Journal of the Particle Accelerator Society of Japan
Online ISSN : 2436-1488
Print ISSN : 1349-3833
Volume 10, Issue 4
Displaying 1-13 of 13 articles from this issue
Preface
Articles
  • Tsuyoshi SUWADA
    2014Volume 10Issue 4 Pages 226-237
    Published: January 31, 2014
    Released on J-STAGE: March 01, 2023
    JOURNAL FREE ACCESS

    The development of alignment techniques is particularly essential for long linacs to stabilize the acceleration and transportation of particle beams with higher charge intensities, to preserve the beam quality and to increase the injection efficiency of the beams into storage rings. Alignment measurements with a resolution of ±0.1 mm cannot be easily performed for long linacs(> 100 m)while conventional optical alignment systems with a high-precision telescope and a laser tracker, etc. are widely used for relatively short linacs(< 100 m). The laser-based alignment technique is an alternative method to accurately locate accelerating devices of the long linac on a straight line, where the laser beam can be used as a long fiducial straight line. Such laser-based alignment technique was implemented at the construction stage of the KEK injector linac in 1982; however, the high stabilization of the long laser-based fiducial line has not been realized even until now. A laser beam with higher stabilization has been implemented as a 500-m-long fiducial straight line for alignment measurements by the injector linac group in March 2013. We experimentally investigated the propagation and stability characteristics of the laser beam passing through laser pipes in vacuum. Pointing stability at the last fiducial point with the transverse displacements of ±40 μm level in one standard deviation by applying a feedback control was successfully obtained. This pointing stability corresponds to an angle of ±0.08μrad. This system is now fully exhibiting the successful results for the high-precision alignment of the injector linac currently in progress.

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Topics
  • Ryoichi HAJIMA, Masaru SAWAMURA, Yoshihisa IWASHITA
    2014Volume 10Issue 4 Pages 238-245
    Published: January 31, 2014
    Released on J-STAGE: March 01, 2023
    JOURNAL FREE ACCESS

    We have launched a development program of superconducting spoke cavities for electron beam acceleration. While the spoke cavity was originally invented for proton and ion acceleration for a velocity range of β=0.3–0.5, it can be also applicable to electron acceleration, β=1, with a minor modification. We plan to design and fabricate superconducting spoke cavities for laser Compton scattered photon sources, where the spoke cavities are expected to realize a compact industrial-use X-ray source with a reasonable cost and easy operation. In this paper, we describe features of the spoke cavity and results of cavity shape optimization for electromagnetic and mechanical properties.

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  • Kei SUGITA
    2014Volume 10Issue 4 Pages 246-249
    Published: January 31, 2014
    Released on J-STAGE: March 01, 2023
    JOURNAL FREE ACCESS

    An international accelerator complex FAIR (Facility for Antiproton and Ion Research in Europe) will be constructed at the site of GSI Helmholtzzentrum für Schwerionenforschung GmbH, Darmstadt, Germany. An overview of GSI and the status of FAIR project will be presented.

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Education
Meeting Report
Book Review
Notice Board & PASJ Announcements
Table of Contents - Volume 10
Application form for Particle Accelerator Society of Japan/List of Supporting Members
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