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Presents information on a study which examined the negative surface ionization of hydrogen atoms and molecules. Experimental setup; Cesiation of the converter; Results.

Provides information on a study that investigated the microwave absorbing characteristics and resonance of Y-type hexagonal ferrite-rubber composites. Methodology of the study; Results and discussion on the study; Conclusion.

For certain orientations of Josephson junctions between two px-wave or two d-wave superconductors, the subgap Andreev bound states produce a 4π-periodic relation between the Josephson current I and the phase difference φ: I∝sin(φ/2). Consequently, the ac Josephson current has the fractional frequency eV/h, where V is the dc voltage. In the tunneling limit, the Josephson current is proportional to the first power (and not the square) of the electron tunneling amplitude. Thus, the Josephson current between unconventional superconductors is carried by single electrons, rather than by Cooper pairs. The fractional ac Josephson effect can be observed experimentally by measuring the frequency spectrum of microwave radiation from the junction. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

We present the design and performance of a beamline which is the source of 5–50-eV protons for surface scattering experiments. The beamline also incorporates a collector for measuring total secondary ion and electron yields. The beam forming optics are built around a commercially available gas discharge ion gun and produce a mass-selected, energy-filtered beam. Results of computer ray tracing are included to illustrate the operation of the beam optics. Tests have produced 50-pA proton beams 3.5-mm wide at 5 eV with an energy spread of about 1 eV. [ABSTRACT FROM AUTHOR]

A 100 MeV, 20 mA proton linear accelerator is being developed by the Proton Engineering Frontier Project at the Korea Atomic Energy Research Institute. 20 MeV acceleration system using radio frequency quadrupole and drift tube linac was already developed and has been tested. To operate this acceleration system with a long time, more reliable proton source is needed. A compact microwave proton source was proposed and has been designed and constructed as a prototype ion source for the 100 MeV proton linear accelerator. The design of microwave power injection system is based on the microwave proton injector at LANL and CEA. The wave power from a 2.45 GHz, 2 kW magnetron source is introduced into a compact plasma chamber with 7 cm diameter and 5 cm length through a standard tapered, double-ridged waveguide (WRD250) and a quartz window. The microwave power supply is installed on high voltage platform. Axial magnetic fields up to 1 kG can be provided with a water-cooled solenoid coil. A single-hole three electrode extraction system is designed for an extraction current up to 30 mA at a 50 kV extraction voltage. The design and initial operations of the proton source are presented. [ABSTRACT FROM AUTHOR]