本センターでは次のような研究がこれまで行われています。
別刷りの請求先：S. Ban (s.ban kek.jp) または H. Hirayama (hideo.hirayama kek.jp).(kek.jpの前に@を補ってください。）

高エネルギー陽子から発生する中性子の遮蔽体中での減衰、遮蔽設計法に関する 研究

• S. Ban et al., "Measurement of Transverse Attenuation Length for Paraffin, Heavy Concrete and Iron around an External Target for 12 GeV Protons", Nucl. Instr. and Methods, 174(1989)271-276.
• S. Ban et al., "Measurement of Secondary Neutron Fluxes around Beam Stop for 500 MeV Protons", Nucl. Instr. and Methods, 184(1981)409-412.
• S. Ban and H. Hirayama,"Comparison Study of Shielding Design Method for High Energy Protons (in Japanese)", KEK Internal 80-9(1980).
• H. Hirayama et al., "Inter-comparison of the Medium-Energy Neutron Attenuation in Iron and Concrete", Presented at Thid Specialists' Meeting on Shielding Aspects of Accelerators, Targets and Irradiation Facilities, Sendai, Japan, May 12-13, 1997, KEK Preprint 97-29.
• H. Hirayaam et al., "Inter-comparison of the Medium-Energy Neutron Attenuation in Iron and Concrete(2)", Presented at SATIF4, Knoxville, Tennessee, USA, September 16-17,1998, KEK Preprint 98-164.

高エネルギー電子加速器の中性子遮蔽に関する研究

• H. Hirayama and S. Ban, "Neutron Dose Equivalent Outside the Lateral Shielding of an Electron Linear Accelerator Operating at 0.48-2.15 GeV", Health Physics, 56(1989)947-952.
• S. Ban and H. Hirayama, "The Shielding Design Methods of the Synchrotron Radiation Facility, Part I:Accelerator (in Japanese)", KEK Report 89-11(1989).

電子・陽電子蓄積リングで問題となるガス制動輻射に関する研究

• S. Ban et al.,"Measuement of Absorbed Dose in Water Irradiated by 2.5-GeV Bremsstrahlung", Health Physics, 53(1987)67-72.
• H. Hirayama et al.,"Investigation of Electromagnetic Cascades Produced in Lead by 2.5-GeV Bremsstrahlung", Nucl. Sci. Eng., 96(1987)66-72.
• S. Ban et al.,"Estimation of Absorbed Dose due to Gas Bremsstrahlung from Electron Storage Rings", Health Physics, 57(1989)407-412.

遮蔽グループでは、実験的データが最も求められている高エネルギー電子により 発生する高エネルギー中性子のスペクトル測定や高エネルギー電子により 種々の物質中に生成する放射性核種の種類と量の測定を京大や韓国のグループと 共同して、ATF (Accelerator Test Facility) とPALで実施しています。

• T. Sato et al.,"Measurements of High-Energy Photonuclear Reaction Yields in the 2.5-GeV Electron Beam Stop", Nucl. Instr. Methods A 401(1997) 476-490, KEK Preprint 97-159.
• T. Sato et al., "Modification of photo-nuclear cascade evaporation code PICA95 at energies below 150 MeV", Nucl. Instr. Meth., A 437(1999)471-480.
• H. D. Lee et al., "Photoneutron Spectra from Thin Targets Bombarded with 2.0 GeV Electrons", J. Nucl. Sci. Tech., Suppl. 1(2000)207-211.
• T. Saato, "Experimental Setup for Measurements of high Energy Photoneutron Spectra from Thick Targerts", J. Nucl. Sci. Tech., Suppl. 1(2000)202-206.

国内の研究者との共同研究

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加速器遮蔽に関する基本的な検討（中性子にビルドアップ係数、源弱距離等）を 国内の研究者と共同で行っています。

• K. Shin et al., "Point Isotropic Build-up Factors of Medium Energy Neutrons for Concrete, Iron and a Double Layer of Iron followed by Concrete", Radat. Ptot. Dosi., 71, 269-278(1997).
• H. Hirayama et al., "Inter-comparison of the Medium-Energy Neutron Attenuation in Iron and Concrete", Proc. SATIF3, Tohoku University, Sendai, Japan, 12-13 May 1997, 185-195, NEA Proceedings. (KEK Preprint 97-29).
• H. Hirayama, "Inter-comparison of the Medium-Energy Neutron Attenumatiuon in Iron and Concrete (2)", Prroc. SATIF4, Knoxville, Tennessee, USA, September 17-18, 1998, 143-154, NEA Proceedings. (KEK Preprint 98-164).
• Hirayama, H., "Inter-comparison of the Medium-Energy Neutron Attenuation in Iron and Concrete (3)", Presented at SATIF5, Paris, France, July 18-21, 2000 (KEK Preprint 2000-49).