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Fourier transform ion cyclotron resonance laser microprobe mass spectrometry (FTICR LMMS) uses focused laser irradiation of solids with a spot of 5 [micro]m and a FTICR mass analyzer for local analysis with high mass resolution. A new ion source design has been developed to improve the extraction and transfer of ions generated in an external laser microprobe source. Calculations predicted trapping of ions initially emitted with angles up to 40[degrees] and 60[degrees] from the surface and from a distance of 1 mm above the sample, respectively. The analytical performances of the method have been verified on two sets of test samples. First, detection of chemisorbed benzotriazole on copper, average of two monolayers, has been shown with less sample consumption than typically required in static secondary ion mass spectrometry with a time-of-flight analyzer. Second, experiments on a thermal plate for offset printing have shown the feasibility of analysis and quantification of dyes embedded in a polymer matrix.

The advent of ultra-high-resolution mass spectrometry has revolutionized the ability of aquatic biogeochemists to examine molecular-level components of complex mixtures of organic matter. The ability to accurately assess the chemical composition, elemental formulas, or both of detected compounds is critical to these studies. Here we build on previous work that uses functional group relationships between compounds to extend elemental formulas of low molecular weight compounds to those of higher molecular weight. We propose an automated compound identification algorithm (CIA) for the analysis of ultra-high-resolution mass spectra of natural organic matter acquired by electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry. This approach is benchmarked with synthetic data sets of compounds cited in the literature. The sensitivity of our results is examined for different sources of error, and CIA is applied to two previously published data sets. We find that CIA works well for data sets with high mass accuracy (< 1 ppm) and can accurately determine the elemental formulas for > 95% of all compounds composed of C, H, O, and N. Data with lower mass accuracy must be accompanied with additional knowledge of chemical structure, composition, or both in order to yield accurate elemental formulas.

Measurements of the electron temperature radial profile [T.sub.e](r) have been performed on the Tokamak Chauffage Alfven Bresilien tokamak with high radial resolution, using an electron cyclotron emission radiometer. The temperature profile shows distinct peculiarities in discrete radial regions which can be associated with the presence of magnetic islands. A method is proposed here to determine the radial positions and widths of the magnetic islands based upon measurement of the Fitzpatrick kind, not completely flattened, radial profile of the electron temperature [T.sub.e](r). In combination with other well-known methods, the suggested methods can give additional possibilities for comparing experimental and theoretical results in the study of magnetic islands. Index Terms--Island width, magnetic island, radiometry, temperature profile, Tokamak.

An attempt is made to show that the saddle form of CTV (and other peripherally hexa-substituted TBCN) can be obtained by rapidly quenching a hot solution or the high-temperature melt to below room temperature. The saddle form of CTV was quantitatively separated from the quenched material by column chromatography.

Electron cyclotron emission (ECE) diagnostics have been developed in the large helical device (LHD). The ECE is transmitted over 80 m from the antenna to the spectrometer with the corrugated waveguide system, which has a low transmission loss (~30%). The polarization of ECE is identical for all frequencies, while the field angle varies from -40[degrees] to +30[degrees] on the ECE sight line. The ECE temperature measured by the Michelson, which is calibrated with a hot source, agrees well with Thomson scattering measurement in a wide range of the electron density. Magnetic island formation is investigated using the electron temperature profile measured with the Michelson. The radiometer is cross-calibrated to the Michelson and is employed for the study of fast phenomena, such as the sawtooth oscillation. Besides the normal ECE, tangential ECE is investigated in LHD in order to explore the potential of ECE diagnostics. Index Terms--Diagnostics, electron cyclotron emission (ECE), large helical device (LHD), microwave, plasma, temperature.

The operation of gyrodevices at cyclotron harmonics is very attractive because of the possibility to reduce the magnetic field requirement by s times, where s is the cyclotron harmonic number. In recent years, two methods of harmonic operation in multistage gyroamplifiers have been actively studied: operation at a given harmonic in all stages and operation in the frequency-multiplying regime when the input stage operates at a lower harmonic than the output one. The present paper is aimed at making a comparative analysis of these two schemes of operation. To do this, a simple analytical method is developed, which allows one to qualitatively describe saturation effects in both schemes and compare such performance characteristics as the efficiency, gain, and bandwidth in both schemes. The results are of interest for evaluating the pros and cons of both schemes. Index Terms--Cyclotron harmonics, frequency multiplication, gyroamplifiers, gyrotrons.

A low-pressure methane plasma is characterized and the results are compared with those obtained theoretically by considering the steady-state kinetics of the chemical processes present in a low-pressure plasma reactor, in order to elucidate the dominant reaction channels responsible for generation of the active precursors required for film growth. Mass spectrometry measurements of the gas phase indicate little variation in the plasma chemistry with increasing electron temperature.

Quench characteristics of the superconducting main coils of the RIKEN Superconducting Ring Cyclotron (SRC) are studied.

A superconducting magnet that will be used as a sweeprr magnet for nuclear physics experiemnts is described. The device is being constructed by the National High Magnetic Field Laboratory (NHMFL), Florida State University, Talahassee, FL, for use at the National Superconducting Cyclotron Lab (NSCL), Minchigan State University, East Lansing, MI.

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.

A K2500 superconducting ring cyclotron is being built at RIKEN (Institute of Physical and Chemical Research, Hirosawa, Wako, Japan) to function as an energy booster for the existing K540 ring cyclotron. The design is described, and the status of the work is reported.

Special designs that use iron efficiently have been devised for powerful and compact normal-conducting magnetic channels involving the injection and extraction systems of the RIKEN (the Institute of Physical and Chemical Research, Wako, Saitama, Japan) Superconducting Ring Cyclotron (SRC).

Research is presented describing a superconducting bending magnet for beam injection that is being used in the construction at RIKEN of a K2500 superconducting ring cyclotron with six sectors. The ring cyclotron will be used as an energy booster for RIKEN's existing K540 ring cyclotron.

Electron cyclotron resonance heating (ECRH) plays a key role in stellarator research, because it provides net current free plasma start up and heating toward reactor relevant plasma parameters. ECRH was extensively used and investigated in the stellarator experiments at IPP Garching, i.e., the W7-A and the W7-AS stellarators. These experiments provide a solid physics and technological basis for the 10 MW, CW ECRH system, which is under construction for the superconducting next step stellarator W7-X and will become operational in 2005. We briefly describe some of the major stellarator specific physics results on ECRH and electron cyclotron (EC)-current drive from W7A and W7-AS. The scientific goals and the design of W7-X are outlined together with the demands for the ECRH system, which is the main heating system in the first stage of the experiment. The present status of the ECRH engineering design including the gyrotrons, all auxiliary systems, the transmission line, and the launching system are presented. Index Terms - Current drive, electron cyclotron resonance heating, gyrotron, magnetic confinement fusion, millimeter waves, stellarator.

A theoretical and experimental study was conducted to analyze the ionic motion in a cylindrical ion cyclotron resonance cell. The ionic cyclotron motion was coupled with a circular drift motion in the plane perpendicular to the magnetic field. Experimental results indicated that the effective cyclotron frequency was correlated with the effects of the Coriolis and centrifugal accelerations resulting from the circular drift motion.

Cyclotron wave amplifiers were invented in both the United States and Russia in the late 1950's. While work in the United States was dropped in favor of solid state amplifiers, their development and use continues in Russia. This paper develops the basic theory of these amplifiers for Western scientists and engineers, specifies the performance of several sample commercially produced items, and compares performance of these devices with theory. Applications of devices to real world radar systems and the resulting advantages are briefly discussed. Index Terms - Cyclotron wave amplifiers, low noise amplifiers, parametric amplifiers.

Cyclotron wave amplifiers at the harmonics of the electron cyclotron frequency are investigated. Since the waves on the beam are electrostatic, harmonics are strongly excited in nonrelativistic beams if they are rotating rather than filamentary. These modes at the harmonics can couple to input Cuccia couplers, and pump fields which drive parametric amplification, in very much the same way as they do on filamentary beams at the cyclotron frequency. Harmonic cyclotron wave amplifiers have the possibility of giving rise to a new class of devices at millimeter wave frequencies. Index Terms - Cyclotron harmonic electrostatic amplifier, cyclotron wave input amplifier, electrostatic amplifier, harmonic cyclotron wave input amplifier.

ITER, the International Thermonuclear Experimental Reactor, proposes to use electron cyclotron technology on an unprecedented scale. ECRF (electron cyclotron range of frequencies) will be used for start-up, heating, noninductive on- and off-axis current drive, and wall conditioning. Advanced gyrotron sources will be needed in order to fulfill the unique requirements imposed by these applications. Consequently, an international R&D program has been undertaken to develop 170 GHz, CW, 1 MW, [approximately]50% efficient tubes. The rationale for the R&D program is presented and design issues relating to the efficient generation, transmission, and delivery to the plasma of over 50 MW of ECRF power are discussed.

Phase-locking in a 34.5-GHz special complex cavity gyrotron oscillator operating at the second harmonic of the electron cyclotron frequency was studied. Injection of the locking power was made via a quasi-optical circulator connected to the gyrotron output. Locking bandwidth was measured by comparing the phase of the injection signal and output signal using a balanced mixer. Locking was observed with input power level as low as 40 dB below the gyrotron output power. The locking bandwidth is, however, narrower than in gyrotrons operating at the fundamental cyclotron frequency which may be attributed to the longer resonant cavity in the second harmonic gyrotron and the corresponding larger value of external quality factor. The measurements are roughly in agreement with predictions of Adler's phase-locking equation which is given for our system in terms of powers propagating in the output waveguide toward and away from the gyrotron cavity.

Using the Laplace transformation, the kinetic theory of the high-relativistic electron cyclotron maser having a novel open-resonator - the axisymmetrical quasioptical cavity of oblique rotation at arbitrary angle (AQCORAA), is carried out within the framework of the linearized Vlasov-Maxwell equations. The beam-wave interaction power, starting current and frequency shift have been derived and numerically calculated. The influence of rotating angle on beam-wave interaction is also studied. A series of important conclusions obtained in this paper reveal the characters of this novel quasioptical electron cyclotron maser.

Fluid dynamical treatment in slow wave cyclotrons helps formulate a linear theory for the slow wave cyclotron interaction in a folded rectangular waveguide containing a H-plane bend. The H-plane bend structure is capable of generating a high power broad band radiation. The linear theory indicates a gain between 2.0 and 2.5 dB cm and 20-25% bandwidth for cold beams.

A new superconducting extraction magnet system EMC2, has recently been installed in the AGOR cyclotron. It consists of two almost identical and slightly bent modules to accommodate the curved extraction beam. The coil system of each module consists of three coils located symmetrically around the median-plane, providing a main dipole field, a gradient field and a dipole correction field. The coil system is indirectly cooled by means of liquid helium flowing through channels located in the upper and lower part of both modules. In order to reduce the dissipation in the 4 K region due to beam losses, a 20 K radiation shield has been installed. Positioning of the extraction system to select a certain beam trajectory is provided by a guiding and feed-through system. This paper deals with the design and manufacturing of the superconducting and cryogenic parts of the EMC2 extraction system and the results of a successful test are presented.

A model has been developed for the rapid but accurate calculation of the static magnetic field in the Chalk River cyclotron. The field is expressed in terms of elementary functions which can be handled efficiently in differential-algebra trajectory integrations. Maxwell's equations are satisfied exactly. Each of seven subdivisions of the superconducting coils is treated by a moment expansion about a central circle. Each pole is modeled as a uniformly magnetized semi-infinite prism. Monopoles and dipoles at the vertices of the polygonal pole faces correct for departures from the true pole shape. Uniform distributions of dipole strength along the edges of the pole-face polygons correct for the local inappropriateness of the assumption of uniform magnetization. The contributions of the yoke and of other relatively distant parts of the structure to the field in the region of particle acceleration are represented by low-order polynomials. Some of the source parameters are obtained by fitting to the measured values of [B.sub.z] in the horizontal plane of symmetry.

A three-dimensional analytic model of the magnetic field for the TASCC cyclotron that satisfies Maxwell's equations exactly has been constructed for use with the new differential-algebra orbit-dynamics code. The model includes: 1) the superconducting coils; 2) the saturated iron poles; 3) the partially saturated yoke; 4) the saturated-iron trim rods. Lines of dipole density along the edges of the hills account for the non-uniformities and edge effects and along with three yoke constants constitute the only free parameters.

Effects of a magnetic field collimation on ion behavior in the downstream region of an electron cyclotron resonance (ECR) plasma device are clarified experimentally using a directional ion energy analyzer. The drift energy and its spread of the ion beam observed in the downstream region decrease and the beam temperature increases with the collimating magnetic flux density. Then, the ion temperature measured perpendicular to the axis of the plasma stream slightly decreases. The ion beam is found to be almost parallel to the magnetic field lines, that is, the beam tends to be collimated.

Several discrete frequencies are generated by GYROTRON V at millimeter wavelengths by an operation at the base of electron cyclotron frequency. Frequency range can be extrapolated up to the submillimeter wavelength region by second harmonic operation. Designing of resonant cavity with small radius produces a reduction in the nearly strong fundamental force. GYROTRON V always functions at very low currents, and generates power over a wide range of frequencies.

On the spot x-ray photoelectron spectroscopy, high-resolution cross-sectional transmission electron microscopy and atomic force microscopy are used in the determination of electron cyclotron resonance plasma evacuation of (100)Si surfaces. The (100)Si surfaces with low energy Ne, Ar and Xe ions are experimented to measure single surface and modulated optical reflectance. There is a decrease in ion energy for all ions when there is a reduction in oxygen concentration. Ion mass is inversely proportional to noble gas concentration.

Physicists Ernest Lawrence and Stanley Livingston emphasized the significance of cyclotrons for studies of the atomic nucleus. Improvements in the basic theory and subsequent research have allowed the cyclotron to become a critical medical equipment for treating human illnesses such as cancer.

Research involving design of a flux-coupled stack of 800 MeV isochronous cyclotrons is described. It is being designed for accelerator-driven thorium-cycle fission power.

Electron cyclotron resonance plasma cleaning and its effects on contact resistance between superconducting Nb and electron gas in InxGa1-xAs/InP heterostructures, is examined.

The story of World War II project dedicated to electromagnetically separating uranium-235 from uranium-238 is described by a scientist participating in the project. The development and use of the 'calutron' to produce enriched uranium for the first atomic bomb that was used in warfare, and then to produce the full spectrum of separated uranium isotopes for uses in peacetime is discussed.

Timothy Koeth, a sophomore in physics built a 12-inch cyclotron. The stories behind every aspect of building the cyclotron are mentioned.

To prepare a variety of novel cyclotriphosphazene-based ligand systems with N and O donor sets, a straightforward solvent-free methodology is developed. With selected ligand constructs, a variety of metal complexes are synthesized.

The development of ruthenium-catalyzed intramolecular alkyne cyclotrimerizations of diynes and triynes is presented. It is concluded that the resulting ruthenabicyclo[3.2.0]-heptatriene intermediate produces competitive [2 + 2 + 2] cyclotrimerization products.

A study was conducted to investigate the enhancement of magneto-optic polar Kerr rotation over a broad range of optical frequencies by appropriate coupling of omega and omega(sub c), for fixed omega(sub p). The result found higher omega(sub p) values in higher Kerr rotation.

The electron cyclotron wave current startup as a scheme to initiate ohmic discharges has been investigated with two circuits of open and shorted primary winding of transformer in the CT-6B tokamak. A diode shorted circuit is proposed for connection with ohmic discharges. Two gyrotron systems operated at different frequencies were used as the wave sources. The experimental results indicate that approximately equivalent transformer flux saving and reduction of starting voltage are achieved in the initial phase of the ohmic discharges for both circuits. An estimation of plasma resistance for the open circuit shows that no obvious anomalous resistance of the wave started plasma is observed. Index Terms--Current startup, electron cyclotron wave, ohmic discharge, tokamak.

By taking advantage of recent developments in millimeter wave imaging technology, an electron cyclotron emission imaging (ECEI) instrument, capable of simultaneously measuring 128 channels of localized electron temperature over a two-dimensional (2-D) map in the poloidal plane, has been developed for the TEXTOR tokamak. Data from the new instrument, detailing the magnetohydrodynamic (MHD) activity associated with a sawtooth crash, is presented. Index Terms--Electron cyclotron emission, microwave diagnostics, sawtooth instability.

A path-sum approach, based on Gaussian short-time propagators, is used to solve a two-dimensional Fokker-Planck model of the electron kinetics during electron--cyclotron current drive of tokamak plasmas, in the limiting case where the RF quasi-linear diffusion coefficient is very large. Index Terms--Current drive, electron--cyclotron wave, Fokker-Planck equation, Gaussian short-time propagators, tokamaks.

ABSTRACT: Positron emission tomography (PET) can probe biochemical pathways in vivo and can provide quantitative data; for that purpose, tracers labeled with positron-emitting radioisotopes are essential. This report describes the tracers that are being used or that may have future use, their production by cyclotrons, and other needed resources for PET imaging. Current routine and automated methods for convenient production of labeled compounds, coupled with simple computer-controlled accelerators, can support the creation of clinical PET centers in any large medical institution, obviating the need for in-depth research teams. An alternate approach involves the development of regional centers that provide in-house service and that supply fluorine 18- and carbon 11-labeled compounds to nearby hospitals with PET machines.

S Peil and G. Gabrielse have studied the fundamental quantum limit of the cyclotron motion of a single electron isolated from its surroundings. Gabrielse and colleagues developed a cylindrical Penning trap which reduces spontaneous emission by a factor of 140. The ability to control the cyclotron motion provides increased accuracy when measuring the electron magnetic moment.

The propagation of electromagnetic ion cyclotron waves as launched by an antenna of small transverse scale has been studied in a laboratory plasma. Effects of the finite perpendicular size of the plasma column on the wave magnetic field pattern are observed, and their analysis is aided by visualizing the wave fields in three dimensions. Index Terms - Electromagnetic propagation in plasma media, plasma loaded waveguides, plasma waves.

The characterization of cellular proteomes is important for understanding biochemical processes ranging from cell differentiation to cancer development. In one highly promising approach, whole protein extracts or fractions are digested (e.g., with trypsin) and injected into a packed capillary column for subsequent separation. The separated peptides are then introduced on-line to an electrospray ionization source of a Fourier transform ion cyclotron resonance (FTICR) mass spectrometer for the detection of peptide accurate mass tags that serve as biomarkers for their parent proteins. In this work, we report the use of data-dependent selective external ion ejection in conjunction with FTICR and on-line capillary LC separations for the enhanced characterization of peptide mixtures and a yeast extract proteome. The number of peptides identified in an LC-FTICR analysis of a yeast proteome digest employing data-dependent rf-only dipolar ejection of the most abundant ion species prior to ion accumulation was 40% higher than that detected in a separate LC-FTICR analysis using conventional nonselective ion accumulation.