第10回NCT学会 June 17, 2014 岡山大学 16th ICNCT, Helsinki, Finland I. Murata, Osaka University 村田 1 Mock-up Experiment at Birmingham University for BNCT Project of Osaka University - Outline of the Experiment - I. Murata1, S. Yoshihashi1, M. Sakai1, M. Manabe1, N. Zushi1, E. Hoashi1 I. Kato2, S. Kuri3, S. Kawase4, S. Oshiro4, M. Nagasaki5, H. Horiike1 1Graduate School of Engineering, Osaka University, Osaka, Japan 2Graduate School of Dentistry, Osaka University, Osaka, Japan 3Mitsubishi Heavy Industries Mechatronics Systems, Ltd., Kobe, Japan 4Sumitomo Corporation, Tokyo, Japan 5Nagasaki Iron Works Co., Ltd., Okayama 705-0022, Japan June 17, 2014 16th International Congress on Neutron Capture Therapy Pörssitalo, Helsinki, Finland 第10回NCT学会 June 17, 2014 岡山大学 16th ICNCT, Helsinki, Finland I. Murata, Osaka University 村田 2 Table of Contents １．Outline of the BNCT Machine ２．Mockup Experiment at Birmingham University ３．To Real Machine (Abstract of Neutronics Design) ４．Conclusion 3 Target Material Selection 第10回NCT学会 June 17, 2014 岡山大学 16th ICNCT, Helsinki, Finland I. Murata, Osaka University 村田 Liquid Li Solid Li Be Energy 2.1 MeV ～ 2.8 MeV (> 10mA) 2.1 MeV ～ 2.8 MeV (> 10mA) 8 MeV(5mA) ～ 30 MeV(1mA) Target Liquid Li (7Li(p,n) reaction) Thin Li foil (7Li(p,n) reaction) Be plate (9Be(p,n) reaction) Problem ・Liquid Li technology ・Heat load on target ・7Be production ・Frequent target exchange ・Whole body dose due to large Ep ・Activation due to large En ・Frequent target exchange Advantage ・Low specific activity ・No target exchange for more than 1 year ・Low activation compared to Be target ・On beam (Kyoto Univ.) (clinical tests ongoing) Project (in Japan) Osaka Univ. (Sumitomo Corp./MHI-MS), Tokyo Institute of Technol. National Cancer Center, Nagoya Univ. Kyoto Univ., Tsukuba Univ./KEK 3 4 第10回NCT学会 June 17, 2014 岡山大学 16th ICNCT, Helsinki, Finland I. Murata, Osaka University 村田 Osaka University p-liquid Li BNCT Machine ー Schematic Design Figure ー Neutron moderator assembly Proton beam line Control room Bending magnet Li extinguisher Accelerator Neutronics Design Irradiation room Liquid Li loop Air cooler Electromagnetic pump Main parameters of the BNCT machine Quench tank Target: Proton beam energy: Tray Beam current: Epi-thermal neutron flux: Dump tank Site: Liquid LiPower 2.5 MeV 30 mA 1x109 n/sec/cm2 FEL of Osaka University 5 第10回NCT学会 June 17, 2014 岡山大学 16th ICNCT, Helsinki, Finland I. Murata, Osaka University 村田 Neutronics Design of Neutron Moderator Assembly 1. Design goal ・IAEA’s criteria ✓ φepi ＞ 1x109 n/sec/cm2 at 30mA ✓ Epi to thermal ratio ＞ 20 ✓ Fast and gamma-ray contribution ＜ 2x10-13 Gy・cm2 ✓ Current flux ratio ＞ 0.7 ・Whole body dose < 0.25 Sv/irradiation (press-released value) ・Tritium production < 100 Bq/g-Li/3-years ・Activation < Clearance level (except for some material near the target) 2. Design codes ・Transport code: MCNP5.1.40 Model 3-d by GEOMIT(CAD/MCNP conversion) Tally F2(Flux), F4(Activation), F6(Dose) Nuclear data JENDL-4 Source term Intensity and angular distribution(Exp. at Tohoku-u) Energy distribution (DRSORG2000) ・Activation： EASY（FISPACT） ・Dose estimation： SERA /JCDS (to be determined before clinical tests) ↓ We should validate our code system before design of our new BNCT machine. → Mockup experiments carried out at Birmingham University last year. 第10回NCT学会 June 17, 2014 岡山大学 16th ICNCT, Helsinki, Finland I. Murata, Osaka University 村田 6 Table of Contents １．Outline of the BNCT Machine ２．Mockup Experiment at Birmingham University ３．To Real Machine (Abstract of Neutronics Design) ４．Conclusion 7 Experimental Approaches to the Real BNCT Machine Source term measurement 第10回NCT学会 June 17, 2014 岡山大学 16th ICNCT, Helsinki, Finland I. Murata, Osaka University 村田 Mockup exp. of neutron moderator assembly Real BNCT machine At Birmingham Univ. Tohoku Univ. (2012) (2013 May～July) 1mA ・Neutron source term measurement for design of real BNCT machine 1mA Beam current 30mA ・Demonstrate epi-thermal neutron ・Accelerator selection production by p-Li neutrons ・Lithium loop development ・Neutron and γ-ray dose measurement ・Verification of design code system and ・Construction of neutron moderator assembly confirmation of its accuracy 8 第10回NCT学会 June 17, 2014 岡山大学 16th ICNCT, Helsinki, Finland I. Murata, Osaka University 村田 Mockup Experiments at Birmingham University Date: Place: May 22nd ～ July 1st, 2013 Birmingham University, UK Dynamitron accelerator (in Prof. S. Green’s labo.) Particle： Energy： Beam current： Proton 2.25MeV、2.65MeV、2.95MeV 450 mA in average Target 1 mm thick Lithium sheet cooled with heavy water Neutron intensity Energy： 700keV at maximum (7Li(p,n)7Be） Intensity： ～ 4.5×1011 n/sec in average Measurement Neutron flux Gamma-ray dose Gold foil Glass detector (hand made) Ionization chamber (PTW) 9 第10回NCT学会 June 17, 2014 岡山大学 16th ICNCT, Helsinki, Finland I. Murata, Osaka University 村田 Dynamitron Accelerator in Birmingham University Dynamitron Outside cover Construction: Accelerator voltage: Beam current: Control room Very old (～1970) ~ 3 MV ~ 1 mA Design of Neutron Moderator Assembly Boric acid solution for Birmingham Experiment 第10回NCT学会 June 17, 2014 岡山大学 16th ICNCT, Helsinki, Finland I. Murata, Osaka University 村田 10 Proton beam Graphite Boric acid solution Lead Li target Fluoride Deuteride Radial direction Vertical direction Human body phantom Design feature ○To keep an intense epi-thermal neutron flux, though the source is not so strong, → Mixture material of fluoride and deuteride was employed as collimator. Neutron Moderator Assembly in Birmingham Experiment 11 Human body phantom Head Body 第10回NCT学会 June 17, 2014 岡山大学 16th ICNCT, Helsinki, Finland I. Murata, Osaka University 村田 Proton Beam Upper tanks of boric acid solution Leg Side tanks of boric acid solution Irradiation area Treatment Room Medical Physics (R11) University of Birmingham, UK Lithium target at the center of the assembly 12 Radiation Measurement 第10回NCT学会 June 17, 2014 岡山大学 16th ICNCT, Helsinki, Finland I. Murata, Osaka University 村田 〇Foil activation with gold foils Gold foil Glass To measure ・Thermal neutron flux ・Cadmium ratio ＝(RR of 197Au) / (RR of 197Au with Cd cover) Position: Inside and outside the collimator and phantom 〇Glass detectors To measure ・Gamma-ray dose (Gy) Position: Inside and outside the collimator and phantom Remark: Originally aim at measuring neutron dose at the same time using lithium Glass with Li 〇Ionization chamber To measure ・Gamma-ray dose (Gy) Position: Outside the collimator and phantom 30cc IC (PTW) Neutron Flux Measurement with Gold Foil 13 - without Phantom Neutron Flux [neutrons/cm2/sec] 20 Number of data 第10回NCT学会 June 17, 2014 岡山大学 16th ICNCT, Helsinki, Finland I. Murata, Osaka University 村田 15 10 5 6.E+06 4.E+06 2.E+06 Collimator radius(100 mm) 1.E+04 0 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 C/E 2.0 0 200 400 600 800 Distance from the center [mm] Radial distribution of calculated epi-thermal neutron flux Excellent agreement was obtained between experimental and calculated reaction rates of gold foils. → Design error can be suppressed to be less than 20 %. → C/E just under the assembly is less than 1.01. From the analysis, it was confirmed that the epi-thermal neutron flux was well collimated. → It can thus suppress the whole body dose. C/E of reaction rate of gold foil ✔ The details will be presented by S. Tamaki in PS2 P 01 on Wed. 第10回NCT学会 June 17, 2014 岡山大学 16th ICNCT, Helsinki, Finland I. Murata, Osaka University 村田 Gamma-ray dose measurement with glass dosimeter 14 45 40 35 30 25 20 15 10 5 0 Gamma-ray dose [mGy] Gamma-ray dose [mGy] - without Phantom Experiment Calculation 0 200 400 600 800 1000 45 40 35 30 25 20 15 10 5 0 Experiment Calculation 0 200 400 600 800 1000 Distance from the center [mm] Distance from the center [mm] Radial distribution of gamma-ray dose Vertical distribution of gamma-ray dose Gamma-ray dose decreases with increase of the distance from the cente. At around the center, measured values are twice of calculation → Neutron contribution to glass detector ↓ ○Development of lead filter method to remove neutron dose contribution. ✔ The details will be presented by S. Yoshihashi in PS2 P 03 on Wed. 第10回NCT学会 June 17, 2014 岡山大学 16th ICNCT, Helsinki, Finland I. Murata, Osaka University 村田 15 Table of Contents １．Outline of the BNCT Machine ２．Mockup Experiment at Birmingham University ３．To Real Machine (Abstract of Neutronics Design) ４．Conclusion 16 Upper floor 第10回NCT学会 June 17, 2014 岡山大学 16th ICNCT, Helsinki, Finland I. Murata, Osaka University 村田 Design of Real Machine ー Neutron Moderator Assembly ー Concrete Carbon sheet Target room PE(Boron) p-beam Carbon Liquid Li target Iron PE(Boron) Lead Cadmium Aluminum frame Bismuth Irradiation room Design features: Epi-thermal ○Neutron beam direction neutrons ＝ proton beam direction → Assembly can be built in the wall. Fluolide Concrete Deuteride Thickness and radius (together with Ep) are changed for tumor to adjust beam radius and neutron spectrum. 第10回NCT学会 June 17, 2014 岡山大学 16th ICNCT, Helsinki, Finland I. Murata, Osaka University 村田 17 Extrapolated Real Machine Performance Evaluation condition Tumor BPA T/N ratio Mucosa dose Irradiation time ： ： ： ： ： Head and neck cancer 24 ppm (ave.) Values supplied by 3.5 (ave.) Prof. Itsuro Kato 12 Gy-eq of Osaka University 30 min Extrapolated real machine performance ○Basic Themal neutron ： Epi-thermal n. ： Fast neutron ： γ-ray air dose ： ○Dose Tumor ： Normal brain ： ○Contribution Fast ： Gamma-ray ： ○Whole body Neutron ： Gamma-ray ： B+N ： Total ： 5.8x106 8.1x108 1.2x108 0.24 20 4.1 5.1 x 10-13 2.7 x 10-13 0.03 0.15 0.08 0.26 n/sec/cm2/30mA n/sec/cm2/30mA n/sec/cm2/30mA Gh/hr Gy-eq Gy-eq Gy・cm2 Gy・cm2 Sv/irradiation Sv/irradiation Sv/irradiation Sv/irradiation 18 Conclusion 第10回NCT学会 June 17, 2014 岡山大学 16th ICNCT, Helsinki, Finland I. Murata, Osaka University 村田 ・The project has started under Site for the first machine collaboration with Sumitomo Corporation and Mitsubishi Heavy Industries Mechatronics Systems, Ltd. ・Osaka University group is now carrying out design of lithium loop and neutron moderator assembly. ・Design code system and its accuracy was confirmed by mockup Institute of Free Electron Laser, experiment at Birmingham University. Osaka University What’s next? ～2013 2014～ 2014～16 2016～ Mockup experiment done to check the design code Governmental funding starts. Construction of accelerator and performance test. Clinical tests will start. 19 第10回NCT学会 June 17, 2014 岡山大学 16th ICNCT, Helsinki, Finland I. Murata, Osaka University 村田 Thank you! Special thanks to Prof. S. Green’s group, Birmingham Univ., UK for their warm support in mockup experiment.
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