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ECR heavy-ion source for the LBL 88-inch cyclotron

Description: An Electron Cyclotron Resonance (ECR) heavy-ion source is under construction at the LBL 88-Inch Cyclotron. This source will produce very-high-charge-state heavy ions, such as 0/sup 8 +/ and Ar/sup 12 +/, which will increase cyclotron energies by a factor of 2-4, up to A = 80. It is a two-stage source using room-temperature coils, a permanent-magnet sextupole, and a 6-9 GHz microwave system. Design features include adjustable first-to-second-stage plasma coupling, a variable second-stage mirror ratio, high-conductance radial pumping of the second stage, and a beam-diagnostic system. A remotely movable extraction electrode will optimize extraction efficiency. The project includes construction of a transport line and improvements to the cyclotron axial-injection system. The construction period is expected to be two years.
Date: March 1, 1983
Creator: Clark, D.J.; Kalnins, J.G. & Lyneis, C.M.
Partner: UNT Libraries Government Documents Department

Improved alternating gradient transport and focusing of neutral molecules

Description: Polar molecules, in strong-field seeking states, can be transported and focused by an alternating sequence of electric field gradients that focus in one transverse direction while defocusing in the other. We show by calculation and numerical simulation, how one may greatly improve the alternating gradient transport and focusing of molecules. We use a new optimized multipole lens design, a FODO lattice beam transport line, and lenses to match the beam transport line to the beam source and the final focus. We derive analytic expressions for the potentials, fields, and gradients that may be used to design these lenses. We describe a simple lens optimization procedure and derive the equations of motion for tracking molecules through a beam transport line. As an example, we model a straight beamline that transports a 560 m/s jet-source beam of methyl fluoride molecules 15 m from its source and focuses it to 2 mm diameter. We calculate the beam transport line acceptance and transmission, for a beam with velocity spread, and estimate the transmitted intensity for specified source conditions. Possible applications are discussed.
Date: December 2, 2001
Creator: Kalnins, Juris; Lambertson, Glen & Gould, Harvey
Partner: UNT Libraries Government Documents Department

Bevalac external beamline optics

Description: This handbook is intended as an aid for tuning the external particle beam (EPB) lines at the Lawrence Berkeley Laboratory's Bevalac. The information contained within will be useful to the Bevalac's Main Control Room and experimenters alike. First, some general information is given concerning the EPB lines and beam optics. Next, each beam line is described in detail: schematics of the beam line components are shown, all the variables required to run a beam transport program are presented, beam envelopes are given with wire chamber pictures and magnet currents, focal points and magnifications. Some preliminary scaling factors are then presented which should aid in choosing a given EPB magnet's current for a given central Bevalac field. Finally, some tuning hints are suggested.
Date: April 1, 1987
Creator: Kalnins, J.G.; Krebs, G.F.; Tekawa, M.M. & Alonso, J.R.
Partner: UNT Libraries Government Documents Department

The production and use of radioactive nuclear beams at the Bevalac

Description: Using the fragmentation process, radioactive nuclear beams (RNB) are routinely produced at the Lawrence Berkeley Laboratory's Bevalac. Three beam lines are operational for production and transport of RNB: (1) a line for use in the radiotherapy treatment program (A {congruent} 20 amu), (2) a line for low mass (A {congruent} 20 amu) nuclear science studies and (3) a line for medium mass (A {congruent} 50 amu) nuclear science studies. A fourth beam line is under construction that will allow higher mass RNB (A {congruent} 100 amu) to be transmitted to the Bevalac's Heavy Ion Superconducting Spectrometer. Characteristics of RNB production and transport efficiency are described along with the RNB experimental program at the Bevalac.
Date: October 1, 1991
Creator: Krebs, G.F.; Alonso, J.R.; Feinberg, B. & Kalnins, J.G.
Partner: UNT Libraries Government Documents Department

Radioactive ion beams at the Bevalac: Greatly enhanced fragment separation for high energy beams

Description: Radioactive beams are routinely produced at the Bevalac by the fragmentation process. High energy beams (energies {approximately} 800 MeV/u) produce fragments with nearly the original beam momentum, forming a radioactive ion beam. A new beamline is being constructed which will provide resolution for ions approaching the mass 100 region, compared to the present mass 20 capability, by strongly increasing the dispersion and also increasing the beam size for easier tuning and more effective collimation. In addition, the angular acceptance has been more than doubled. Details of the design will be presented. 6 refs., 4 figs., 1 tab.
Date: September 1, 1990
Creator: Feinberg, B.; Kalnins, J.G. & Krebs, G.F.
Partner: UNT Libraries Government Documents Department

Design of a pulsed switching magnet for the Bevalac

Description: The design and construction of a water cooled, pulsed, laminated core dipole magnet which has recently been installed at the Bevalac is described. This new, energy efficient magnet was funded by the DOE In-House Energy Management Program. The magnet has been specifically designed for maximum efficiency in power utilization and has replaced two dc powered magnets in the Bevalac switchyard. It will reduce energy usage by 747 MWh/yr, and it provides the capability of pulse-to-pulse switching in 0.7 seconds between two major beamline channels serving the nuclear science and radiotherapy programs at the /Bevalac. A unique feature of this magnet is the core design which utilizes an external structure that remains integral with the core laminations after assembly. The structure provides for both torsional and longitudinal rigidity of the core while also facilitating the precision assembly and compression of the core laminations without the use of special assembly fixtures. 2 refs., 4 figs., 1 tab.
Date: March 1, 1989
Creator: Abbott, S.; Alonso, J.; Brown, J.; Kalnins, J.; Krebs, G. & Reimers, R.
Partner: UNT Libraries Government Documents Department

U.S. Department of Energy physical protection upgrades at the Latvian Academy of Sciences Nuclear Research Center, Latvia

Description: Approximately five years ago, the Safe, Secure Dismantlement program was started between the United States and countries of the Former Soviet Union (FSU). The purpose of the program is to accelerate progress toward reducing the risk of nuclear weapons proliferation, including such threats as theft, diversion, and unauthorized possession of nuclear materials. This would be accomplished by strengthening the material protection, control, and accounting systems within the FSU countries. This paper describes: the process involved, from initial contacting to project completion, for the physical protection upgrades now in place at the LNRC; the intervening activities; and a brief overview of the technical aspects of the upgrades.
Date: December 31, 1966
Creator: Haase, M.; Hine, C.; Robertson, C.; Soo Hoo, M. S.; Engling, E.; Lapenas, A. et al.
Partner: UNT Libraries Government Documents Department

Emittance at the superHILAC and the Bevalac transfer line

Description: The SuperHILAC (SHILAC) accelerator serves as a heavy-ion injector to the Lawrence Berkeley Laboratory's Bevalac via a 260 m transport line. Since the acceptance, and hence the final extracted beam intensity of the Bevalac is very sensitive to the emittance and dispersion of the beam at injection, a program was undertaken to accurately characterize these parameters under a variety of operating conditions. 7 figs.
Date: March 1, 1989
Creator: Krebs, G..F.; Kalnins, J.G.; Abinante, M.S.; Alonso, J.R.; Feinberg, B.; Fowler, K. et al.
Partner: UNT Libraries Government Documents Department

The Bevalac long flattop

Description: Until July of 1992, the maximum length of the Bevalac flattop was 2 seconds, limiting the beam spill to 1.5 seconds. The normal running condition was a 1.5 second flattop, with a 1.0 second beam spill. If we define the duty factor as the spill length (in time) divided by the synchrotron pulse length, that is, the percentage of time the Bevalac can deliver beam to experiments, the duty factor for the 1.5 second flattop ranged from 17% (at full field, i.e., 12575 G) to 25% (low field). The purpose of the Long Flattop Project was to increase the length of the flattop, thus increasing the duty factor of the machine, and its efficiency for experiments. This has been done, with resultant increase in the duty factor and experimental data rate. It is now possible to run with duty factor of about 80% for low fields, falling to about 60% at 10 kG, and 34% at full field. This report documents what was done, and its limitations. It should be noted that increasing the length of the beam spill is only possible if the source can produce more beam per pulse than is usable by the experimenter. Experimenters running at full intensity with a short flattop (1.5 seconds) cannot benefit from a longer flattop. This paper describe the changes that have been made to Bevalac systems to make the long flattop possible, the limits put on the length of the flattop by existing hardware, and the procedure for tuning for the long flattop.
Date: October 1, 1992
Creator: Celata, C.M.; Abbott, S.; Bennett, M.; Bordua, M.; Calvert, J.; Dwinell, R. et al.
Partner: UNT Libraries Government Documents Department