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Development of a low intensity current monitor system

Description: This report documents the development of a current transformer system used to measure pulsed ion beam currents with a wide dynamic intensity range (nA to mA, and factor of 10{sup 6}). Peak beam currents at the LAMPF accelerator typically range from 100 to nA to 40 mA with pulse widths varying from 30 to 1000 {mu}s. Signal conditioning of the peak current output provides an average current readout with a range of 1 nA to 2 mA, noise of approximately {plus minus}0.5 nA, and accuracy of {plus minu… more
Date: January 1, 1991
Creator: Gallegos, F.R.
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Partner: UNT Libraries Government Documents Department
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First order tune shift calculations for transverse betatron dynamics

Description: An effective Hamiltonian, with non-linear magnetic multipole terms and momentum dispersion contributions, is used to obtain the first order tune-shift results for transverse betatron motion for protons in the Superconducting Super Collider (SSC). This Hamiltonian is represented in terms of action angle variables, and analytical results are obtained using symbolic algebra methods. Mathematical derivations of the transverse multipole expansion and of the transverse betatron equations, using an in… more
Date: September 1, 1991
Creator: Garavaglia, T.
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Partner: UNT Libraries Government Documents Department
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Proposed partitioning and transmutation of long-lived nuclear wastes

Description: A means of transmuting key long-lived nuclear wastes, primarily the minor actinides (Np, Am, Cm) and iodine, using a hybrid proton accelerator and sub-critical lattice, is proposed. By partitioning light water reactor (LWR) spent fuel and by transmuting key elements, such as the plutonium, the minor actinides, and a few of the long-lived fission products, some of the most significant challenges in building a waste repository can be substantially reduced. The proposed machine would transmute the… more
Date: January 1, 1991
Creator: Van Tuyle, G.J. (Brookhaven National Lab., Upton, NY (United States)) & Rawlins, J.A. (Westinghouse Hanford Co., Richland, WA (United States))
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Partner: UNT Libraries Government Documents Department
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Accelerator-driven sub-critical target concept for transmutation of nuclear wastes

Description: A means of transmuting key long-lived nuclear wastes, primarily the minor actinides (Np, Am, Cm) and iodine, using a hybrid proton accelerator and sub-critical lattice, is proposed. By partitioning the components of the light water reactor (LWR) spent fuel and by transmuting key elements, such as the plutonium, the minor actinides, and a few of the long-lived fission products, some of the most significant challenges in building a waste repository can be substantially reduced. The proposed machi… more
Date: January 1, 1991
Creator: Van Tuyle, G. J.; Todosow, M.; Aronson, A. L.; Takahashi, H. (Brookhaven National Lab., Upton, NY (United States)) & Geiger, M. J. (Military Academy, West Point, NY (United States))
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Partner: UNT Libraries Government Documents Department
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Neutronics parameter variation studies for the Los Alamos ATW concept

Description: The purpose of the Los Alamos ATW (Accelerator Transmutation of nuclear Waste) project is to utilize a high-energy (800--1600 MeV), high current (25--60mA) proton beam to generate a large neutron flux for the transmutation of nuclear wastes. Our theoretical modeling efforts have been directed toward designing a device that will transmute the 2000 kg of Tc and I in the Hanford waste depository along with significant quantities of actinides. Previous system studies have indicated the feasibility … more
Date: January 1, 1991
Creator: Krohn, B.J.; Perry, R.T. & Sapir, J.L.
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Partner: UNT Libraries Government Documents Department
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A Faraday Cup with high frequency response for a 200 MeV LINAC proton beam

Description: The purpose of this device, composed essentially of coaxial line elements, is monitoring, on a per micropulse basis, the beam intensity of a 200 MeV LINAC at the BNL Radiation Effects Facility. The center conductor of the coaxial line acts as a beam stop. The output pulses are suitable for fast timing. 2 refs., 5 figs.
Date: January 1, 1991
Creator: Zucker, M.S. & Bittner, J.W.
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Partner: UNT Libraries Government Documents Department
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Advanced high brightness ion rf accelerator applications in the nuclear energy

Description: The capability of modern rf linear accelerators to provide intense high quality beams of protons, deuterons, or heavier ions is opening new possibilities for transmuting existing nuclear wastes, for generating electricity from readily available fuels with minimal residual wastes, for building intense neutron sources for materials research, for inertial confinement fusion using heavy ions, and for other new applications. These are briefly described, couched in a perspective of the advances in th… more
Date: January 1, 1991
Creator: Jameson, Robert A.
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Partner: UNT Libraries Government Documents Department
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Observations of the PSR transverse instability

Description: A fast instability with beam loss is observed in the Los Alamos Proton Storage Ring (PSR) when the injected beam current exceeds thresholds, with both bunched and unbunched beams. Large coherent transverse oscillations occur before and during beam loss. Recent observations of the instability indicate that it is an e-p''-type instability, driven by coupled oscillations due to electrons trapped within the proton beam. 5 refs., 3 figs.
Date: January 1, 1991
Creator: Colton, E.; Fitzgerald, D.; Hardek, T.; Macek, R. J.; Plum, M. A.; Thiessen, H. A. et al.
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Partner: UNT Libraries Government Documents Department
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Monte Carlo simulations of models for accelerator transmutation of waste

Description: The Los Alamos Accelerator Transmutation of Waste (ATW) program is directed toward the dual goals of alleviating the problems associated with existing high-level radioactive defense wastes, and of developing systems for the generation of fission energy with minimal production of high-level, long-lived nuclear wastes. In the Los Alamos ATW concept, a high-current, high-energy proton accelerator creates and intense flux of neutrons through spallation in heavy metal targets. The high neutron flux … more
Date: January 1, 1991
Creator: Hughes, H.G. & Engel, L.N.
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Partner: UNT Libraries Government Documents Department
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Observation and analysis of time-dependent closed orbit motion in the LAMPF Proton Storage Ring

Description: When the stored beam is artificially offset in a section of the LAMPF Proton Storage Ring by changing selected ring dipole strengths, there is evidence for a small time dependence of the offset during the course of beam injection. A complete discussion of the time dependence of orbit offsets should take into account at least the following possibilities: (1) correlations between the injection timing pattern and ring dipole field ripple, (2) correlations between the injection timing pattern and c… more
Date: January 1, 1991
Creator: Hutson, R.L.; Fitzgerald, D.H. & Macek, R.J.
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Partner: UNT Libraries Government Documents Department
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A pinger system for the Los Alamos Proton Storage Ring

Description: Developers at the Proton Storage Ring have long desired a modulator and electrode combination capable of kicking the 800-MeV proton beam enough to conduct tune measurements with full intensity beams. At present this has been accomplished by reducing the voltage on one extraction kicker modulator and turning the other off. This method requires that all of the accumulated beam be lost on the walls of the vacuum chamber. In addition to tune measurements a more recent desire is to sweep out beam th… more
Date: January 1, 1991
Creator: Hardek, T.W. & Thiessen, H.A.
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Partner: UNT Libraries Government Documents Department
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High-power proton linac for transmuting the long-lived fission products in nuclear waste

Description: High power proton linacs are being considered at Los Alamos as drivers for high-flux spallation neutron sources that can be used to transmute the troublesome long-lived fission products in defense nuclear waste. The transmutation scheme being studied provides a high flux (> 10{sup 16}/cm{sup 2}{minus}s) of thermal neutrons, which efficiently converts fission products to stable or short-lived isotopes. A medium-energy proton linac with an average beam power of about 110 MW can burn the accumulat… more
Date: January 1, 1991
Creator: Lawrence, G. P.
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Partner: UNT Libraries Government Documents Department
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Free-radical yield in proton irradiation of oriented DNA: Relationship to energy transfer along DNA chains

Description: Spatial patterns of energy deposition on the nanometer scale are currently believed to be a major factor in determining the biological effectiveness of ionizing radiation. If the most common precursors of biologically significant lesions are clusters of ionization in or near DNA, then intramolecular energy and charge transfer along DNA chains could be very important in lesion development. This paper describes investigations of these phenomena through model calculations and measurements of radic… more
Date: October 1, 1991
Creator: Miller, J.H.; Frasco, D.L.; Ye, M. (Pacific Northwest Lab., Richland, WA (United States)); Swenberg, C.E.; Myers, L.S. Jr. (Armed Forces Radiobiology Research Inst., Bethesda, MD (United States)) & Rupprecht, A. (Stockholm Univ. (Sweden))
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Partner: UNT Libraries Government Documents Department
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Polarized protons and RHIC

Description: RHIC, the heavy ion collider being built at Brookhaven, offers an exciting opportunity to collide highly polarized protons at high energy and luminosity. This new facility would combine the existing AGS polarized proton capability with the new Booster/Accumulator and spin rotators to achieve collisions between intense beams of polarized protons at a collision energy of 500 GeV. At this energy and the expected luminosity of 2 {times} 10{sup 32} cm{sup 2}/second physics probes will include high P… more
Date: December 1, 1991
Creator: Bunce, G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Radiation shielding tests in the Meson beamline in the master substation area

Description: A review of shielding uncovered a weak region in a portion of the proton beam transport to the Meson Area. Preliminary CASIM Monte Carlo studies indicated dose rates at the surface under abnormal operating conditions would be above the Fermilab Radiation Guide limits. Measurements made on December 15 and 16 confirmed this concern. Further comparisons of data with CASIM predictions are discussed. 5 refs., 22 figs., 8 tabs.
Date: April 1, 1991
Creator: Coleman, R.; Kissel, W.; Leveling, A.; Moore, C.D. & Vylet, V.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Comment on Measurement of the Z sub 1 sup 3 contribution to the stopping power using MeV protons and antiprotons, the Barkas effect''

Description: In a recent Letter, Andersen et al. reported measured energy losses of 0.5--3.0 MeV protons and antiprotons in silicon and extracted the Z{sub 1}{sup 3} (or Barkas) correction to the stopping power. They compared their results to calculations that are valid for distant collisions and are based on a perturbation expansion for the excitation of a classical harmonic oscillator. The authors mentioned that there has been a long-standing discussion about the contribution from close collisions to the … more
Date: January 1, 1991
Creator: Mikkelsen, H.H. (Odense Univ. (Denmark)); Esbensen, H. (Argonne National Lab., IL (USA)) & Sigmund, P. (Argonne National Lab., IL (USA) Odense Univ. (Denmark))
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Siberian Snake solenoid for the AGS

Description: Recent experiments at the Indiana University Cyclotron Facility (IUCF) have demonstrated that Siberian Snakes'' can be used to preserve the polarization of an accelerated polarized beam in a circular accelerator. Retrofitting full snakes into accelerators such as the Alternating Gradient Synchrotron (AGS) at Brookhaven is almost impossible due to space limitations, but a partial snake that can correct depolarization due to imperfection resonances with 1/20 to 1/30 of a full strength snake seems… more
Date: January 1, 1991
Creator: Ratner, L. G.
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Partner: UNT Libraries Government Documents Department
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Super slow extraction at the SSC using channeling in a curved crystal

Description: The possibility of a high-precision B-physics experiment in a fixed target configuration has stimulated considerable interest in the extraction of a low-intensity proton beam from the SSC during collider operation. The candidate scheme which has received the most attention uses a bent crystal of Si to deflect protons into the extraction line. In this paper, we present results on deflecting efficiency of Si(110) planes and on the feeding of the crystal by controlled injection of noise into the c… more
Date: October 1, 1991
Creator: Newberger, B.S. (Texas Univ., Austin, TX (United States). Inst. for Fusion Studies); Shih, H.J. (Superconducting Super Collider Lab., Dallas, TX (United States)) & Ellison, J.A. (New Mexico Univ., Albuquerque, NM (United States))
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A pulsed lepton source at LAMPF

Description: A Pulsed Lepton Source is being considered at the LAMPF facility at Los Alamos National Laboratory. The source plan is described together with a description of the components and performance as they exist at present. 9 figs.
Date: November 22, 1991
Creator: White, D. Hywel
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Partner: UNT Libraries Government Documents Department
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An ESME update (v. 7. 2)

Description: The program ESME for modeling the longitudinal degree of freedom of beam dynamics in proton synchrotrons was described in considerable detail in User's Guide to ESME v. 7.1'' distributed about a year ago. This note corrects minor errors and omissions in the User's Guide, discusses bugs and crochets, notes fixes, and reports a few enhancements. Current work and plans are sketched. This note should be adequate to update the User's Guide. 8 refs.
Date: February 11, 1991
Creator: MacLachlan, J.A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Realistic modeling of microwave instability effects on the evolution of the beam energy-phase distribution in proton synchrotrons

Description: Either bunched or coasting beam in a synchrotron may exhibit microwave instability of the momentum spread is small. A useful physical picture is that beam particles are captured in buckets generated by the beam image current flowing in the longitudinal coupling impedance. Qualitatively, trapping and auto-deceleration occur when the height of the buckets exceed the FWHM energy spread of the beam. Microwave instability implies in addition that the coupling impedance is largest at several times th… more
Date: January 1, 1991
Creator: MacLachlan, J.A.
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Partner: UNT Libraries Government Documents Department
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Accelerator technology for the Los Alamos ATW (accelerator transmutation of nuclear waste) system

Description: The Los Alamos concept for accelerator transmutation of nuclear waste (ATW) employs a high-power proton linear accelerator to generate intense fluxes of thermal neutrons (>10{sup 16} n/cm{sup 2}-s) through spallation on a lead-bismuth target. The nominal beam energy for an ATW accelerator is 1.6 GeV, with average current requirements ranging from 250 mA to 30 mA, depending on application specifics. A recent study of accelerator production of tritium (APT) led to the development of a detailed po… more
Date: January 1, 1991
Creator: Lawrence, G. P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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