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Spin Rotation of Formalism for Spin Tracking

Description: The problem of which coefficients are adequate to correctly represent the spin rotation in vector spin tracking for polarized proton and deuteron beams in synchrotrons is here re-examined in the light of recent discussions. The main aim of this note is to show where some previous erroneous results originated and how to code spin rotation in a tracking code. Some analysis of a recent experiment is presented that confirm the correctness of the assumptions.
Date: February 1, 2008
Creator: Luccio,A.
Partner: UNT Libraries Government Documents Department

Influence of the deuteron energy on the testing volume of IFMIF and its impact on other parameters

Description: The influence of the energy of the deuteron beam on irradiation parameters of IFMIF is analyzed. The main purpose of this paper is to identify possible positive and negative impacts on irradiation parameters that an increase in the deuteron energy of the beam can cause. Several parameters of the facility, such as neutron generation rate, number of neutrons with energy above 20 MeV at the source and in the test assembly, volume with dpa rate above a threshold value, gas production, and gradient of the atomic displacement rate, are analyzed and conclusions are drawn based on the calculated values. It is shown that an increase in the deuteron energy to 40 MeV does not produce a significant negative impact for the elements analyzed, but instead is beneficial in producing nuclear responses more similar to a fusion environment than the lower deuteron energies.
Date: September 1, 1995
Creator: Gomes, I.C. & Smith, D.L.
Partner: UNT Libraries Government Documents Department

Plasma modified production of high-current, high-purity cw H{sup +}, D{sup +}, and H{sup -} beams from microwave-driven sources

Description: We have recently reported production of cw proton beams from magnetically confined microwave-driven sources, operating under nonresonant (non-ECR) conditions, with proton fractions > 0.95, the remaining fraction consisting of H{sub 2}{sup +} (0.05) with no H{sub 3}{sup +}. We achieve this by adding H{sub 2}O to the plasma at molecular concentrations of 1% and about 700 W 2.45 GHz RF power to the source. High-current (45 mA) high-power (45 kV) beams of >92% proton purity have been produced using this technique. Additional impurity ions O{sup +} at 4ppt and OH{sup +} and H{sub 2}O{sup +} at << 1ppt are produced. We report further progress using this technique and similar results achieved for cw D{sup +} beams with D{sub 2}O and H{sub 2}O additives. Finally, we report progress made in the direct extraction of cw H{sup -} beams from microwave-driven sources in terms of ion source surface material and confining magnetic field configurations. Mechanisms are discussed.
Date: October 1996
Creator: Spence, D.; Lykke, K. R. & McMichael, G. E.
Partner: UNT Libraries Government Documents Department

Spin Resonances for Stored Deuteron Beams in COSY. Vector Polarization. Tracking with Spink

Description: Results of measurements of vector and tensor polarization of a deuteron beam in the storage ring COSY have been published by the SPIN{at}COSY collaboration. In this experiment a RF Dipole was used that produced spin flip. The strength of the RFD-induced depolarizing resonance was calculated from the amount of spin flipping and the results shown in the figures of the cited paper. In this note we present the simulation of the experimental data (vector polarization) with the spin tracking code Spink.
Date: April 1, 2008
Creator: Luccio,A. & Lehrach, A.
Partner: UNT Libraries Government Documents Department

Analysis of intensity instability threshold at transition in RHIC.

Description: 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.
Partner: UNT Libraries Government Documents Department


Description: The assumptions used to derive the total neutron yield per detected alpha particle (from the D-T reaction) which were derived in an earlier report are reexamined in the light of additional experimental information. It is concluded that for an alpha counter at 90 deg to the incident beam direction the assumptions introduce practically no difficulties. Therefore, for precise monitoring in the absence of certain target information it is recommended that this configuration be used. For counters at angles different from 90 deg , nonuniformity of target loading contributes the most serious error to the computed yield. (auth)
Date: June 23, 1959
Creator: Benveniste, J.; Mitchell, A.C.; Schrader, C.D. & Zenger, J.H.
Partner: UNT Libraries Government Documents Department

Study of space charge-dominated beam bunching and some aspects of SSF linac designs

Description: This report is made up from works under the Agreement 1083P0015-35 between Los Alamos National Laboratory and Moscow Radiotechnical Institute. There are five report parts. In the 1-st, 2-nd, and 3-d parts works on SCD-beam dynamics understanding were continued. In the 4-th and 5-th parts two conceptual linac designs were considered: for deutron linac with energy of 40 MeV and for proton linac with energy 1 GeV. The both linacs have focusing by superconducting solenoids (SSF linacs). The 1 GeV proton CW linac design is an extension of the design from.
Date: December 31, 1995
Partner: UNT Libraries Government Documents Department

High-intensity polarized H-(proton), deuteron and 3He++ion source development at BNL.

Description: New techniques for the production of polarized electron, H{sup -} (proton), D (D+) and {sup 3}H{sup ++} ion beams are discussed. Feasibility studies of these techniques are in progress at BNL. An Optically Pumped Polarized H{sup -} Ion Source (OPPIS) delivers beam for polarization studies in RHIC. The polarized deuteron beam will be required for the deuteron Electron Dipole Moment (EDM) experiment, and the {sup 3}H{sup ++} ion beam is a part of the experimental program for the future eRHIC (Electron Ion) collider.
Date: June 23, 2008
Creator: Zelenski,A.
Partner: UNT Libraries Government Documents Department

Progress toward a microsecond duration, repetitively pulsed, intense- ion beam

Description: A number of intense ion beams applications are emerging requiring repetitive high-average-power beams. These applications include ablative deposition of thin films, rapid melt and resolidification for surface property enhancement, advanced diagnostic neutral beams for the next generation of Tokamaks, and intense pulsed-neutron sources. We are developing a 200-250 keV, 15 kA, 1 {mu}s duration, 1-30 Hz intense ion beam accelerator to address these applications.
Date: July 1, 1996
Creator: Davis, H.A.; Olson, J.C.; Reass, W.A.; Coates, D.M.; Hunt, J.W.; Schleinitz, H.M. et al.
Partner: UNT Libraries Government Documents Department

The Argonne ACWL, a potential accelerator-based neutron source for BNCT

Description: The CWDD (Continuous Wave Deuterium Demonstrator) accelerator was designed to accelerate 80 mA cw of D{sup {minus}} to 7.5 MeV. Most of the hardware for the first 2 MeV was installed at Argonne and major subsystems had been commissioned when program funding from the Ballistic Missile Defense Organization ended in October 1993. Renamed the Argonne Continuous Wave Linac (ACWL), we are proposing to complete it to accelerate either deuterons to 2 MeV or protons to 33.5 MeV. Equipped with a beryllium or other light-element target, it would make a potent source of neutrons (on the order of 10{sup 13} n/s) for BNCT and/or neutron radiography. Project status and proposals for turning ACWL into a neutron source are reviewed, including the results of a computational study that was carried out to design a target/moderator to produce an epithermal neutron beam for BNCT.
Date: February 1, 1995
Creator: McMichael, G.E.; Yule, T.J. & Zhou, X.L.
Partner: UNT Libraries Government Documents Department

Overview of the IFMIF test cell design

Description: The Conceptual Design Activity (CDA) for the International Fusion Materials Irradiation Facility (IFMIF) has entered its second and final year, and an outline design has been developed. Initial evaluations of the potential of this high flux, high intensity D-Li source have shown that the main materials testing needs can be fulfilled. According to these needs, Vertical Test Assemblies will accommodate test modules for the high flux (0.5 liter, 20 dpa/a, 250-1000 C), the medium flux (6 liter, 1-20 dpa/a, 250-1000 C), the low flux (7.5 liter, 0.1-1 dpa/a), and the very low flux (> 100 liter, 0.01-0.1 dpa/a) regions. Detailed test matrices have been defined for the high and medium flux regions, showing that on the basis of small specimen test technologies, a database for an engineering design of an advanced fusion reactor (DEMO) can be established for a variety of structural materials and ceramic breeders. The design concepts for the Test Cell, including test assemblies, remote handling equipment and Hot Cell Facilities with capacity for investigating all irradiation specimens at the IFMIF site are described.
Date: October 1, 1996
Creator: Moeslang, A.; Daum, E.; Haines, J.R.; Williams, D.M.; Jitsukawa, S.; Noda, K. et al.
Partner: UNT Libraries Government Documents Department

IFMIF accelerator conceptual design activities

Description: A Conceptual Design Evaluation (CDE) for the International Fusion Materials Irradiation Facility (IFMIF) began in 1997 and will be completed in 1998, as an international program of the IEA involving the European Community, Japan, Russia and the United States. The IFMIF accelerator system, comprising two 125 mA, 40 MeV deuterium accelerators operating at 175 MHz, is a key element of the IFMIF facility. The objectives and accomplishments of the CDE accelerator studies are outlined.
Date: December 31, 1998
Creator: Jameson, R.A.; Lagniel, J.M.; Sugimoto, M.; Kein, H.; Piaszczyk, C. & Tiplyakov, V.
Partner: UNT Libraries Government Documents Department

Neutron tube design study for boron neutron capture therapy application

Description: Radio-frequency (RF) driven ion sources are being developed in Lawrence Berkeley National Laboratory (LBNL) for sealed-accelerator-tube neutron generator application. By using a 5-cm-diameter RF-driven multicusp source H{sup +} yields over 95% have been achieved. These experimental findings will enable one to develop compact neutron generators based on the D-D or D-T fusion reactions. In this new neutron generator, the ion source, the accelerator and the target are all housed in a sealed metal container without external pumping. Recent moderator design simulation studies have shown that 14 MeV neutrons could be moderated to therapeutically useful energy ranges for boron neutron capture therapy (BNCT). The dose near the center of the brain with optimized moderators is about 65% higher than the dose obtained from a typical neutron spectrum produced by the Brookhaven Medical Research Reactor (BMRR), and is comparable to the dose obtained by other accelerator-based neutron sources. With a 120 keV and 1 A deuteron beam, a treatment time of {approx}35 minutes is estimated for BNCT.
Date: May 6, 1999
Creator: Verbeke, J.M.; Lee, Y.; Leung, K.N.; Vujic, J.; Williams, M.D.; Wu, L.K. et al.
Partner: UNT Libraries Government Documents Department

Use of molybdenum ion source electrodes at RTNS-II

Description: Reports are reported for an ongoing effort to optimize D+ beam production by the MATS-III ion source used at RTNS-II. The three seven-aperture electrodes, originally consisting of water-cooled copper, have now been tested using uncooled molybdenum and with water cooling on the second (decel) electrode only. Details of the change, the results of the testing, and the benefits in operation, performance and cost are given.
Date: September 29, 1986
Creator: Massoletti, D.J.; Harter, G.A. & Heikkinen, D.W.
Partner: UNT Libraries Government Documents Department

Medical and Health Divisions quarterly report, January, February, March 1948

Description: This quarterly progress report describes four programs namely (1) The Metabolic Properties of Plutonium and Allied Materials (2) Biological studies of radiation effects, (3) Biological effects of radiation from external and internal sources, and (4) Health Physics and Chemistry. Progress for each program has been separately indexed and abstracted for the database.
Date: May 24, 1948
Partner: UNT Libraries Government Documents Department

High energy polarized deuterons at the Argonne National Laboratory zero gradient synchrotron

Description: Modifications made on the ZGS to allow the acceleration of polarized deuterons and the operational experiences with the first production run with this beam are described.
Date: January 1, 1979
Creator: Parker, E.F.; Brandeberry, F.E.; Crosbie, E.A.; Knott, M.J.; Potts, C.W.; Ratner, L.C. et al.
Partner: UNT Libraries Government Documents Department

Development of niobium spoke cavities for a superconducting light-ion Linac.

Description: This paper reports the development of 350 MHz niobium superconducting cavities for the velocity range 0.2&lt; v/c &lt;0.6. Such cavities could be used to form a linac of exceptional flexibility, capable of efficiently accelerating beams of either protons, deuterons, or any of a wide range of light ions, at intensities sufficient for a production beam for a radioactive beam facility. Results of numerical modeling for several resonator geometries are presented. The design and construction status of prototype niobium cavities is discussed.
Date: November 18, 1998
Creator: Shepard, K. W.
Partner: UNT Libraries Government Documents Department


Description: Previous computations of cross sections for the D-D and D-T reactions were dependent on the knowledge of the energy loss of deuterons and tritons in D{sub 2}O ice targets. Recent Published experimental data on the energy loss dE/dx of protons in H{sub 2} and O{sub 2} have been sufficiently consistent to correct the results of the measurements of Bretscher, French and Sidel (Phys. Rev. 73, 815 (1948) and 75, 1154 (1949). Without describing the methods used to obtain the new data, the author uses the results of the dE/dx measurements to correct the cross sections of Bretscher et al. A simple correction factor is given, and the corrected values are tabulated for the D-D and D-T reactions. The Gamow formula, modified by a resonance factor, is applied to the revised data, and a good fit to the theoretical slope is obtained.
Date: January 1, 1952
Creator: Cook, C.J.; Jones, E. & Jorgensen, T.
Partner: UNT Libraries Government Documents Department


Description: The ''absolute'' containment of ions in the DCX magnetic mirror field resulting from the cylindrical symmetry of the field is discussed. The regions of confine;, ment in space and momentum are plotted for 300-kev deuterons. (auth)
Date: June 15, 1959
Creator: Fowler, T K & Rankin, M
Partner: UNT Libraries Government Documents Department

Reactor applications of two-component tokamak plasmas

Description: The physics of two-energy-component toroidal plasmas (TCT) is reviewed. Energy ''breakeven'' using the TCT mode (deuteron beams on a triton-target plasma) can be attained at much smaller ntau and temperature than in thermal plasma operation. This result reflects the fact that the fusion power density in a TCT can be much larger than in a thermal DT plasma of the same pressure. The large fusion power density (i.e., large neutron flux) of a TCT may find practical use in a number of applications. (auth)
Date: October 1, 1975
Creator: Tenney, F.H.
Partner: UNT Libraries Government Documents Department


Description: Possible experiments that could be performed at the Brookhaven alternating gradient synchrotron using highenergy deuterons and heavier nuclei are reviewed. Particular attention is given to production of high-energy neutrons by stripping. A brief analysis of changes needed to accelerate heavier nuclei reveals such modifications would not be prohibitive. (D.C.W.)
Date: December 18, 1962
Creator: Courant, E.D.
Partner: UNT Libraries Government Documents Department