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The role of SNM portal monitoring in the Russian MPC & A program

Description: Controlling the movement of nuclear materials is still the most effective nonproliferation measure. Pedestrian and vehicle portal monitors have been an established tool for preventing the unauthorized movement of SNM across US nuclear facility boundaries for 15 years. Because the portals are reliable and easy to install, they are an efficient first step to improve the security at Russian nuclear facilities. The portals were first furnished to Russian facilities for testing and evaluation. After Russian technical experts gained experience with the operating parameters, the instruments were implemented at appropriate locations at each facility. This process has been executed at IPPE, VNIEF, VNIITF, RCC KI, and SKhK. The transfer of the portal monitoring technology to Russian institutes to promote the manufacture of Russian instruments is also an important goal of the program. The process was started with two portal monitor workshops attended by representatives of Russian facilities at ORNL and followed by technical collaborations at the individual Russian facilities. The success of this effort is illustrated by the recent workshop hosted by VNIIA at the SCI in Obninsk where specialists from thirty-two Russian nuclear facilities met to discuss their experience in portal monitoring. Twelve institutes and firms reported on the status of Russian designed and manufactured instruments. Details of this program will be presented in this paper.
Date: May 1, 1997
Creator: York, R.L.
Partner: UNT Libraries Government Documents Department

Portal monitoring technology control process

Description: Portal monitors are an important part of the material protection, control, and accounting (MPC and A) programs in Russia and the US. Although portal monitors are only a part of an integrated MPC and A system, they are an effective means of controlling the unauthorized movement of special nuclear material (SNM). Russian technical experts have gained experience in the use of SNM portal monitors from US experts ad this has allowed them to use the monitors more effectively. Several Russian institutes and companies are designing and manufacturing SNM portal monitors in Russia. Interactions between Russian and US experts have resulted in improvements to the instruments. SNM portal monitor technology has been effectively transferred from the US to Russia and should be a permanent part of the Russian MPC and A Program. Progress in the implementation of the monitors and improvements to how they are used are discussed.
Date: December 31, 1998
Creator: York, R.L.
Partner: UNT Libraries Government Documents Department

Development of a multicusp H/sup -/ ion source for accelerator applications

Description: The development of a multicusp surface-production H/sup -/ ion source (Berkeley concept) designed specifically for accelerator use is described. The goal of this development effort has been to provide a suitable H/sup -/ ion source for the Proton Storage Ring now being constructed at LAMPF. The ion source that has been developed is now capable of long-term operation at 20 mA of H/sup -/ current at 10% duty factor and with normalized beam emittance of 0.13 cm-mrad (95% beam fraction). The development program will be described with particular emphasis on beam emittance measurements.
Date: January 1, 1983
Creator: York, R.L. & Stevens, R.R. Jr.
Partner: UNT Libraries Government Documents Department

1997 update for the applications guide to vehicle SNM monitors

Description: Ten years have elapsed since the publication of the original applications guide to vehicle special nuclear material (SNM) monitors. During that interval, use of automatic vehicle monitors has become more commonplace, and formal procedures for monitor upkeep and evaluation have become available. New concepts for vehicle monitoring are being explored, as well. This update report reviews the basics of vehicle SNM monitoring, discusses what is new in vehicle SNM monitoring, and catalogs the vehicle SNM monitors that are commercial available.
Date: April 1, 1997
Creator: York, R.L. & Fehlau, P.E.
Partner: UNT Libraries Government Documents Department

Collection of High Energy Yielding Strains of Saline Microalgae from the Hawaiian Islands: Final Technical Report, Year 1

Description: Microalgae were collected from 48 locations in the Hawaiian Islands in 1985. The sites were an aquaculture tank; a coral reef; bays; a geothermal steam vent; Hawaiian fish ponds; a Hawaiian salt punawai (well); the ocean; river mouths; saline lakes; saline pools; saline ponds; a saline swamp; and the ponds, drainage ditches and sumps of commercial shrimp farms. From 4,800 isolations, 100 of the most productive clones were selected to be maintained by periodic transfer to sterile medium. Five clones were tested for growth rate and production in a full-spectrum-transmitting solarium.
Date: January 1, 1986
Creator: York, R. H.
Partner: UNT Libraries Government Documents Department

Report on Design, Development, and Characterization of a Coaxial Resonator Based Single-gap Gridless Multiharmonic Buncher

Description: The design of the multiharmonic buncher is determined by Facility for Rare Isotope Beam (FRIB) requirements. The buncher will bunch stable ion beams for injection into the FRIB RFQ to minimize the longitudinal beam emittance growth. The design beam energy is fixed at 12 keV/u while the beam charge state Q/A can vary from 1/3 to 1/7. The buncher operates at a fundamental frequency of 40.25 MHz. Two higher harmonics, 80.5 MHz and 120.75 MHz are used to linearize the voltage ramp. The typical accelerating voltage for a uranium beam, including the time-of-flight factor, is 1271 V, 456 V, and 150 V for 40.25 MHz, 80.5 MHz, and 120.75 MHz harmonics respectively. The voltage will be scaled with the charge state of an accelerated beam. The accelerated electrical beam current is expected to be approximately equal to 0.5 mA for all ion beams between oxygen and uranium.
Date: February 11, 2013
Creator: Pozdeyev, E; Brandon, J; Bultman, N; Rao, X; York, R & Zhao, Q
Partner: UNT Libraries Government Documents Department

Longitudinal space charge effects near transition

Description: Experimental and numerical studies of the longitudinal beam dynamics in the Small Isochronous Ring (SIR) at Michigan State University revealed a fast, space-charge driven instability that did not fit the model of the negative mass instability. This paper proposes a simple analytical model explaining these results. Also, the paper compares the model to result s of experimental and numerical studies of the longitudinal beam dynamics in SIR.
Date: May 4, 2009
Creator: Pozdeyev,E.; Rodriguez, J.A.; Marti, F. & York, R.C.
Partner: UNT Libraries Government Documents Department

Space charge effect in isochronous rings

Description: Cyclotrons, rings for precise nuclear mass spectrometry, and some light sources with extremely short bunches are operated or planned to be operated in the isochronous or almost isochronous regime. Also, many hadron synchrotrons run in the isochronous regime for a short period of time during transition crossing. The longitudinal motion is frozen in the isochronous regime that leads to accumulation of the integral of the longitudinal space charge force. In low-gamma hadron machines, this can cause a fast growth of the beam energy spread even at modest beam intensities. Additionally, the transverse component of the space charge effectively modifies the dispersion function and the slip factor shifting the isochronous (transition) point. In this paper, we discuss space charge effects in the isochronous regime and present experimental results obtained in the Small Isochronous Ring, developed at Michigan State University specifically for studies of space charge in the isochronous regime.
Date: August 25, 2008
Creator: Pozdeyev,E.; Rodriguez, J.A.; Marti, F. & York, R.
Partner: UNT Libraries Government Documents Department

An Investigation of the Influence of Chain Length on the Interfacial Ordering of L-Lysine and L-Proline and Their Homopeptides at Hydrophobic and Hydrophilic Interfaces Studied by Sum Frequency Generation and Quartz Crystal Microbalance

Description: Sum frequency generation vibrational spectroscopy (SFG) and quartz crystal microbalance with dissipation monitoring (QCM-D) are employed to study the interfacial structure and adsorbed amount of the amino acids l-lysine and l-proline and their corresponding homopeptides, poly-l-lysine and poly-l-proline, at two liquid-solid interfaces. SFG and QCM-D experiments of these molecules are carried out at the interface between phosphate buffered saline at pH 7.4 (PBS) and the hydrophobic deuterated polystyrene (d{sub 8}-PS) surface as well as the interface between PBS and hydrophilic fused silica (SiO{sub 2}). The SFG spectra of the amino acids studied here are qualitatively similar to their corresponding homopeptides; however, the SFG signal from amino acids at the solid/PBS interface is smaller in magnitude relative to their more massive homopeptides at the concentrations studied here. Substantial differences are observed in SFG spectra for each species between the hydrophobic d{sub 8}-PS and the hydrophilic SiO{sub 2} liquid-solid interfaces, suggesting surface-dependent interfacial ordering of the biomolecules. Over the range of concentrations used in this study, QCM-D measurements also indicate that on both surfaces poly-l-lysine adsorbs to a greater extent than its constituent amino acid l-lysine. The opposite trend is demonstrated by poly-l-proline which sticks to both surfaces less extensively than its corresponding amino acid, l-proline. Lastly, we find that the adsorption of the molecules studied here can have a strong influence on interfacial water structure as detected in the SFG spectra.
Date: February 23, 2009
Creator: York, R.L.; Holinga, G.J. & Somorjai, G.A.
Partner: UNT Libraries Government Documents Department

Design of an electron beam spectral modification system

Description: We report the design of a spectral modification system (SMS) for use with the proposed NEAL linac-pulse stretcher ring, cw electron beam facility. The SMS allows tailoring of the energy distribution of electrons in beams produced by a pulsed linac operating in the transient beam loading (TBL) regime. Modification of the energy distribution of electrons injected into the pulse strecher ring will increase the duty factor of current extracted from the ring and improve the efficiency of the extraction process. Physically, the SMS consists of an anisochronous, achromatic magnetic lattice followed by a pair of traveling-wave accelerating sections. For beams in the energy range of 500 MeV to 4 GeV, TBL ripple on the energy envelope of microsecond long beam spills is expected to be reduced from 1% peak-peak to less than 0.01% while the desired width of the energy profile due to the phase extent of the microbunches in the beam spill is preserved.
Date: October 1, 1981
Creator: Sheppard, J.C.; York, R.C.; Norum, B.E. & McCarthy, J.S.
Partner: UNT Libraries Government Documents Department

Estimated and observed performance of a neutron SNM portal monitor for vehicles

Description: In July 1987, we completed our development of a neutron-detection- based vehicle SNM portal monitor with a conference paper presented at the annual meeting. The paper described the neutron vehicle portal (NVP), described source-response measurements made with it at Los Alamos, and gave our estimate of the monitor`s potential performance. Later, in December 1988, we had a chance to do a performance test with the monitor in a plant environment. This paper discusses how our original performance estimate should vary in different circumstances, and it uses the information to make a comparison between the monitor`s estimated and actual performance during the 1988 performance testing.
Date: November 1, 1996
Creator: Fehlau, P.E.; Close, D.A.; Coop, K.L. & York, R.
Partner: UNT Libraries Government Documents Department

An Optimized International Vehicle Monitor

Description: This is the final report of a one-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The goal of this project was to evaluate detector configurations to achieve a vehicle monitor that is economical, practical to install, and has adequate sensitivity to be an effective barrier to illegal transportation of special nuclear materials. We designed a new detector configuration that improves the sensitivity of available drive-through vehicle monitors by more than a factor of 5 while not changing the nuisance alarm rate.
Date: July 16, 1999
Creator: York, R.L.; Close, D.A. & Fehlau, P.E.
Partner: UNT Libraries Government Documents Department

Betatron Function Parameterization of Beam Optics including Acceleration

Description: Betatron function parameterization of symplectic matrices is of recognized utility in beam optical computations. The traditional ''beta functions'' beta, alpha, gamma,(=(1+alpha{sup 2})/beta) and psi (the betratron phase advance) provide an emittance-independent representation of the properties of a beam transport system. They thereby decouple the problem of ''matching'' injected beam envelope properties to the acceptance of a particular transport system from the details of producing a beam of a specific emittance. The definition and interpretation of these parameters becomes, however, more subtle when acceleration effects, especially adiabatic damping (with associated nonsymplecticity of the transfer matrix), are included. We present algorithms relating symplectic representations of beam optics to the more commonly encountered nonsymplectic (x, x', y, y') representation which exhibits adiabatic damping. Betatron function parameterizations are made in both representations. Self-consistent physical interpretations of the betatron functions are given and applications to a standard beam transport program are made.
Date: October 1, 1988
Creator: Douglas, D.R.; Kewisch, J. & York, R.C.
Partner: UNT Libraries Government Documents Department

Exporting automatic vehicle SNM monitoring technology

Description: Controlling the transportation of nuclear materials is still one of the most effective nuclear proliferation barriers. The recent increase of global nuclear material proliferation has expanded the application of vehicle monitor technology to prevent the diversion of special nuclear material across international borders. To satisfy this new application, a high-sensitivity vehicle monitor, which is easy to install and capable of operating in high-traffic areas, is required. A study of a new detector configuration for a drive-through vehicle monitor is discussed in this paper.
Date: October 1, 1995
Creator: York, R.L.; Fehlau, P.E. & Close, D.A.
Partner: UNT Libraries Government Documents Department

Development of a toroidal-filter H{sup {minus}} ion source

Description: High brightness H{sup {minus}} ion beams will be required for the next generation of accelerator-driven, neutron spallation sources. Volume H{sup {minus}} ion sources have the potential for providing these beams at high duty factor with moderate beam currents and with the long-term operational stability and reliability needed. The authors report on the results of a continuing study of the LANL version of a toroidal-filter, volume H{sup {minus}} ion source which was designed to provide such beams. The H{sup {minus}} beam current, emittance, and electron loading have been measured with the source equipped with a 3-mm and a 10-mm dia. emission aperture and with several configurations of the plasma filter. The results are compared to beam simulations.
Date: September 1, 1995
Creator: Stevens, R.R. Jr.; York, R.L.; Geisik, C. & Swenson, D.R.
Partner: UNT Libraries Government Documents Department

Optical pumping for intense polarized ion sources

Description: Laser optical pumping without buffer gas in dense (NL>10/sup 12/ atoms/cm/sup 2/) sodium vapor targets was investigated. The atomic polarization of the target was determined from the Faraday rotation angle of a second dye laser tuned midway between the sodium D-lines. Substantial polarizations were measured even though the pump laser bandwidth (approx. 1 MHz) was much smaller than the Doppler and hyperfine broadened sodium absorption line (approx. 3 GHz). Theoretical calculations based on rate equations in an idealized 3-level, ..lambda..-type system adequately reproduce the data. These calculations predict very high polarizations (P>0.8) at power levels produced in commercially available ring dye lasers.
Date: January 1, 1982
Creator: Cornelius, W.D.; Taylor, D.J.; York, R.L. & Hinds, E.A.
Partner: UNT Libraries Government Documents Department

The H sup + ECR source for the LAMPF Optically Pumped Polarized Ion Source

Description: An ECR source is used to produce the H{sup +} beam for the Optically Pumped Polarized Ion Source (OPPIS) at LAMPF. OPPIS requires a very high H{sup +} beam brightness from the ECR source. Studies of ECR extraction geometries that best fulfill this requirement are presented. 8 refs., 4 figs., 1 tab.
Date: January 1, 1990
Creator: York, R.L. & Tupa, D.
Partner: UNT Libraries Government Documents Department

Operation of the optically pumped polarized H sup minus source at LAMPF

Description: We report on the first five months of operation of the Optically Pumped Polarized Ion Source (OPPIS) for the nuclear physics research program at LAMPF. The LAMPF OPPIS is unique in using Ti: Sapphire lasers to polarize the potassium charge-exchange medium, and until recently was unique in using a superconducting magnet in the ECR source and polarizer regions. The ECR extraction electrode biasing arrangement is also unique. Typical performance was 25 microamps of peak current (measured at 750 keV) with 55% beam polarization or 15 microamps at 62%. Ion source availability was greater than 90%. We also report our planned improvements in preparation for research operation in May of 1991. 3 refs., 4 figs.
Date: January 1, 1991
Creator: York, R.L.; Tupa, D.; Swenson, D.R. & van Dyck, O.B.
Partner: UNT Libraries Government Documents Department

Injector operations at LAMPF

Description: The injector complex at LAMPF consists of three on-line 750-kV injectors which provide simultaneous H/sup +/ and H/sup -/ beams for LAMPF production and an off-line 200-keV injector for ion source and beam diagnostic development studies. The present operation now entails a 500-..mu..A/sub a/ H/sup +/ beam accelerated simultaneously with either a 6-..mu..A/sub a/ unpolarized or 10-nA/sub a/ polarized H/sup -/ beam. In order to obtain the low-beam spill required for the operation of the LAMPF accelerator, it has been necessary to increase the brightness of the high-intensity H/sup +/ beam. The operating experience and development work that has been carried out on all of these injectors to improve the quality and intensity of these beams will be presented. The details of the construction of the test stand injector and the development program planned for this injector will also be outlined.
Date: January 1, 1979
Creator: Stevens, R.R. Jr.; McConnell, J.R.; Chamberlin, E.P.; Hamm, R.W. & York, R.L.
Partner: UNT Libraries Government Documents Department

Optical pumping of the polarized H sup minus ion source at LAMPF

Description: We report experiments to understand the laser optical pumping efficiency for the Optically Pumped Polarized Ion Source (OPPIS) at LAMPF. We have measured ion beam polarization and current vs. laser power and potassium vapor thickness in order to understand the dependence of source performance on laser power and other parameters. Attempts to fit the data with simple scaling models to evaluate projected performance improvements are shown. Development of economical ways to make more efficient use of available laser power are described. 4 refs., 4 figs.
Date: May 1, 1991
Creator: Swenson, D.R.; Tupa, D.; van Dyck, O.B. & York, R.L.
Partner: UNT Libraries Government Documents Department

Beam dynamics calculations for the LAMPF optically pumped ion source

Description: The space charge code SCHAR has been used to interpret some of the measurements made with the LAMPF ECR source. Calculations were made for rectangular hole, single hole and multihole electrodes. Measured rotation of the plane of the ribbon beam in the constant solenoid field showed that when the polarizer cell was not utilized the beam was essentially not neutralized after it emerged from the extraction electrodes. There is evidence that when the polarizer cell is ''turned on'' the beam becomes neutralized from the polarizer back toward the electrode structure. The total measured current from single and multihole electrodes with the polarizer cell ''on'' is proportional to the area of the electrode apertures. Beam simulation calculations indicate that if the beam extracted from the source is uniform across the multihole structure, then in order for the perimeter holes to provide as much current per area, the beam would have to be at least partially neutralized after existing from the electrode structure. POISSON calculated fields were used for the single and multihole electrode fields. For a ribbon beam the field used was that of a very long slit. The initial transverse velocity and energy of the beam at the entrance to the three electrodes were adjusted to provide agreement with the measured harp histograms. The energy of the ions leaving the (unmodeled) ECR plasma determines the current for a given electrode structure and voltage. Initial transverse velocity was not a sensitive parameter. Electrode radial fields and beam space charge forces generate most of the transverse velocities observed as the beam exits from the electrodes. ''Tails'' which were present in the measured harp data could be explained by an H/sub 2//sup +/ component in the beam. 3 refs., 6 figs.
Date: January 1, 1989
Creator: Hayden, R.J.; Jakobson, M.J.; van Dyck, O.B. & York, R.L.
Partner: UNT Libraries Government Documents Department

Operation of a magnetically filtered multicusp volume source

Description: The results of experimental studies on an optimized version of the Lawrence Berkeley Laboratory (LBL) volume source are presented. Negative ion yields and emittance data were obtained for operation with both H/sup -/ and D/sup -/ beams. At high arc power, H/sup -/ beam currents up to 10 mA with rms normalized emittances of 0.0080 ..pi...cm.mrad were obtained from a 6.3-mm-dia emission aperture. The yields of D/sup -/ beams were approximately half those of H/sup -/ beams, and the normalized emittances were 1.7 times smaller at the same current density. The results of these studies indicate that the present operation is limited by the extraction system rather than the ion source.
Date: January 1, 1986
Creator: Stevens, R.R. Jr.; York, R.L.; Leung, K.N. & Ehlers, K.W.
Partner: UNT Libraries Government Documents Department