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Physics division annual report 1999

Description: This report summarizes the research performed in the past year in the Argonne Physics Division. The Division's programs include operation of ATLAS as a national heavy-ion user facility, nuclear structure and reaction research with beams of heavy ions, accelerator research and development especially in superconducting radio frequency technology, nuclear theory and medium energy nuclear physics. The Division took significant strides forward in its science and its initiatives for the future in the… more
Date: December 6, 2000
Creator: Thayer, K., ed. & Physics
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Modeling of an inductive adder kicker pulser for DARHT-II

Description: An all solid-state kicker pulser for a high current induction accelerator (the Dual-Axis Radiographic Hydrodynamic Test facility DARHT-2) has been designed and fabricated. This kicker pulser uses multiple solid state modulators stacked in an inductive-adder configuration. Each modulator is comprised of multiple metal-oxide-semiconductor field-effect transistors (MOSFETs) which quickly switch the energy storage capacitors across a magnetic induction core. Metglas is used as the core material to … more
Date: September 25, 2000
Creator: Wang, L.; Caporaso, G. J. & Cook, E. G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Spheromak formation studies in SSPX

Description: We present results from the Sustained Spheromak Physics Experiment (SSPX) at LLNL, which has been built to study energy confinement in spheromak plasmas sustained for up to 2 ms by coaxial DC helicity injection. Peak toroidal currents as high as 600kA have been obtained in the 1m dia. (0.23m minor radius) device using injection currents between 200-400kA; these currents generate edge poloidal fields in the range of 0.2-0.4T. The internal field and current profiles are inferred from edge field m… more
Date: September 29, 2000
Creator: Hill, D. N.; Bulmer, R. H.; Cohen, B. L.; Hooper, E. B.; LoDestro, L. L.; Mattor, N. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Ion storage ring measurements of dielectronic recombination for astrophysically relevant Feq+ ions

Description: Iron ions provide many valuable plasma diagnostics for cosmic plasmas. The accuracy of these diagnostics, however, often depends on an accurate understanding of the ionization structure of the emitting gas. Dielectronic recombination (DR) is the dominant electron-ion recombination mechanism for most iron ions in cosmic plasmas. Using the heavy-ion storage ring at the Max-Planck-Institute for Nuclear Physics in Heidelberg, Germany, we have measured the low temperature DR rates for Fe{sup q+} whe… more
Date: June 6, 2000
Creator: Savin, D. W.; Badnell, N. R.; Bartsch, T.; Brandau, C.; Chen, M. H.; Grieser, M. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Beam-Target Interaction Experiments for Bremsstrahlung Converter Applications

Description: The DARHT TI accelerator uses a pulsed high current electron beam and Eiremsstrahlung converter target to generate an intense x-ray source for radiography. For the past several years, we have been performing an investigation of the possible adverse effects of (1) backstreaming ion emission from the Bremsstrahlung converter target and (2) the interaction of the resultant plasma with the electron beam during subsequent pulses. These effects would manifest themselves in a static focusing system as… more
Date: September 28, 2000
Creator: Sampayan, S.; Caporaso, G.; Chen, Y. J.; Falabella, S.; Ho, D.; Houck, T. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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DARHT-II Downstream Beam Transport Beamline

Description: This paper describes the mechanical design of the downstream beam transport line for the second axis of the Dual Axis Radiographic Hydrodynamic Test (DARHT II) Facility. The DARHT-II project is a collaboration between LANL, LBNL and LLNL. DARHT II is a 20-MeV, 2000-Amperes, 2-{micro}sec linear induction accelerator designed to generate short bursts of x-rays for the purpose of radiographing dense objects. The downstream beam transport line is approximately 20-meter long region extending from th… more
Date: August 1, 2000
Creator: Westenskow, G A; Bertolini, L R; Duffy, P T & Paul, A C
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Pulse height spectrum measurement experiment for code benchmarking: first results

Description: The authors have completed a set of gamma-ray pulse height benchmark experiments using a high purity germanium detector to measure absolute counting rate spectra from {sup 60}Co, {sup 137}Cs and {sup 57}Co isotopic sources. The detector was carefully shielded and collimated so that the geometry of the system was completely known. The measured absolute pulse height spectrum counting rates as a function of detector position relative to the source are compared to energy deposit spectra calculated … more
Date: October 27, 2000
Creator: Sale, K E; Hall, J M & Brown, C M
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Proton reaction cross sections measured in the BNL/AGS E943 experiment

Description: We have measured proton reaction cross sections over a wide mass and energy range at the Brookhaven AGS accelerator. The samples were elemental Be, C, Al, Cu, W, and Pb; the measurements were carried out at ten incident proton kinetic energies in the range 0.54 to 7.8 GeV. The experiment was similar to an earlier experiment in the 200-550 MeV range by Renberg et al. The new results are in good agreement with those of Renberg et al. at the overlap point near 550 MeV. The combined results of the … more
Date: November 28, 2000
Creator: Dietrich, F S; Hartouni, E P; Schmid, G J; Soltz, R; Abfalterer, W P; Haight, R C et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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D0 General Support: The Use of Programmable Logic Controllers (PLCS) at D0

Description: With the exception of control of heating, ventilation, and air conditioning (HVAC) ventilation fans, and their shutdown in the case of smoke in the ducts, all implementations of Programmable Logic Controllers (PLCs) in Dzero have been made within the fundamental premise that no uncertified PLC apparatus shall be entrusted with the safety of equipment or personnel. Thus although PLCs are used to control and monitor all manner of intricate equipment, simple hardware interlocks and relief devices … more
Date: May 5, 2000
Creator: Hance, R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Spallation Neutron Source Beam Dump Radiation Shielding Analysis

Description: Preliminary shielding calculations were performed to establish the dimensions of the radiation shielding surrounding the three Spallation Neutron Source (SNS) beam stops. Steel shielding thicknesses were sized to give dose levels of 1, 2, and 5 mrem/h at the top of the shield, and, to provide enough shielding along the sides and bottom of the beam dump so that soil activation is not a problem. It was concluded that 144 in. of steel shielding is needed above the beam stop. The thickness of the c… more
Date: February 21, 2000
Creator: Johnson, J. O.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Computation of Normal Conducting and Superconducting Linear Accelerator (LINAC) Availabilities

Description: A brief study was conducted to roughly estimate the availability of a superconducting (SC) linear accelerator (LINAC) as compared to a normal conducting (NC) one. Potentially, SC radio frequency cavities have substantial reserve capability, which allows them to compensate for failed cavities, thus increasing the availability of the overall LINAC. In the initial SC design, there is a klystron and associated equipment (e.g., power supply) for every cavity of an SC LINAC. On the other hand, a sing… more
Date: July 11, 2000
Creator: Haire, M.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Investigations Into Accumulator 4-8 GHz Pickup Loop / Combiner Board Performance

Description: A set of pickup measurements performed in August of 1999 (see Pbar note 618) indicated problems with the pickup sensitivity for frequencies above {approx}4.8 GHz. This note describes the effort made to determine if the problems with system performance were due to the design of the 4-8 GHz circuit board.
Date: April 17, 2000
Creator: Vander Meuler, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Phasing of Debuncher Stochastic Cooling Transverse Systems

Description: With the higher frequency of the cooling systems in the Debuncher, a modified method of making transfer functions has been developed for transverse systems. (Measuring of the momentum systems is unchanged.) Speed in making the measurements is critical, as the beam tends to decelerate due to vacuum lifetime. In the 4-8 GHz band, the harmonics in the Debuncher are 6,700 to 13,400 times the revolution frequency. Every Hertz change in revolution frequency is multiplied by this harmonic number and b… more
Date: March 9, 2000
Creator: Pasquinelli, Ralph
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Dimensions and Measurements of Debuncher Band 3 and 4 Waveguide-Coax Launchers

Description: This note is a document about dimensions and measurement results of waveguide-coax launchers (Band 3 and 4) installed on the arrays in debuncher cooling upgrade. Shown in Figure 1 and 5 are schematic drawings of launchers (pick-up) in the cross section along the longitudinal direction (beam direction) of the arrays. The unit in these drawings is inch. Note: although there are upper band and lower band for pickup arrays, the launchers are the same to avoid possible confusion during installation.… more
Date: September 13, 2000
Creator: Sun, Ding
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Proposal for an Experiment to Measure Mixing, CP Violation and Rare Decays in Charm and Beauty Particle Decays at the Fermilab Collider - BTeV

Description: This proposal consists of five parts and two appendices. The first part provides a detailed physics justification for the BTe V experiment. The second part presents the considerations that drive the detector design, followed by a description of the detector itself. The third part summarizes our simulation results which demonstrate that the design does enable us to achieve our physics goals. The fourth part compares BTeV's physics reach to that of other experiments which will be active in B phys… more
Date: May 1, 2000
Creator: Kulyavtsev, A.; Procario, M.; Russ, J.; You, J.; Cumalat, J.; Appel, J. A. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Dimensions and Measurements of Debuncher Band 1 and 2 Waveguide-Coax Launchers (Final Version)

Description: This note is a document about dimensions and measurement results of waveguide-coax launchers (Band 1 and 2) installed on the arrays in debuncher cooling upgrade. Shown in Figure 1, 5, 8 and 12 are schematic drawings of launchers in the cross section along the longitudinal direction (beam direction) of the arrays. The unit in these drawings is inch. Note: although there are upper band and lower band for pickup arrays, the launchers are the same to avoid possible confusion during installation. RF… more
Date: February 15, 2000
Creator: Sun, Ding
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Lithium Irradiation Experiment

Description: The subject of tritium production in the Antiproton Source Collection lens was raised in the mid-1980s during the design phase of the pbar source. Interest in it has recurred during development of the proton lens and in recent investigations to determine the feasibility of liquid lithium collection lenses for the pbar source and a muon collider project. Calculations for tritium and beryllium 7 production on lithium suffer from a lack of information on medium and high energy cross section data. … more
Date: August 22, 2000
Creator: Leveling, A.F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Design and Simulation Results of Waveguide Bends Used in Debuncher Cooling System

Description: This note is a document about design and simulation results of waveguide bends installed with the arrays in debuncher cooling upgrade. The main feature of these bends is that they are not traditional mitered bends or round bends. Instead, a cylinder is placed in the corner area of the bend. The reason for this design is purely to overcome some practical problems: (1) since these bends are very close to the slotted foil which serves as part of the waveguide array, it is very difficult to make go… more
Date: September 13, 2000
Creator: Sun, Ding
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Measurements of Beam Momentum at the Stacking Energy of the Accumulator

Description: The momentum and orbit length of beam on the central and extraction orbits of the Antiproton Source Accumulator are calculated from measurements of revolution frequency and transverse beam position. This report gives the results of measurements made at the stacking energy before and after the 1998-99 Accumulator lattice upgrade. Before the lattice upgrade, the Accumulator central orbit length and momentum are measured to be: L{sub c} = 474.0433 {+-} 0.0025 m, p{sub c} = 8819.5 {+-} 4.1 MeV/c. A… more
Date: November 29, 2000
Creator: Werkema, Steve
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Debuncher Energy Mismatch

Description: During the December 1999 startup of antiproton stacking, a quick measurement of the Debuncher momentum aperture was made. The measurement was done by turning off and de-tuning the Debuncher bunch rotation cavities and observing the Debuncher 75 MHz longitudinal schottky signal of the circulating antiprotons as shown in Figure 1. The frequency at the center of the plot corresponds to the rotation frequency of the Debuncher RF cavities. (The schottky signal and the bunch rotation frequency occur … more
Date: January 25, 2000
Creator: McGinnis, Dave
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Extraction from the Accumulator With Rectangular Momentum Distributions

Description: Antiprotons for the Collider will be bunched in the Accumulator using a RF system (ARF4) that operates at a frequency that is four times the revolution frequency of the Accumulator. Four bunches can be extracted from the Accumulator in a single transfer. Since the TEVATRON will operate with 36 antiproton bunches, nine extractions from the Accumulator will be needed. During Run 1, the momentum distribution of the Accumulator core was shaped by the core cooling systems and was approximately gauss… more
Date: May 7, 2000
Creator: McGinnis, Dave
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Checking the Beam Energy Calculation from the June 14, 2000 $\psi^\prime$ Scan

Description: The Conclusions/Recommendations of this paper are: (1) It is very important to keep the orbit close to the reference orbit. (2) It is likely that BPMs are not perfectly calibrated. (3) The orbit length calculation with Quad Steering ON is more sensitive to errors in the BPM readout than with Quad Steering OFF. However, unless we are at the {psi}{prime}, Quad Steering should be ON. (4) Question: Should we use the BPM corrections derived from this scan? Answer: I don't know. I would prefer not to… more
Date: June 14, 2000
Creator: Werkema, Steve
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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