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7-GeV Advanced Photon Source Beamline Initiative. Conceptual Design Report

Description: The DOE is building a new generation 6-7 GeV Synchrotron Radiation Source known as the Advanced Photon Source (APS) at Argonne National Laboratory. This facility, to be completed in FY 1996, can provide 70 x-ray sources of unprecedented brightness to meet the research needs of virtually all scientific disciplines and numerous technologies. The technological research capability of the APS in the areas of energy, communications and health will enable a new partnership between the DOE and US indus… more
Date: May 1993
Creator: Argonne National Laboratory
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A beamline design and data acquisition with the 20-MeV, 20-ps electron beam for the higher-order mode studies of the APS SR-rf cavities

Description: A beamline has been designed and assembled to use the ANL Chemistry Division 20-MeV electron linac for the testing of higher-order mode excitation and damping in rf cavities. The beamline consists of two sections (a beam collimating section with a 1.5 inches-OD vacuum line, and a cavity test section with a 3 inches-OD vacuum line), separated by two double aluminum foil windows. The beam diagnostics consist of a stripline beam position monitor, integrating current transformers, fluorescent scree… more
Date: January 1, 1993
Creator: Song, J.; Nassiri, A. & Daly, R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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High precision beam alignment of electromagnetic wigglers

Description: The performance of Free-Electron Lasers depends critically on the quality of the alignment of the electron beam to the wiggler's magnetic axis and the deviation of this axis from a straight fine. The measurement of the electron beam position requires numerous beam position monitors in the wiggler, where space is at premium. The beam position measurement is used to set beam steerers for an orbit correction in the wiggler. The authors propose an alternative high precision alignment method in whic… more
Date: January 1, 1993
Creator: Ben-Zvi, Ilan & Qiu, X. Z.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Performance of production SRF cavities for CEBAF

Description: Construction of the Continuous Electron Beam Accelerator Facility recirculating linac represents the largest scale application of superconducting rf (SRF) technology to date. Over 250 of the eventual 338 SRF 1497 MHz cavities have been assembled into hermetic pairs and completed rf testing at 2.0 K. Although the rf performance characteristics well exceed the CEBAF baseline requirements of Q[sub 0] = 2.4[times]10[sup 9] at 5 MV/m, the usual limiting phenomena are encountered field emission, quen… more
Date: June 1, 1993
Creator: Reece, C.; Benesch, J.; Kneisel, P.; Kushnick, P.; Mammosser, J. & Powers, T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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SLAC measurement of the neutron spin structure function

Description: A measurement of the nucleon spin asymmetries from deep inelastic scattering of polarized electrons by polarized [sup 3]He has been performed. The neutron spin structure function g[sub 1][sup n] is extracted and used to test the Bjorken sum rule. The neutron integral assuming a simple Regge theory extrapolation at low x is [integral][sub 0][sup 1]g[sub 1][sup n](x)dx = [minus]0.022 [plus minus] 0.011. Combined with the EMC proton results, the Bjorken sum rule predicts a neutron integral of [int… more
Date: April 1, 1993
Creator: Hughes, E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Investigation of the coherent synchrotron radiation spectrum as a probe of charge dynamics

Description: Coherent synchrotron, Cherenkov and transition radiation have generated and measured in the far infrared spectral region. This work represents the first identification and separation of the Cherenkov and transition radiation components with transition radiation producing the strongest signal. High-intensity picosecond pulses of radiation are observed for all three sources. The angular dependence in the mm wave region is not the same as that given by high-frequency radiation expressions since th… more
Date: February 1, 1993
Creator: Sievers, A.J. & Tigner, M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Impedance of the NSLS prototype small-gap undulator vacuum chamber

Description: Insertion device performance is limited by the minimum magnet gap allowed by storage ring beam dynamics. In this note, we analyze the impedance of the vacuum chamber for the prototype small-gap undulator being built for the NSLS X-Ray ring, and discuss the consequent beam instability thresholds.
Date: March 1, 1993
Creator: Bane, K. (Stanford Linear Accelerator Center, Menlo Park, CA (United States)) & Krinsky, S. (Brookhaven National Lab., Upton, NY (United States))
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Parity nonconservation in proton scattering at higher energies

Description: A parity-nonconservation experiment in the scattering of longitudinally-polarized protons at an incident proton momentum of 6 GeV/c is examined. This experiment indicates a sharp rise with energy of the total cross section correlated with proton helicity that was unexpected. This energy dependence is due to the strong part of the interaction and may indicate the role of a diquark component in the nucleon. New experiments at higher energies are needed to confirm such a model. Future experiment c… more
Date: January 1, 1993
Creator: Mischke, R.E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Hydrodynamic calculations of 20-TeV beam interactions with the SSC beam dump

Description: The 300[mu]s, 400 MJ SSC proton beam must be contained when extracted to the external beam dump. The current design for the SSC beam dump can tolerate the beat load produced if the beam is deflected into a raster scan over the face of the dump. If the high frequency deflecting magnet were to fail, the beam would scan a single strip across the dump face resulting in higher local energy deposition. This could vaporize some material and lead to high pressures. Since the beam duration is comparable… more
Date: January 1, 1993
Creator: Wilson, D. C.; Wingate, C. A.; Goldstein, J. C.; Godwin, R. P. (Los Alamos National Lab., NM (United States)) & Mokhov, N. V. (Superconducting Super Collider Lab., Dallas, TX (United States))
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Partner: UNT Libraries Government Documents Department
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Accelerator Research Studies

Description: The Accelerator Research Studies program at the University of Maryland, sponsored by the Department of Energy under grant number DE-FG05-91ER40642, is currently in the second year of a three-year funding cycle. The program consists of the following three tasks: TASK A, Study of Transport and Longitudinal Compression of Intense, High-Brightness Beams,'' (P.I., M. Reiser); TASK B, Study of Collective Ion Acceleration by Intense Electron Beams and Pseudospark Produced High Brightness Electron Beam… more
Date: January 1, 1993
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Wiggler as spin rotators for RHIC

Description: The spin of a polarized particle in a circular accelerator can be rotated with an arrangement of dipoles with field mutually perpendicular and perpendicular to the orbit. To achieve spin rotation, a given field integral value is required. The device must be designed in a way that the particle orbit is distorted as little as possible. It is shown that wigglers with many periods are suitable to achieve spin rotation with minimum orbit distortions. Wigglers are also more compact than more establis… more
Date: January 1, 1993
Creator: Luccio, A. & Conte, M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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First-turn losses in the LAMPF Proton Storage Ring (PSR)

Description: Beam-loss measurements protons injected into the PSR are lost during the first turn. We describe a plausible mechanism, involving field stripping of excited hydrogen atoms, for these losses. Protons are injected into the PSR by transporting a neutral hydrogen beam through a hole in the yoke of one ring bender and then through a carbon foil on the ring axis. The foil strips roughly 93% of the beam atoms to protons. Although the original PSR design assumed that all unstripped atoms would pass thr… more
Date: January 1, 1993
Creator: Hutson, R. & Macek, R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A flat-cathode thermionic injector for the PHERMEX Radiographic Facility

Description: The PHERMEX (Pulsed High-Energy Radiographic Machine Emitting X-rays) standing-wave linear accelerator is a high-current electron beam generator used for flash-radiography. An improved electron gun has been designed employing a flat-thermionic cathode to replace the existing Pierce-geometry gun. The flat cathode yields increased current with the same applied voltage and cathode area as the Pierce gun. The ISIS code simulations indicate a beam current of 1.5 kA at 600 kV. The new geometry also r… more
Date: January 1, 1993
Creator: Kauppila, T.; Builta, L.; Burns, M.; Gregory, W.; Honaberger, D.; Watson, S. (Los Alamos National Lab., NM (United States)) et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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High bandwidth beam current monitor

Description: A stripline directional coupler beam current monitor capable of measuring the time structure of a 30-ps electron beam bunch has been developed. The time response performance of the monitor compares very well with Cherenkov light produced in quartz by the electron beam. The four-pickup monitor is now used on a routine basis for measuring the beam duration, tuning for optimized beam bunching, and centering the bunch in the beam pipe.
Date: January 1, 1993
Creator: Baltrusaitis, R.M.; Ekdahl, C.A. (Los Alamos National Lab., NM (United States)); Cooper, R.G. (EG and G Energy Measurements, Inc., Goleta, CA (United States). Santa Barbara Operations); Peterson, E. & Warn, C.E. (EG and G Energy Measurements, Inc., Las Vegas, NV (United States). Las Vegas Operations)
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Prototype flying-wire beam-profile monitor

Description: A prototype flying-wire beam-profile monitor has been designed, fabricated and tested to measure profiles of highcurrent high-duty electron beams. The device measures the beam's horizontal and vertical profile with a pair of thin carbon filaments mounted on a wheel. The beam that intercepts the filaments, or wires, produces electrons by secondary emission in proportion to the incident beam current. The secondary electron signal is detected either by measuring the charge depletion current on the… more
Date: January 1, 1993
Creator: Barlow, D. B.; Fortgang, C. M.; Gilpatrick, J. D.; Meyer, R. E.; Rendon, A. M.; Warren, D. S. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Rigid-beam model of a high-efficiency magnicon

Description: The magnicon is a new type of high-efficiency deflection-modulated amplifier developed at the Institute of Nuclear Physics in Novosibirsk, Russia. The prototype pulsed magnicon achieved an output power of 2.4 MW and an efficiency of 73% at 915 MHz. This paper presents the results of a rigid-beam model for a 700-MHz, 2.5-MW 82%-efficient magnicon. The rigid-beam model allows for characterization of the beam dynamics by tracking only a single electron. The magnicon design presented consists of a … more
Date: January 1, 1993
Creator: Rees, D.E. & Tallerico, P.J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Measuring emittance using beam position monitors

Description: The Los Alamos Advanced Free Electron Laser uses a high charge (greater than InC), low emittance (normalized rams emittance less than 5[pi] mm mrad) photoinjector driven accelerator. The high brightness achieved is due, in large part, to the rapid acceleration of the electrons to relativistic velocities. As a result, the beam does not have time to thermalize its distribution and its universe profile is, in general, non-Gaussian. This, coupled with the very high brightness, makes it difficult to… more
Date: January 1, 1993
Creator: Russell, S. & Carlsten, B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Injector design for high-current CW proton linacs

Description: We present an injector design for high-power cw proton linacs with particular emphasis on intense neutron-spallation sources. Long-term operational reliability and availability dominate over specific beam parameters for these accelerators. We discuss technical requirements for the ion source and low-energy beam transport line and compare different options. A prototype design for a 75-kV, 110-mA cw proton injector is presented.
Date: January 1, 1993
Creator: Stevens, R. R. Jr.; Sherman, J. D. & Schneider, J. D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Future facilities for high-resolution ([pi], K) and other pion reactions at 1 GeV

Description: In 1991, the LAMPF Users considered a facility based on a pion linac (PILAC) to provide pions of up to 1 GeV for ([pi], K) and other pion reactions at LAMPF. We have extended this proposal to a version appropriate for high-energy proton accelerators by raising the pion injection energy and shortening the pion linac so that it is used as a rf separator and bunch rotator (SCRUNCHER). We have then estimated the yield of pions on target expected at LAMPF (PILAC), LAMPF assuming a proton energy upgr… more
Date: January 1, 1993
Creator: Thiessen, H.A. & Zumbro, J.D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Monte Carlo based formula for radiation shielding assessment in the forward direction

Description: Monte Carlo simulations of 800-MeV proton beam spills in common shielding materials show that neutron dose equivalent rates in the forward direction can be characterized by a Moyer Model-like formula. Particle transport codes were used to determine the neutron flux at depths up to 6 meters and for production angles from 0[degrees] to 30[degrees] for primary proton beam spills on cylindrical beam stops. The flux was then converted to dose equivalent rate as a function of depth and angle. The res… more
Date: January 1, 1993
Creator: Wilkinson, Carol A.; Fitzgerald, Daniel H.; Frankle, Stephanie C.; Hutson, Richard L. & Macek, Robert J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Nuclear fusion of protons with ions of boron

Description: This paper describes a method of extracting energy from the fusion events occurring between the collision of a beam of protons with a beam of ions of Boron 11. The two beams are circulating in separated and intersecting storage rings where they collide bead-on in a common long-straight section. Requirements on the luminosity of the low-energy collider are shown. Limitations due to space-charge and intrabeam scattering are described. Very fast electron cooling is needed to compensate these effec… more
Date: January 1, 1993
Creator: Ruggiero, Alessandro G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Monitoring production target thickness

Description: Pion and muon production targets at the Clinton P. Anderson Meson Physics Facility consist of rotating graphite wheels. The previous target thickness monitoring Procedure scanned the target across a reduced intensity beam to determine beam center. The fractional loss in current across the centered target gave a measure of target thickness. This procedure, however, required interruption of beam delivery to experiments and frequently indicated a different fractional loss than at normal beam curre… more
Date: January 1, 1993
Creator: Oothoudt, M.A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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On the high intensity aspects of AGS Booster proton operation

Description: Observations of high intensity effects on the proton performance of the AGS Booster are presented, including present operational limits and correction methods. The transverse emittances, optimum tune working points, damping of coherent transverse oscillations and correction of stopband resonances through third-order are discussed in addition to the observed tune spread due to space charge forces. The initial longitudinal phase space distribution, capture and acceleration parameters and measurem… more
Date: January 1, 1993
Creator: Reece, R. K.; Ahrens, L. A.; Bleser, E. J.; Brennan, J. M.; Gardner, C.; Glenn, J. W. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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[Epithermal neutron capture therapy]

Description: Development of a 4 mA, 2.5 MeV Tandem Cascade Accelerator (TCA) for the production of neutrons via the [sup 7]Li(p,n)[sup 7]Be nuclear reaction is currently nearing completion at SRL. The TCA is a tandem electrostatic accelerator which uses a high current negative ion source in conjunction with a high current solid state cascade multiplier power supply to provide a compact, low cost, proton accelerator capable of supplying multi-milliampere currents at several million electron volts. The inhere… more
Date: January 1, 1993
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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