The neoclassical radial electric fields in a tokamak are calculated for the shifted Maxwellian distribution function by using a δf Monte Carlo particle simulation code ”FORTEC-FSM”. The calculation results agree well with the analytical estimations. The present method will be useful for the determination of the neoclassical radial electric field in tokamak plasmas with input momentum or torque by, e.g., NBI heating.

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A linac is proposed in which a laser first excites plasmons along the inner surface of a metallic acceleration tube. The potential of the plasmon oscillation then accelerates electron beams. It features small beam size and good conversion efficiency from laser intensity to acceleration gradient.

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In the design of the International Thermonuclear Experimental Reactor (ITER), a forced flow cooled, Cable-In-Conduit Conductor (CICC) is selected for its magnet system because of its superior performance in withstanding voltage (>10kV) and, more importantly, its mechanical stiffness against large electromagnetic forces. The CICC consists of about 1,000 superconducting strands enclosed in a steel jacket, and due to this configuration, the CICC exhibits a characteristic electromagnetic phenomena which can be a cause of the instability of a conductor. Extensive studies were performed, especially on ac losses, stability, and current imbalance among the strands in order to understand the phenomena and to provide a design basis for CICC to be used in large superconducting magnets. This paper describes the work on developing the CICC including analytic studies regarding the realization of fusion magnets.

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In this paper, the use of plasma in analyzing trace elements is described, along with the early history of optical spectrometry and mass spectroscopy. The characteristics and analytical performance of inductively coupled plasma which is the most widely used in atomic spectrometry are explained and compared with other kinds of plasmas such as ICP, DC-arc, and MIP.

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Aplasma-interface is considered the most mysterious part of an inductively coupled plasma mass spectrometer system in terms of understanding its operational mechanism. After a brief explanation of the basic structure of the inductively coupled plasma mass spectrometer and how it works, the plasma-interface is discussed in regard to its complex operation and approaches to investigating its behavior. In particular, the position and shape of the plasma boundary seem to be important to understand the instrument's sensitivity.

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Applications of inductively coupled plasma mass spectrometry (ICP-MS) to the determination of long-lived radionuclides in environmental samples were summarized. In order to predict the long-term behavior of the radionuclides, related stable elements were also determined. Compared with radioactivity measurements, the ICP-MS method has advantages in terms of its simple analytical procedures, prompt measurement time, and capability of determining the isotope ratio such as²⁴⁰Pu/²³⁹Pu, which can not be separated by radiation. Concentration of U and Th in Japanese surface soils were determined in order to determine the background level of the natural radionuclides. The ²³⁵U/²³⁸U ratio was successfully used to detect the release of enriched U from reconversion facilities to the environment and to understand the source term. The ²⁴⁰Pu/²³⁹Pu ratios in environmental samples varied widely depending on the Pu sources. Applications of ICP-MS to the measurement of I and Tc isotopes were also described. The ratio between radiocesium and stable Cs is useful for judging the equilibrium of deposited radiocesium in a forest ecosystem.

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Arsenic originating from the lithosphere is widely distributed in the environment. Many arsenicals in the environment are in organic and methylated species. These arsenic compounds in drinking water or food products of marine origin are absorbed in human digestive tracts, metabolized in the human body, and excreted viatheurine. Because arsenic shows varying biological a spects depending on its chemical species, the biological characteristics of arsenic must be determined. It is thought that some metabolic pathways for arsenic and some arsenic circulation exist in aqueous ecosystems. In this paper, the current status of the speciation analysis of arsenic by HPLC/ICP-MS (High Performance Liquid Chromatography-Inductively Coupled Plasma Mass spectrometry) in environmental and biological samples is summarized using recent data.

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Recently, the precise isotope ratios of some refractory elements in meteorites have been reported using inductively coupled plasma mass spectrometry. The in situ decay of ¹⁸²Hf (T_1/2=9 Myr), which was produced at the latest nucleosynthesis, is recognized in many meteorites as isotopic anomalies of its daughter isotope, ¹⁸²W. The degrees of relative ¹⁸²W isotopic deviation in extra-terrestrial and terrestrial silicate samples vary from +0.3 % to ?-?0 % related to the size of their parent bodies. One ready interpretation of its correlation is the difference in timing of metal-silicate separation in the parent bodies. Between the earth and meteorite parent bodies, the difference is calculated to be about four times of the half-life of¹⁸²Hf, equivalent to 36 Myr.

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This paper describes the application of trace elemental analysis using ICP-AES and ICP-MS to criminal investigation. The comparison of trace elements, such as Rb, Sr, Zr, and so on, is effective for the forensic discrimination of glass fragments, which can be important physical evidence for connecting a suspect to a crime scene or to a victim. This procedure can be applied also to lead shotgun pellets by the removal of matrix lead as the sulfate precipitate after the dissolution of a pellet sample. The determination of a toxic element in bio-logical samples is required to prove that a victim ingested this element. Arsenous acids produced in Japan, China, Germany and Switzerland show characteristic patterns of trace elements characteristic to each country.

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The origin of high energy particles seen radiating in astrophysical synchrotron sources is still a major unresolved problem in high-energy and plasma as trophysics. The diffusive/Fermi shock acceleration under turbulent fields has been discussed as one of important processes in the production of the high-energy particles, but alternative mechanisms that can accelerate particles in a short time scale have been recently discussed as efficient non-thermal particle acceleration mechanisms. First we review the standard diffusive/Fermi acceleration, and then discuss new ideas involving the direct/fast acceleration mechanisms of the magnetic reconnection and the electron shock surfing process.

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Gamma-raybursts (GRBs) are the most explosive events after the big bang. For a few seconds a GRB be comes the brightest object in the Universe, overshining the rest of the Universe combined. Clearly this reflects extreme conditions that are fascinating and worth exploring. GRB observations were recently revolutionised by the discovery of the delayed X-ray emission, called ”afterglow”. These observations revealed that the deceleration of relativistically expanding fireballs causes GRBs. I discuss special relativistic effects that play an important role in the fireball model.

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The distribution function of the reacting particles' center of gravity isderived in order to determine the energy distribution of particles produced by fusion reaction. It is shown that the distribution function of the reacting particles' center of gravity becomes a Maxwellian distribution regardless of energy dependence of the reaction cross section when two Maxwellian distributions of fuel particles interact. The 14.7 MeV protons produced by D³He reaction have an energy spread of about 2 MeV due to the thermal motion of the center of gravity. About 90 % of the kinetic energy of the fusion protons can be converted into electricity if a one-stagedirect-current direct energy converter is used to recover the protons' kinetic energy.

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