital Library
Status report on the Small Secure Transportable Autonomous Reactor (SSTAR) /Lead-cooled Fast Reactor (LFR) and supporting research and development.
This report provides an update on development of a pre-conceptual design for the Small Secure Transportable Autonomous Reactor (SSTAR) Lead-Cooled Fast Reactor (LFR) plant concept and supporting research and development activities. SSTAR is a small, 20 MWe (45 MWt), natural circulation, fast reactor plant for international deployment concept incorporating proliferation resistance for deployment in non-fuel cycle states and developing nations, fissile self-sufficiency for efficient utilization of uranium resources, autonomous load following making it suitable for small or immature grid applications, and a high degree of passive safety further supporting deployment in developing nations. In FY 2006, improvements have been made at ANL to the pre-conceptual design of both the reactor system and the energy converter which incorporates a supercritical carbon dioxide Brayton cycle providing higher plant efficiency (44 %) and improved economic competitiveness. The supercritical CO2 Brayton cycle technology is also applicable to Sodium-Cooled Fast Reactors providing the same benefits. One key accomplishment has been the development of a control strategy for automatic control of the supercritical CO2 Brayton cycle in principle enabling autonomous load following over the full power range between nominal and essentially zero power. Under autonomous load following operation, the reactor core power adjusts itself to equal …
Date:
June 23, 2008
Creator:
Sienicki, J. J.; Moisseytsev, A.; Yang, W. S.; Wade, D. C.; Nikiforova, A.; Hanania, P. et al.
Object Type:
Report
System:
The UNT Digital Library
Electron Bypass Line (EBL) Design: Electrons to A-line bypassing LCLS
Forty one years ago, September 20, 1966, the first beam entered End Station A, passed on through, and was terminated in Beam Dump East. This beam had an energy of 18.4 GeV, a record for the time. Since then, the SLAC ESA has been a mainstay facility for many high-energy physics and test beam experiments involving countless hours of data taking. Heretofore, it was assumed that with the completion and commissioning of the LCLS facility, beams from the main injector would no longer be available to this well equipped experimental facility. Fortunately, it has become clear that a bypass beamline design calling for modest modifications and using existing, soon to be surplus, components will enable continued utilization of this important facility.
Date:
January 23, 2008
Creator:
Fieguth, T. & Arnold, R.
Object Type:
Report
System:
The UNT Digital Library
The MERIT(nTOF-11) High Intensity Liquid Mercury Target Experiment at the CERN PS
The MERIT(nTOF-11) experiment is a proof-of-principle test of a target system for a high power proton beam to be used as front-end for a neutrino factory or a muon collider. The experiment took data in autumn 2007 with the fast-extracted beam from the CERN Proton Synchrotron (PS) to a maximum intensity of 30 x 10{sup 12} per pulse. The target system, based on a free mercury jet, is capable of intercepting a 4-MW proton beam inside a 15-T magnetic field required to capture the low energy secondary pions as the source for intense muon beams. Particle detectors installed around the target setup measure the secondary particle flux out of the target and can probe cavitation effects in the mercury jet when excited by an intense proton beam.Preliminary results of the data analysis will be presented here.
Date:
June 23, 2008
Creator:
Ethymiopoulos, I.; Fabich, A.; Palm, M.; Lettry, J.; Haug, F.; Pernegger, H. et al.
Object Type:
Article
System:
The UNT Digital Library
Outline for an experiment on multi-turn patterns of a crystal collimation system.
None
Date:
June 23, 2008
Creator:
Robert-Demolaize,G.; Drees, A.; Fliller, R. & Peggs, S.
Object Type:
Article
System:
The UNT Digital Library
p-Carbon CNI polarimetry in the AGS and RHIC.
Proton polarization measurements in the AGS (Alternate Gradient Synchrotron) and RHIC (Relativistic Heavy Ion Collider) are based on proton-carbon(pC) and proton-proton elastic scattering in the Coulomb Nuclear Interference (CNI) region. The CNI polarimeters are the essential tools for polarized proton acceleration setup and operation. High intensity recoil nuclei from the scattering of the circulating proton beam in the thin carbon target is efficiently utilized in the silicon strip detectors and data acquisition system, which is capable to analyze the event rate up to a few millions/second. This makes it possible for the fast, practically non-destructive polarization measurements. The polarization measurement on the beam energy ramp was implemented in AGS and RHIC, providing locations of polarization losses. Polarimeter operation in the scanning mode also gives polarization profile and beam profile (including bunch by bunch values for the later one). This paper summarizes the recent modifications. Results of polarization measurements are also discussed.
Date:
June 23, 2008
Creator:
Huang, H.; Alekseev, I.; Bazilevsky, A.; Bravar, A.; Bunce, G.; Dhawan, S. et al.
Object Type:
Article
System:
The UNT Digital Library
Search for B to rho/omega gamma decays at BaBar
The authors present the results of the search for the decays B{sup 0/{+-}} {yields} {rho}{sup 0/{+-}}{gamma} (previously observed) and B{sup 0} {yields} {omega}{gamma} (for which currently only an upper limit exists). Together with B {yields} K*{gamma} decays, B {yields} ({rho}/{omega}){gamma} allow us to measure the ratio of CKM-matrix elements |V{sub td}/V{sub ts}|. The analysis is based on the full BABAR dataset of 424.35 fb{sup -1} corresponding to 465 million B{bar B} pairs, and makes heavy use of multivariate classification techniques based on decision trees. They find {Beta}(B{sup {+-}} {yields} {rho}{sup {+-}}{gamma}) = (1.20{sub -0.38}{sup +0.42} {+-} 0.20) x 10{sup -6}, {Beta}(B{sup 0} {yields} {rho}{sup 0}{gamma}) = (0.95{sub -0.21}{sup +0.23} {+-} 0.06) x 10{sup -6}, {Beta}(B{sup 0} {yields} {omega}{gamma}) = (0.51{sub -0.24}{sup +0.27} {+-} 0.10) x 10{sup -6}, where the first error is statistical and the second is systematic. They do not observe a statistically significant signal in the latter channel and set an upper limit at {Beta}(B{sup 0} {yields} {omega}{gamma}) < 0.9 x 10{sup -6} (90% C.L.). They also measure the isospin and SU(3){sub F} violating quantities {Lambda}(B{sup +} {yields} {rho}{sup +}{gamma})/2{Lambda}(B{sup 0} {yields} {rho}{sup 0}{gamma})-1 = -0.43{sub -0.22}{sup +0.25} {+-} 0.10 and {Lambda}(B{sup 0} {yields} {omega}{gamma})/{Lambda}(B{sup 0} {yields} {rho}{sup …
Date:
September 23, 2008
Creator:
Piatenko, Timofei & /SLAC, /Caltech
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Analysis of intensity instability threshold at transition in RHIC.
The beam intensity of ion beams in RHIC is limited by a fast transverse instability at transition, driven by the machine impedance and electron clouds. For gold and deuteron beams we analyze the dependence of the instability threshold on beam and machine parameters from recent operational data and dedicated experiments. We fit the machine impedance to the experimental data.
Date:
June 23, 2008
Creator:
Fischer, W.; Blaskiewicz, M.; Cameron, P.; Montag, C. & Ptitsyn, V.
Object Type:
Article
System:
The UNT Digital Library
ARE660 Wind Generator: Low Wind Speed Technology for Small Turbine Development
This project is for the design of a wind turbine that can generate most or all of the net energy required for homes and small businesses in moderately windy areas. The purpose is to expand the current market for residential wind generators by providing cost effective power in a lower wind regime than current technology has made available, as well as reduce noise and improve reliability and safety. Robert W. Preus’ experience designing and/or maintaining residential wind generators of many configurations helped identify the need for an improved experience of safety for the consumer. Current small wind products have unreliable or no method of stopping the wind generator in fault or high wind conditions. Consumers and their neighbors do not want to hear their wind generators. In addition, with current technology, only sites with unusually high wind speeds provide payback times that are acceptable for the on-grid user. Abundant Renewable Energy’s (ARE) basic original concept for the ARE660 was a combination of a stall controlled variable speed small wind generator and automatic fail safe furling for shutdown. The stall control for a small wind generator is not novel, but has not been developed for a variable speed application with a …
Date:
April 23, 2008
Creator:
Preus, Robert W. & Bennett, Keith
Object Type:
Report
System:
The UNT Digital Library
A FOUR-DIMENSIONAL VLASOV SOLVER FOR MICROBUNCHING INSTABILITY INTHE INJECTION SYSTEM FOR X-RAY FELS
The micro-bunching instability (MBI) is seeded by small charge-density fluctuations in the electron bunches, and is successively amplified by the combined effect of space charge and coherent synchrotron radiation, as the beam travels through magnetic compressors. The quantitative understanding of this effect demands for accurate numerical simulations. Here we report on the progress of an upgrading of a 2D Vlasov solver code toward a 4D grid-based Vlasov solver, including also the transversedynamics. The goal is to provide an accurate characterization of the MBI seeded by random noise present in the bunch distribution. We also comment on the advantages of our procedure with respect to other approaches, e.g. macroparticle simulations.
Date:
June 23, 2008
Creator:
Venturini, Marco; Migliorati, Mauro; Schiavi, Angelo; Dattoli, Giuseppe & Venturini, Marco
Object Type:
Article
System:
The UNT Digital Library
MATRIX 2 RESULTS OF THE FY07 ENHANCED DOE HIGH-LEVEL WASTE MELTER THROUGHPUT STUDIES AT SRNL
High-level waste (HLW) throughput (i.e., the amount of waste processed per unit time) is a function of two critical parameters: waste loading (WL) and melt rate. For the Waste Treatment and Immobilization Plant (WTP) at the Hanford Site and the Defense Waste Processing Facility (DWPF) at the Savannah River Site (SRS), increasing HLW throughput would significantly reduce the overall mission life cycle costs for the Department of Energy (DOE). The objective of this study was to generate supplemental validation data that could be used to determine the applicability of the current liquidus temperature (TL) model to expanded DWPF glass composition regions of interest based on higher WLs. Two specific flowsheets were used in this study to provide such insight: (1) Higher WL glasses (45 and 50%) based on future sludge batches that have (and have not) undergone the Al-dissolution process. (2) Coupled operations supported by the Salt Waste Processing Facility (SWPF), which increase the TiO{sub 2} concentration in glass to greater than 2 wt%. Glasses were also selected to address technical issues associated with Al{sub 2}O{sub 3} solubility, nepheline formation, and homogeneity issues for coupled operations. A test matrix of 28 glass compositions was developed to provide insight into these …
Date:
October 23, 2008
Creator:
Raszewski, F; Tommy Edwards, T & David Peeler, D
Object Type:
Report
System:
The UNT Digital Library
Feedback damper system for quadrupole oscillations after transition at RHIC.
The heavy ion beam at RHIC undergoes strong quadrupole oscillations just after it crosses transition, which leads to an increase in bunch length making rebucketing less effective. A feedback system was built to damp these quadrupole oscillations and in this paper the characteristics of the system and the results obtained are presented and discussed.
Date:
June 23, 2008
Creator:
Abreu, N.; Blaskiewicz, M.; Brennan, J. M. & Schultheiss, C.
Object Type:
Article
System:
The UNT Digital Library
Algorithm for Unfolding Current from Faraday Rotation Measurement
Various methods are described to translate Faraday rotation measurements into a useful representation of the dynamic current under investigation[1]. For some experiments, simply counting the “fringes” up to the turnaround point in the recorded Faraday rotation signal is sufficient in determining the peak current within some allowable fringe uncertainty. For many other experiments, a higher demand for unfolding the entire dynamic current profile is required. In such cases, investigators often rely extensively on user interaction on the Faraday rotation data by visually observing the data and making logical decisions on what appears to be turnaround points and/or inflections in the signal. After determining extrema, inflection points, and locations, a piece-wise, ΔI/Δt, representation of the current may be revealed with the proviso of having a reliable Verdet constant of the Faraday fiber or medium and time location for each occurring fringe. In this paper, a unique software program is reported which automatically decodes the Faraday rotation signal into a time-dependent current representation. System parameters such as the Faraday fiber’s Verdet constant and number of loops in the sensor are the only user-interface inputs. The central aspect of the algorithm utilizes a short-time Fourier transform (STFT) which reveals much of the Faraday …
Date:
May 23, 2008
Creator:
Mitchell, Stephen E.
Object Type:
Article
System:
The UNT Digital Library
Insertion Devices for NSLS-II Baseline and Future
NSLS-II is going to employ Damping Wigglers (DWs) not only for emittance reduction but also as broad band hard X-ray source. In-Vacuum Undulators (IVUs) with the minimum RMS phase error (< 2 degree) and possible cryo-capability are planned for X-ray planar device. Elliptically Polarized Undulators (EPUs) are envisioned for polarization controls. Due to the lack of hard X-ray flux from weak dipole magnet field (0.4 Tesla), three pole wigglers (3PWs) of the peak field over 1 Tesla will be mainly used by NSLS bending magnet beam line users. Magnetic designs and kick maps for dynamic aperture surveys were created using the latest version of Radia [1] for Mathematica 6 which we supported the development. There are other devices planned for the later stage of the project, such as quasi-periodic EPU, superconducting wiggler/undulator, and Cryo-Permanent Magnet Undulator (CPMU) with Praseodymium Iron Boron (PrFeB) magnets and textured Dysprosium poles. For R&D, Hybrid PrFeB arrays were planned to be assembled and field-measured at room temperature, liquid nitrogen and liquid helium temperature using our vertical test facility. We have also developed a specialized power supply for pulsed wire measurement.
Date:
June 23, 2008
Creator:
Tanabe,T.
Object Type:
Article
System:
The UNT Digital Library
Achieving Stability Requirements for Nanoprobe and Long Beam Lines at NSLS II. A Comprehensive Study
Driven by beam stability requirements at the NSLS II synchrotron, such that the desired small beam sizes and high brightness are both realized and stable, a comprehensive study has been launched seeking to provide assurances that stability at the nanometer level at critical x-ray beam-lines, is achievable, given the natural and cultural vibration environment at the selected site. The study consists of (a) an extensive investigation of the site to evaluate the existing ground vibration, in terms of amplitude, frequency content and coherence, and (b) of a numerical study of wave propagation and interaction with the infrastructure of the sensitive lines. The paper presents results from both aspects of the study.
Date:
June 23, 2008
Creator:
Simos,N.; Fallier, M.; Hill, J.; Berman, L.; Evans-Lutterodt, K. & Broadbent, A.
Object Type:
Article
System:
The UNT Digital Library
Hybrid Paper/Electronic Archival Collecting, Processing, and Reference: A View from SLAC
Real-time archiving of mixed paper and digital collections presents challenges not encountered in the primarily paper environment. A few recent examples from the archives of the Stanford Linear Accelerator Center highlight obstacles encountered, and attempted and contemplated solutions.
Date:
May 23, 2008
Creator:
Deken, Jean M.
Object Type:
Article
System:
The UNT Digital Library
Intense Ion Beam for Warm Dense Matter Physics
The Neutralized Drift Compression Experiment (NDCX) at Lawrence Berkeley National Laboratory is exploring the physical limits of compression and focusing of ion beams for heating material to warm dense matter (WDM) and fusion ignition conditions. The NDCX is a beam transport experiment with several components at a scale comparable to an inertial fusion energy driver. The NDCX is an accelerator which consists of a low-emittance ion source, high-current injector, solenoid matching section, induction bunching module, beam neutralization section, and final focusing system. The principal objectives of the experiment are to control the beam envelope, demonstrate effective neutralization of the beam space-charge, control the velocity tilt on the beam, and understand defocusing effects, field imperfections, and limitations on peak intensity such as emittance and aberrations. Target heating experiments with space-charge dominated ion beams require simultaneous longitudinal bunching and transverse focusing. A four-solenoid lattice is used to tune the beam envelope to the necessary focusing conditions before entering the induction bunching module. The induction bunching module provides a head-to-tail velocity ramp necessary to achieve peak axial compression at the desired focal plane. Downstream of the induction gap a plasma column neutralizes the beam space charge so only emittance limits the focused beam …
Date:
May 23, 2008
Creator:
Coleman, Joshua Eugene
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Measurements of the Propagation of EM Waves through the Vacuum Chamber of the PEP-II Low Energy Ring for Beam Diagnostics
We present the results of our measurements of the electron cloud density in the PEP-II low energy ring (LER) by propagating a TE wave into the beam pipe. By connecting a signal generator to a beam position monitor button we can excite a signal above the vacuum chamber cut-off frequency and measure its propagation through the beam pipe with a spectrum analyzer connected to another button about 50 meters away. The measurement can be performed with different beam conditions and also at different settings of the solenoids used to reduce the build up of electrons. The presence of a modulation in the TE wave transmission, synchronous with the beam revolution frequency, which appear to increase in depth when the solenoids are switched off, seem to be directly correlated to the electron cloud density in the region between the two BPM's. In this paper we present and discuss the measurements taken in the Interaction Region 12 straight of the LER during 2006 and the first part of 2007.
Date:
January 23, 2008
Creator:
Byrd, John Michael; De Santis, S. & Pivi, MTF
Object Type:
Article
System:
The UNT Digital Library
Physical limits for high ion charge states in pulsed discharges in vacuum
Short-pulse, high-current discharges in vacuum were investigated with the goal to maximize the ion charge state number. In a direct extension of previous work [Appl. Phys. Lett. 92, 041502 (2008)], the role of pulse length, rate of current rise, and current amplitude was studied. For all experimental conditions, the usable (extractable) mean ion charge state could not be pushed beyond 7+. Instead, a maximum of the mean ion charge state (about 6+ to 7+ for most cathode materials) was found for a power of 2-3 MW dissipated in the discharge gap. The maximum is the result of two opposing processes that occur when the power is increased: (i) the formation of higher ion charge states, and (ii) a greater production of neutrals (both metal and non-metal), which reduces the charge state via charge exchange collisions.
Date:
December 23, 2008
Creator:
Yushkov, Georgy & Anders, Andre
Object Type:
Article
System:
The UNT Digital Library
Temperature effect on low-k dielectric thin films studied by ERDA
Low-k dielectric materials are becoming increasingly interesting as alternative to SiO2 with device geometries shrinking beyond the 65 nm technology node. At elevated temperatures hydrogen migration becomes an important degradation mechanism for conductivity breakdown in semiconductor devices. The possibility of hydrogen release during the fabrication process is, therefore, of great interest in the understanding of device reliability. In this study, various low-k dielectric films were subjected to thermal annealing at temperatures that are generally used for device fabrication. Elastic recoil detection analysis (ERDA) was used to investigate compositional changes and hydrogen redistribution in thin films of plasma-enhanced tetraethylortho-silicate (PETEOS), phosphorus doped silicon glass (PSG), silicon nitride (SiN) and silicon oxynitride (SiON). Except for an initial hydrogen release from the surface region in films of PETEOS and PSG, the results indicate that the elemental composition of the films was stable for at least 2 hours at 450◦C.
Date:
September 23, 2008
Creator:
Jensen, Jens; Possnert, Göran & Zhang, Yanwen
Object Type:
Article
System:
The UNT Digital Library
An Instrument Design for the Accurate Determination of the Electron Beam Location in the Linac Coherent Light Source Undulator
The Linac Coherent Light Source (LCLS), currently under design, requires accurate alignment between the electron beam and each undulator's magnetic centerline. A beam finder wire (BFW) instrument has been developed to provide beam location information that is used to move the undulators to their appropriate positions. A BFW instrument is mounted at each of the 33 magnets in the undulator section. Beam detection is achieved by electrons impacting two carbon fiber wires and then sensing the downstream radiation. The wires are mounted vertically and horizontally on a wire card similar to that of a traditional wire scanner instrument. The development of the BFW presents several design challenges due to the need for high accuracy of the wires locations and the need for removal of the wires during actual operation of the LCLS (30 microns repeatability is required for the wire locations). In this paper, we present the technical specification, design criteria, mechanical design, and results from prototype tests for the BFW.
Date:
January 23, 2008
Creator:
Bailey, J. L.; Capatina, D.; Morgan, J. W. & Nuhn, H. D.
Object Type:
Article
System:
The UNT Digital Library
Application of Entry-Time Processes in Asset Management for Nuclear Power Plants (Final Report)
A mathematical model of entry-time processes was developed, and a computational method for solving that model was verified. This methodology was demonstrated via application to a succession of increasingly more complex subsystems of nuclear power plants. The effort culminated in the application to main generators that constituted the PhD dissertation of Shuwen (“Eric”) Wang. Dr. Wang is now employed by ABS Consulting, in Anaheim, CA. ABS is a principal provider to the nuclear industry of technical services related to reliability and safety.
Date:
January 23, 2008
Creator:
Nelson, Paul
Object Type:
Report
System:
The UNT Digital Library
Remaining Sites Verification Package for the 100-F-44:4, Discovery Pipeline in Silica Gel Pit, Waste Site Reclassification Form 2008-030
The 100-F-44:4, Discovery Pipeline in Silica Gel Pit subsite is located in the 100-FR-1 Operable Unit of the Hanford Site, near the location of the former 110-F Gas Storage Tanks structure. The 100-F-44:4 subsite is a steel pipe discovered October 17, 2004, during trenching to locate the 118-F-4 Silica Gel Pit. Based on visual inspection and confirmatory investigation sampling data, the 100-F-44:4 subsite is a piece of non-hazardous electrical conduit debris. The 100-F-44:4 subsite supports unrestricted future use of shallow zone soil and is protective of groundwater and the Columbia River. No residual contamination exists within the deep zone. Therefore, no deep zone institutional controls are required.
Date:
September 23, 2008
Creator:
Capron, J. M.
Object Type:
Report
System:
The UNT Digital Library
Ground Motion Studies at NSLS II
In this study, an array of vibration measurements at the undisturbed NSLS II site has been performed in order to establish the 'green-field' vibration environment and its spectral characteristics. The interaction of the green-field vibration environment with the NSLS II accelerator structure and the quantification of the storage ring vibration, both in terms of amplitude and spectral content have been assessed through a state-of-the-art wave propagation and scattering analysis. This paper focuses on the wave propagation and scattering aspect as well as on the filtering effects of accelerator structural parameters.
Date:
June 23, 2008
Creator:
Simos,N.; Fallier, M. & Amick, H.
Object Type:
Article
System:
The UNT Digital Library