Deformed quadrupole magnets for big-acceptance spectrometer

• Project/Area Number: 16540227
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Particle/Nuclear/Cosmic ray/Astro physics
• Research Institution: Yamagata University
• Principal Investigator: KATO Seigo Yamagata University, Faculty of Science, Professor, 理学部, 教授 (70013422)
• Co-Investigator(Kenkyū-buntansha): HASHIMOTO Osamu Tohoku University, Faculty of Science, Professor, 大学院・理学研究科, 教授 (50092292)
• Project Period (FY): 2004 – 2005
• Project Status: Completed (Fiscal Year 2005)
• Budget Amount: ¥3,500,000 (Direct Cost: ¥3,500,000); Fiscal Year 2005: ¥800,000 (Direct Cost: ¥800,000); Fiscal Year 2004: ¥2,700,000 (Direct Cost: ¥2,700,000)
• Keywords: magnetic spectrometer / quadrupole magnet / magnetic field distribution / three-dimensional distribution / 3次元磁場計算

Research Abstract

In order to design a big-acceptance magnetic spectrometer, we often have to utilize deformed quadrupole magnets. In present research, we treated quadrupole magnets whose bore are tapered along the symmetry axis. We tried to find a suitable trial function to express the magnetic field distribution with as small number of parameters as possible.
With the three-dimensional magnetic field calculating program TOSCA, we calculated the field distribution for 60 cases of the geometry and the electric current (3 cases of length, 5 cases of the bore taper, 4 cases of current). 294 data points in the region of interest for each case were compared with the trial function.
In the case of the fixed-bore (ordinary) quadrupole magnets, 7 length-independent parameters were extracted by the fit to 882 data point of 3 cases of length.
In the case of the tapered-bore (deformed) quadrupole magnets, 10 parameters were necessary to reproduce the 4410 data points of 3 lengths and 5 tapers. Because the parameters are independent not only of the lengths, but also of the tapers, we can reproduce the field distributions of arbitrary lengths and tapers. We were able to extract the current-independent parameters by fitting to 17640 data points of 3 lengths, 5 tapers and 4 currents although the standard deviation became 2 times bigger than the fixed-bore case.

Research Products

• [Journal Article] Nuclear astrophysics at the east drip line (2006)
  • Author(s): S.Kubono,..., S.Kato,....(26)
  • Journal Title: The European Physical Journal, A 10-1140 Pages: 1-6
• [Journal Article] An improved description of magnetic fringing field (2005)
  • Author(s): S.Kato
  • Journal Title: Nuclear Instruments and Methods in Physics Research A540 Pages: 1-13
  • Description: 「研究成果報告書概要(和文)」より
• [Journal Article] Study of stellar reactions in explosive hydrogen burning with CRIB (2005)
  • Author(s): S.Kubono,..., S.Kato,....(32)
  • Journal Title: Nuclear Physics, A 758 Pages: 733-736
• [Journal Article] An improved description of magnetic fringing field (2005)
  • Author(s): S.Kato
  • Journal Title: Nuclear Instruments and Methods in Physics Research A 540 Pages: 1-13
• [Journal Article] Low-energy radioisotope beam separator CRIB (2005)
  • Author(s): Yanagisawa, Y., Kubono, S., Teranishi, T., Ue, K., Michimasa, S., Notani, M., He, J.J., Ohshiro, Y., Shimoura, S., Watanabe, S., Yamazaki, N., Iwasaki, H., Kato, S., Kishida, T., Morikawa, T., Mizoi, Y.
  • Journal Title: Nuclear Instruments and Methods in Physics Research A 539 Pages: 74-83
• [Journal Article] Direct measurement of the astrophysical reaction ^<14>O(α,p)^<17>F (2004)
  • Author(s): M.Notani, S.Kubono, T.Teranishi et al.(23 other authors)
  • Journal Title: Nuclear Physics A 738 Pages: 411-415
• [Journal Article] Basic instrumentation for Hall A at Jefferson Lab (2004)
  • Author(s): Alcorn J., Anderson B.D., Aniol K.A., Annand J.R.M., Auerbach L.et al.
  • Journal Title: Nuclear Instruments and Methods in Physics Research A 522 Pages: 294-346