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During the design of a cyclotron the time and attention dedicated to the injection and extraction of a beam usually overcome those devoted to the acceleration. However, the efficiency of the accelerating process largely contributes to the overall efficiency of the machine because the beam spends the most time in the accelerating region. A thorough and systematic study of the influence of beam parameters on the overall quality of acceleration is performed. The conditions for the optimal acceleration are determined and the method for defining the complete continuous sets of input parameters providing such acceleration is proposed. Index Terms--Acceleration efficiency, beam centering, cyclotrons, optimal acceleration, particle beam dynamics.

The article describes a medium-energy, injector-free synchrotron, which employs a strong focusing lattice for ion-beam guiding and hence is capable of accelerating ions of all the species. The synchrotron acts injector-free due to the synchronization of bunch circulation with the acceleration, which is commonly caused due to the energizing of the switching power supply by the trigger signal.

This Resource Letter provides a collection of resources for teaching and research in the field of particle beams and accelerators. I first attempt to give a brief introduction to the facilities, field, and community, and then turn to its literature and educational resources. I also try to include selected websites in the hope of helping the reader explore the web more extensively for specific items. [DOI: 10.1119/1.2221344]

The Tevatron is a proton anti-proton accelerator collider operating at the Fermi National Accelerator Laboratory. The machine is currently delivering beams for the CDF and DO experiments, which expect increasing luminosity until the conclusion of Run II planned for 2009. The Laboratory defined a plan for achieving higher luminosity, and one of the tasks is the upgrade of the accelerator's beam position monitor (BPM). The Tevatron was built during the early eighties and some of its control systems, including the BPMs, are still the original ones. This paper describes the front-end software of the Tevatron BPM upgrade, from the requirements to the implementation, and the underlying hardware setup. The design of the front-end software focuses on its modularity and reusability, allowing it to be applied to other Fermilab machines. Index Terms--Accelerator measurement systems, beam position monitor, particle beam measurements.

We describe a novel current accumulation algorithm for the three-dimensional self magnetic field calculation in a charged-particle beam optics code. The current source is a charged-particle beam represented by a collection of numerically-integrated current-carrying rays. We compute the magnetic vector potential using edge basis functions and the curl-curl formulation of the finite-element method. The current accumulation algorithm takes advantage of a novel particle tracker that happens to be ideal for this application. We show that our source vector is compatible with the singular finite-element matrix, even with modest numerical integration errors. Thus, a conjugate gradient matrix solver works well, with no need for additional gauge conditions. We confirmed this behavior in a series of numerical tests on a small problem with incomplete linear and quadratic basis functions on a variety of element shapes. Index Terms--Electron trajectory code, finite-element methods, gun code, magnetostatics, particle beam optics.

The DARHT-II linear-induction accelerator has been successfully operated at 1.2-1.3 kA and 12.5-12.7 MeV to demonstrate the production and acceleration of an electron beam. Beam pulse lengths for these experiments were varied from 0.5 [micro]s to 1.2 [micro]s full-width half-maximum. A low-frequency inductance-capacitance (LC) oscillation of diode voltage and current resulted in an oscillation of the beam position through interaction with an accidental (static) magnetic dipole in the diode region. There was no growth in the amplitude of this oscillation after propagating more than 44 m through the accelerator, and there was no loss of beam current that could be measured. The results of these initial experiments are presented in this paper. Index Terms--Accelerator, accelerator measurement systems, induction accelerators, particle beams, stability.

The spallation neutron source (SNS) is a next-generation high-intensity beam facility. The extraction kicker system is a high peak power, high average power, high-precision pulse-waveform, low beam impedance, and high repetition rate pulsed power system. It has been successfully designed and developed at Brookhaven National Laboratory, Upton, NY. The system consists of fourteen extraction magnet sections inside the ring vacuum chamber and fourteen identical high-voltage modulators located in the service building. The design features a Blumlein pulse-forming-network (PFN) based topology, a low beam impedance termination, a fast current switching thyratron, and low inductance capacitor banks. It has a maximum charging voltage of 50 kV, an open circuit output of 100 kV, and a designed maximum pulsed current output of 4 kA per modulator. The overall system output will reach multiple GW peak power with a 60 pulse/s repetition rate. A prototype modulator has been successfully built and tested well above the SNS requirement. The first batch of production modulators have passed all required tests at manufacture facility and delivered to Oak Ridge National Laboratory, Oak Ridge, TN, and the rest of the production units are under construction. The technical challenges and development results are presented in this paper. Index Terms--Accelerator power supplies, particle beam extraction, proton accelerators, pulse power systems.

A novel method for quantitative total protein determinations is presented. Total protein content is determined by particle beam/hollow cathode optical emission spectroscopy (PB/HC-OES) through monitoring of carbon atomic emission. The PB/HC-OES offers such advantages as ease of operation, exclusion of labor-intensive sample pretreatment processes, rapid analysis, high sensitivity, and low detection limit. The method could also be adapted to be integrated to current microfluidics devices. Parametric optimization for sample introduction, nebulization, desolvation, and hollow cathode source conditions is performed for the analysis of aqueous bovine serum albumin solutions. Response curves of C (I) 193.0-nm emission were obtained under the optimized conditions with both 10% HC1 and 100 [micro]g/mL KC1 added to the sample matrix as potential carriers. The detection limit for triplicate injections of bovine serum albumin standards was found to be on the single-nanogram level with 200-[micro]L injections. The addition of KC1 significantly improved the sensitivity, supporting the proposed 'carrier effect' of chloride salts in the particle transport process. Results obtained here suggest a range of applications for the use of the PB/HC-OES source for total protein determinations; emphasis here is future use in assessing protein quantification in microfluidic systems.

The envelope oscillations of a cold-fluid corkscrewing elliptic beam in a uniform-focusing magnetic field are studied. In particular, by linearizing the generalized beam envelope equations, the eigenmodes of small-amplitude envelope oscillations are calculated for a cold-fluid corkscrewing elliptic beam oscillating about its equilibrium. All of the eigenmodes are shown to be stable. Index Terms--Focusing, particle beam stability, space-charge-dominated.

Superconducting magnets for the proposed upgrade of GSI's accelerator facility are described and discussed.

A prototype HTS cryogenic current comparator is described and discussed.

Properties of high-field quadrupoles can be improved by means of corrective coils, pole-voids and high-performance steel.

Use of a superconducting magnet in a particle-beam delivery system for therapy of cancer (hadrontherapy) is discussed.

The magnet in the beam-line injection from the Separate Sector Cyclotron (SSC) to the Cooling Storage Ring (CSR) was chosen as the HIRFL-CSR (Heavy Ion Research Facility in Lanzhou - Cooling Storage Ring) project magnet fabrication's R&D magnet. An approach for obtaining good field homogeneity was tried in a C-type dipole prototype.

High-intensity, high-energy accelerators impost strict demands on injection/extraction septum magnets for a thin structure, large aperture and high-operating field. An opposite-field septum magnet system can provide a solution for realizing a thin septa or very high-field septum magnets.

A wide-aperture 90-degree bending magnet is described. The device is for use in the beam delivery system of the heavy-ion therapy facility developed at the GSI research center, Darmstadt, Germany.

The field of accelerators and beams (A&B) is one of today's fast changing technologies. Because university faculties have not been able to keep pace with the associated advancing knowledge, universities have not been able to play their traditional role of educating the scientists and engineers needed to sustain this technology for use in science, industry, commerce, and defense. This problem for A&B is described and addressed. The solution proposed, a type of 'distance' education, is the U.S. Particle Accelerator School (USPAS) created in the early 1980s. USPAS provides the universities with a means of serving the education needs of the institutions using A&B, primarily but not exclusively the national laboratories. The field of A&B is briefly summarized. The need for education outside the university framework, the raison d'etre for USPAS, the USPAS method, program structure, and curriculum, and particular USPAS-university connections are explained. The management of USPAS is analyzed, including its unique administrative structure, its institutional ties, and its operations, finance, marketing, and governmental relations. USPAS performance over the years is documented and a business assessment is made. Finally, there is a brief discussion of the future potential for this type of educational program, including possible extrapolation to new areas and/or different environments, in particular, its extra-government potential and its international possibilities.

This paper presents a formulation of a numerical integrator for charged particles. The original idea of the integrator scheme was already given several years ago. Main topics of this paper is reformulation of the integrator as the Lorentz group Lie algebra map and modifications for practical use. Two numerical simulation examples, trapped electron motion in cusp magnetic field and electron pendulum motion in the Free Electron Laser (FEL), show validity of this new formulation. Index terms - Particle beam, Integrator, Numerical analysis

Z-pinches are well-known plasma devices recently proposed as magnetic lenses. This focusing application requires an accurate modelling of the magnetic field distribution in the plasma discharge dynamics. It is a typical electromagnetic coupled problem, involving mechanical, thermal and circuital aspects, that have all to be properly modelled and coupled together. In this paper a model of the device, including energy balance and circuit coupling, is outlined, and its application to plasma discharges is discussed. Index terms - Magnetic fields, plasma pinch, numerical analysis, simulation, motion analysis, MHD, shock waves, particle beams.

The knowledge and the control of the magnetic field profile is of major importance in the application of plasma discharges as magnetic lenses for charged particles beams, because of the complex dynamics of the plasma. Since conventional field measurements are quite difficult for high current plasma discharges, we propose an inverse formulation for the identification of the field profile directly from the focusing data. The problem is shown to be ill-posed, in general; therefore a regularisation is needed. This is obtained, first, by means of a proper restriction of the observation space; second, by using an over determined data set, leading to a pseudo-inversion procedure. The numerical solution is illustrated, showing the procedure to be robust, at least for the practical applications range. In particular it is shown how the proposed method is effective in determining the amount of distortion of the field profile as compared to the reference linear one. Index terms - Magnetic fields, particle beams, optimization, inverse problems.

A design of a multipass optical cell is proposed. This design is based on the use of corner-cube retroreflectors arranged opposite to parallel axes, an incident beam that enters off the plane that contains the axes of the retroreflectors, and right-angle prisms to return to the cell the beam that left it after several reflections. This design allows the light beam to pass through the cell many times so that the beam paths fill the cell volume tightly and homogeneously. OCIS codes: 120.3180, 120.4570.

A theoretical procedure has been developed for the determination of internal and external electromagnetic fields that result from the interaction of a higher-order Gaussian beam with a homogeneous sphere. Specific calculations are performed for (1, 0), (0, 1), and (1, 1) mode Hermite-Gaussian beams and for doughnut mode beams of four different polarizations (radial, angular, arced, and helix). The effects of incident beam type on resonance excitation, and on the spatial distribution of the internal and near-surface electromagnetic fields, are examined. Key words: Higher-order Gaussian beams, laser-particle interactions, electromagnetic fields, spherical particle.

The localized model of the beam-shape coefficients for Gaussian beam-scattering theory by a spherical particle provides a great simplification in the numerical implementation of the theory. We derive an alternative form for the localized coefficients that is more convenient for computer computations and that provides physical insight into the details of the scattering process. We construct a FORTRAN program for Gaussian beam scattering with the localized model and compare its computer run time on a personal computer with that of a traditional Mie scattering program and with three other published methods for computing Gaussian beam scattering. We show that the analytical form of the beam-shape coefficients makes evident the fact that the excitation rate of morphology-dependent resonances is greatly enhanced for far off-axis incidence of the Gaussian beam.

Experimental calculations of a uniform collisonless charged-particle beam indicates its instability under the forces of electrostatic and internal pressure. Increase in mode number and magnitude of the forces enhances instability, which leads to an increase in parallel temperatures and widening of the density profile. These facts indicate limitations in focusing of the lens system.

The design and preliminary operating characteristics of a particle beam/hollow cathode atomic emission spectrometry (PB/HC-AES) device is described. By use of a high-efficiency thermal-concentric nebulization system coupled to a particle beam LC/MS interface, analyte particles originating in aqueous solution are introduced into a heated hollow cathode glow discharge for subsequent vaporization and excitation. The Thermabeam (Extrel Corp.) interface permits liquid introduction in either flow injection or chromatographic mode. Helium and argon are evaluated as discharge gases over a range of pressures and discharge currents, with He chosen as the most appropriate for subsequent analytical studies. Nebulization temperature, liquid (solvent) flow rate, and vaporization temperature are evaluated in order to determine their effects on analyte emission characteristics. Optimized sample introduction and He plasma operation conditions are employed to study the analytical characteristics of the PB/HC-AES system. Background equivalent concentrations (BECs) for Na and Cs (as nitrates) in aqueous solutions are 0.53 and 0.74 ppm, respectively. Subsequent studies of cesium at ppm levels in diluted (1000X) simulated nuclear waste solutions (5.0 M NaNO3 and 0.1 M KOH) indicated that the addition of excess chloride as a counterion, rather than nitrate, greatly enhances detectability. BEC values for Cs in aqueous solution were lowered by a factor of [approximately] 10, while for the diluted simulant the values were lowered by >100X, with detection limits in the latter found to be [approximately] 8 ppb.

Experimental studies using a 5-m-long periodic solenoid channel over a wide range of focussing conditions help verify the smooth-approximation theory for the effective radius of a space-charge dominated beam in an axisymmetric periodic focusing channel. Smooth-approximation theory results for an average beam radius -R over one period and the ratio R/R(max) in the beam envelope, taking into account the spherical aberration, agree with the experimental data. Spherical aberration effect is large only for focusing conditions with space-charge, sigma(0) < 60 degrees, and is negligible for sigma(0) > 600 degrees.

We present a quantum mechanical treatment of particle beam magnetic resonance and related experiments, in terms of static plane waves, applicable to experiments with oscillating fields. The results yield an alternate view of Larmor precession, showing it as a beating between different waves, and help to shed new light on several aspects of the problems discussed. We discuss magnetic resonance experiments with both the Rabi and Ramsey methods, neutron resonance spin echo and a neutron interferometer experiment.

In connection with the Japanese Hadron Facility (JHF) project, the development of new types of radiation-resistant magnet coils has been continued at KEK. One major program is the design and production of a mineral insulation cable (MIC) with a larger maximum current. We have already developed a 2000A-class MIC having a square-cross-section hollow conductor. A sample magnet coil was fabricated with this MIC. Tests of its stability and reliability are under progress. We are now planning to develop a 3000A-class MIC. The other program is R/D work on a completely inorganic wrapping insulation material which can be used like the usual type glass-fiber tape pre-impregnated with epoxy-resin. After tests of the mechanical strength and electric insulation of many combinations of tapes and bonds, we found a pure (99%>) alumina-fiber tape pre-impregnated with inorganic cement that is suitable for a magnet coil insulator after thermal curing.

The Fragment Separator is a device for producing and separating exotic nuclear beams. The exotic nuclei can be investigated directly, or the secondary beams can be injected into the storage-cooler ring, or delivered to targets in the experimental caves. The magnets of the spectrometer and the equipment used to measure the magnetic fields are described. Results of the measurements and operational experience with the laminated magnets are reported.

The dipole-sheet formalism can be used to describe both cylindrical current-sheet multipole magnets and cylindrical-bore magnets made up of permanent magnet blocks. For current sheets, the formalism provides a natural way of finding a finite set of turns that approximate a continuous distribution. The formalism is especially useful in accelerator applications where large-bore, short, high-field-quality magnets that are dominated by fringe fields are needed. A further advantage of the approach is that in systems with either open or cylindrically symmetric magnetic boundaries, analytical expressions for the three-dimensional fields that are suitable for rapid numerical evaluation can be derived. This development is described in some detail. Also, recent developments in higher-order particle-beam optics codes based on the formalism are described briefly.

Analytical solutions are presented for deflections beyond the elastic limit for prismatic and nonprismatic beams (beams with linearly varying depth) restrained and loaded in any way. The analytical solutions provide by differentiation the rotation, curvature, moment, and the shearing force. Simply supported and built-in beams with uniform cross section and with linear variations in depth symmetrically with respect to midspan, loaded at midspan, are analyzed; and the results are given in a dimensionless form. The displacement occurring just prior to the collapse mechanism is 2.243 of that occurring at the limit elastic behavior for simple and built-in uniform beams. For ratios between the minimum and the maximum depths of the beam less than 0.41, the collapse mechanism occurs with plastic hinges located at midspan and along the beam. Five elastoplastic behaviors for built-in beams with linearly varying depth are established, and the limit ratios between the maximum and the minimum depths of the beam separating these behaviors are determined.

Commercial radioisotope production using accelerated charged particles is a relatively new venture. As a result, various aspects of automated production facilities can be improved. The automated beam transport system described in this paper improves the operation of an industrial radioisotope production facility by incorporating features that enhance both the reliability of operation and the ease of maintenance in a radiation environment.

Developments in the study of short-lived nuclei are presented, particularly research that evolved with the development of nuclear beam facilities. These research explain some important processes in nuclear physics and astrophysics.

In this paper we demonstrate the successful interfacing of ion chromatography with particle beam mass spectrometry through the use of a membrane suppressor for continuous desalting. The microbore version of the membrane suppressor does not introduce significant peak broadening. The detection limit for six aromatic sulfonic acids in the full scan mode is better than 0.4 micron g injected on-column. The utility of a mixed-phase column, having both reversed-phase and ion-exchange capabilities, is also demonstrated in the chromatography of a hazardous waste sample. For the determination of anionic compounds in particular, the particle beam mass spectrometer is found to exhibit an analyte carryover phenomenon, except under the cleanest conditions. The contamination problem is found to be independent of the choice of column or the use or absence of a membrane suppressor.

An analytical model has helped in obtaining equilibrium quantities of interest from high-intensity charged particle beams such as the emittance, beam envelope and the number of beam halo particles. The results are particularized to the case of initially homogeneous beams, with azimuthal symmetry, and are focused by a constant magnetic field while confined in a linear channel.

The analysis of boundary conditions imposed by the infinite cathode emissivity and infinitely strong magnetic field has helped in determining the shape of the current density near the margin of the space charge. The implications for treating experimental measurements, design of high current devices, and particle beam extraction are discussed.

The accuracy of the perturbation model to predict the effect of scattering and absorbing inhomogeneities on photon migration has been investigated by comparisons with experimental and numerical results. Comparisons for scattering inhomogeneities showed that the model gives satisfactory results both for the intensity and for the temporal profile of the perturbation over a large range of values for the scattering properties of the defect. As for absorbing inhomogeneities, the model provides an excellent description for the temporal profile, but the results for the intensity are accurate only when the perturbation is small. For absorbing inhomogeneities an empirical model that has a significantly more extended application range has been proposed. The model is based on an expression for the time-resolved mean path length that detected photons have followed inside the inhomogeneity. The application range of the proposed model covers the values expected for the optical properties and for the volumes of inhomogeneities of practical interest for optical mammography. OCIS codes: 170.5280, 170.3830, 170.3880, 170.4580, 170.7050.