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Seya, Michio; Kureta, Masatoshi; Soyama, Kazuhiko; Nakamura, Hironobu; Harada, Hideo; Hajima, Ryoichi
Proceedings of INMM 55th Annual Meeting (Internet), 10 Pages, 2014/07
JAEA has been implementing development programs of basic technologies of the following advanced NDA (non-destructive assay) of nuclear material (NM) for nuclear safeguards and security. (1) Alternative to 
He neutron detection using ZnS/B
O
ceramic scintillator, (2) NRD (neutron resonance densitometry) using NRTA (neutron resonance transmission analysis) and NRCA (neutron resonance capture analysis), (3) NRF (nuclear resonance fluorescence)-NDA using laser Compton scattered (LCS) 
-rays (intense mono-energetic -rays). The development program (1) is for NDA systems that use ZnS/BO ceramic scintillator as alternative neutron detector to He for coming shortage of its supply. The program (2) is for a NDA system of isotopic composition measurement (non-destructive mass spectroscopy) in targets such as particle-like melted fuel debris using NRTA and NRCA. The program (3) is for NDA systems using a specific NRF reaction of certain Pu/U isotope caused by mono-energetic LCS -ray with energy tuned to the specific excited state of the isotope. This paper introduces above three programs.
Minehara, Eisuke
Nuclear Instruments and Methods in Physics Research A, 557(1), p.16 - 22, 2006/02
Times Cited Count：11 Percentile：60.27(Instruments & Instrumentation)The JAERI FEL facility at Tokai, Ibaraki, Japan has been well known one of the two existing and operating superconducting energy recovery linacs together with one more of JLAB (Jefferson national accelerator facility) FEL facility at Newport News, Virginia, U.S.A. We have independently and successfully developed one of the most advanced and newest accelerator technologies named "superconducting energy recovery linacs (ERLs)" and the application technologies using ERLs in future. We plan to report the current high power FEL upgrade program research, stress corrosion cracking prevention technology research, large current and high brightness photoelectron gun research of negative-electron affinity (NEA) photocathode and NEA electron-excitation cathode as the most important elemental technology in realizing many powerful ERLs.
Minehara, Eisuke
Proceedings of 2nd Annual Meeting of Particle Accelerator Society of Japan and 30th Linear Accelerator Meeting in Japan, p.55 - 56, 2005/07
The next generation high brightness and high current electron source like a photo cathode, a thermionic cathode, a crystal Diamond electron cathode and others would be expected to realize the next generation ERL (energy recovery linac) based light source and SASE X-ray free-electron laser. The JAERI FEL group has recently started to develop a new crystal Diamond electron cathode technology for high current, high brightness, and long life electron source. In the presentation, we plan to explain and to discuss our strategy and a preliminary experimental measurements of the crystal Diamond cathode, and related Diamond cathode evaluation system.
Hajima, Ryoichi; Suwada, Tsuyoshi*
Hoshako, 18(3), p.200 - 201, 2005/05
no abstracts in English
Minehara, Eisuke; Hajima, Ryoichi; Sawamura, Masaru; Nagai, Ryoji; Kikuzawa, Nobuhiro; Nishimori, Nobuyuki; Iijima, Hokuto; Nishitani, Tomohiro; Kimura, Hideaki*; Oguri, Daiichiro*; et al.
Proceedings of 13th International Conference on Nuclear Engineering (ICONE-13) (CD-ROM), 10 Pages, 2005/05
The JAERI FEL has recently discovered the new FEL lasing of 255fs ultra fast pulse, 6-9% high-efficiency, one gigawatt high peak power, a few kilowatts average power, and wide tunability of medium and far infrared wavelength regions at the same time. Using the new lasing and energy-recovery linac technology, we could extend a more powerful and more efficient free-electron laser (FEL) than 10kW and 25%, respectively, for nuclear industry, pharmacy, medical, defense, shipbuilding, semiconductor industry, chemical industries, environmental sciences, space-debris, power beaming and so on. In order to realize such a tunable, highly-efficient, high average power, high peak power and ultra-short pulse FEL, we need the efficient and powerful FEL driven by the JAERI compact, stand-alone and zero boil-off super-conducting RF linac with an energy-recovery geometry. Our discussions on the FEL will cover the application of non-thermal peeling, cutting, and drilling to decommission the nuclear power plants, and to prevent stress-corrosion cracking in nuclear industry and roadmap for the industrial FELs, the JAERI compact, stand-alone and zero-boil-off cryostat concept and operational experience, the new, highly-efficient, high-power, and ultra fast pulse lasing mode, and the energy-recovery geometry.
Hajima, Ryoichi
Japanese Journal of Applied Physics, Part 2, 42(8A), p.L974 - L976, 2003/08
Times Cited Count：21 Percentile：61.65(Physics, Applied)A first-order transform matrix is proposed to calculate electron beam emittance dilution arising from coherent synchrotron radiation (CSR) in a next-generation light source based on an energy-recovery linac. The matrix approach enable us to scan a lot of parameters for the design of achromatic cells of minimum emittance dilution. The emitatce dilution can be minimized when the CSR wake dispersion matches to the betatron function envelope at the achromatic cell exit.
Minehara, Eisuke; Yamauchi, Toshihiko; Sugimoto, Masayoshi; Sawamura, Masaru; Hajima, Ryoichi; Nagai, Ryoji; Kikuzawa, Nobuhiro; Nishimori, Nobuyuki; Shizuma, Toshiyuki
Proceedings of 27th Linear Accelerator Meeting in Japan, p.21 - 23, 2002/08
The JAERI superconducting rf linac-based free-electron laser(FEL) has been modified to recover the beam energy after the lasing utilizing a 360 degree recirculating loop and other components. Recent progress on the energy recovery experiments and future plans of the JAERI superconducting rf linac-based FELs will be reported and discussed briefly.
Minehara, Eisuke; Hajima, Ryoichi; Sawamura, Masaru; Nagai, Ryoji; Nishimori, Nobuyuki; Kikuzawa, Nobuhiro; Sugimoto, Masayoshi; Yamauchi, Toshihiko; Hayakawa, Takehito; Shizuma, Toshiyuki
Proceedings of 13th Symposium on Accelerator Science and Technology, p.150 - 154, 2001/10
We need a powerful and efficient free-electron laser(FEL) for industrial uses, for examples, pharmacy, medical, defense, shipbuilding, semiconductor industry, chemical industries, environmental sciences, space-debris, power beaming and so on. In order to realize such a tunable, highly-efficient, high average power, high peak power and ultra-short pulse FEL, the JAERI FEL group and I have successfully demonstrated the efficient and powerful FEL driven by a compact, stand-alone and zero-boil-off super-conducting rf linac with an energy-recovery geometry. Our discussions on the FEL will cover market-requirements for the industrial FELs, some answers from the JAERI compact, stand-alone and zero-boil-off cryostat concept and operational experience over these 8 years, our discovery of the new, highly-efficient, high-power, and ultra-short pulse lasing mode, and the energy-recovery geometry.
Minehara, Eisuke
Hoshako, 14(3), p.182 - 189, 2001/06
We would like to explain reccent developments and future plans of the JAERI(Japan Atomic Energy Research Institute) free-electron lasers driven by a superconducting rf linac with an energy recovery loop. In the beginning of February 2000, we could exceed our 1-kW design goal and finally reach 2.34kW in quasi-continuous wave(CW) operation with a very high extraction efficiency of 5 percent or more. The high power and highly-efficient lasing has recently been found to be a novel one, a few cycle lasing of 250fs, and about 1 GW peak at the perfect synchronism without lethargy.
Hajima, Ryoichi; Seya, Michio
no journal, ,
The QST and the JAEA are proposing an ERL (energy recovery linac) -based Compton source to produce high flux photons (1013 ph/s) in MeV region with energy tenability for non-destructive assay (NDA) of all nuclides (including nuclear materials (NM)) utilizing nuclear resonant fluorescence (NRF). We can apply the proposed NDA system to nuclear security and nuclear safeguards for analyzing NM in severe conditions such as under very high radiation background or in deep inside material. For these applications we have studied NDA of isotopes in transmission geometry for measurement of NM inside a thick wall canister and in scattering geometry for measurement of NMs of spent fuel in water or detection of NM in a heavy shield. We present our efforts on these.
