H. Usami

Sumitomo Heavy Industries, Ltd, Edo, Tōkyō, Japan

Are you H. Usami?

Claim your profile

Publications (5)7.58 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: The 10-T wiggler is an iron-cored superconducting wiggler destined for Electrotechnical Laboratory’s 800-MeV electron storage ring to enhance the available radiation. The design and manufacturing contract for this magnet was started in April 1990 and was preceded by a feasibility study. The major features of the magnet are described in the article. Also, the effect of the superconducting wiggler with high magnetic field on the stored electron beam has been simulated.
    Review of Scientific Instruments 02/1995; 66(2):1960-1963. DOI:10.1063/1.1145770 · 1.61 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The design of a 10‐T superconducting wiggler as a synchrotron radiation source for angiography has been carried out to be installed in an 800‐MeV electron storage ring, TERAS, at Electrotechnical Laboratory (ETL). Synchrotron radiation generated by the wiggler has a critical photon energy of 4.47 keV and the radiation spectrum identical to that from a 2.5‐GeV storage ring with a bending radius of 8.3 m. The magnet of the wiggler consists of three pairs of iron‐cored superconducting coils designed to provide a peak field of 10.5 T on the beam trajectory. The effect of the wiggler on the storage ring has been investigated and a pair of quadrupole doublets on both sides of the wiggler can compensate a large deviation of the betatron tune.
    Review of Scientific Instruments 02/1992; DOI:10.1063/1.1142742 · 1.61 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: With successful conditioning, the beam lifetime of the SORTEC SR ring extended over 50 h at our nominal beam current of 200 mA. The conditioning and the results are discussed from the point of (i) optimization of operating point, (ii) high vacuum, and (iii) effective removal of the produced ion.
    Review of Scientific Instruments 02/1992; DOI:10.1063/1.1142650 · 1.61 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The construction and the initial beam conditioning of a 1-GeV synchrotron radiation (SR) source facility at SORTEC Corporation were successfully completed in 1989. The regular operation for lithography experiments was started in April 1990, and highly stable operation has been maintained for over one year. At present, the beam lifetime with the stored beam of 200 mA has reached over 50 hours. Due to stable beam refilling into the storage ring, automatic operation for a constant level control of the stored beam current was also successfully confirmed. In this paper, performance of the SR source will be further discussed from the viewpoint of the industrial use of the SR source for X-ray lithography in terms of stable and flexible operation, operation efficiency, utilities and radiation safety.
    Japanese Journal of Applied Physics 11/1991; 30(11B):3043-3047. DOI:10.1143/JJAP.30.3043 · 1.13 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The bunch length was measured by using a highly sensitive streak camera with a time resolution of 2 ps. It was found that fine structures appeared in the electron bunch shape and that the shapes of electron bunches were described by a Gaussian distribution on the average. The dependence of bunch length on beam current was measured for an electron beam of 607 MeV. The bunch length was well represented by a power function of beam current with an exponent of 0.197 at currents lower than 35 mA or 0.30 at high currents. The experimental results suggest that the longitudinal coupled‐bunch beam instability takes place at low beam currents and the turbulent instability dominates at high currents. It was also found from the three‐dimensional bunch shape measurements that the bunch shape tended to blow up at high currents.
    Review of Scientific Instruments 08/1989; 60(7-60):1748 - 1751. DOI:10.1063/1.1140945 · 1.61 Impact Factor