Researcher Database

KANEKO Junichi H
Faculty of Engineering Applied Quantum Science and Engineering Quantum Engineering for Materials
Associate Professor

Researcher Profile and Settings

Affiliation

  • Faculty of Engineering Applied Quantum Science and Engineering Quantum Engineering for Materials

Job Title

  • Associate Professor

Degree

  • Doctor of Engineering(The University of Tokyo)
  • Master of Business Administration(Otaru University of Commerce)

J-Global ID

Research Interests

  • ダイヤモンド・cBN等の評価と開発   放射線医用・医療工学   放射線計測   Development of radiation detectors   

Research Areas

  • Manufacturing technology (mechanical, electrical/electronic, chemical engineering) / Electronic devices and equipment
  • Life sciences / Medical systems
  • Energy / Nuclear engineering

Association Memberships

  • 医療物理学会   日本中性子科学会   応用物理学会   ニューダイヤモンドフォーラム   日本原子力学会   

Research Activities

Books etc

  • ダイヤモンドエレクトロニクスの最前線
    シーエムシー出版 2008
  • Frontier of Diamond for Electronics Applications
    CMC books 2008

MISC

  • Junichi H. Kaneko, Fumiyuki Fujita, Yuta Konno, Takuto Gotoh, Norihiko Nishi, Hideyuki Watanabe, Akiyoshi Chayahara, Hitoshi Umezawa, Nobuteru Tsubouchi, Shinichi Shikata, Mitsutaka Isobe  DIAMOND AND RELATED MATERIALS  26-  45  -49  2012/07  [Not refereed][Not invited]
     
    As part of the development of diamond radiation detectors for energy spectrometry, quality improvement of CVD diamond single crystals was conducted mainly by measures of single diamond substrates. To suppress stress resulting from unconformity of lattice spacing between a substrate and a grown layer, which sometimes causes breakage, HP/HT type IIa diamond single-crystal substrates were adopted, and it resulted successfully. In addition an off-axis (001) surface was fabricated on the substrate to reduce abnormal growth. A lift-off method was adopted to reuse the HP/HT type IIa substrate with an off-axis (001) surface. Judging from peaks caused by free exciton recombination in cathode luminescence spectra, growth conditions more strongly affected the diamond crystal quality than substrates of any kind. Energy resolution of 0.6% for alpha particles was obtained by one CVD diamond single crystal. Charge collection efficiency of approximately 100% and 95% for holes and electrons was achieved. Step bunching caused by residual gas was observed on the grown CVD diamond surface. From the perspective of charge carriers' transportation measurement, the reduction of residual gas and optimization of growth conditions are indispensable. (c) 2012 Elsevier B.V. All rights reserved.
  • Hiroki Shirato, Rikiya Onimaru, Masayori Ishikawa, Jun-ichi Kaneko, Tsuguhide Takeshima, Kenta Mochizuki, Shinichi Shimizu, Kikuo Umegaki  CANCER SCIENCE  103-  (1)  1  -6  2012/01  [Not refereed][Not invited]
     
    Respiratory motion considerably influences dose distribution, and thus clinical outcomes in radiotherapy for lung cancer. Breath holding, breath coaching, respiratory gating with external surrogates, and mathematical predicting models all have inevitable uncertainty due to the unpredictable variations of internal tumor motion. The amplitude of the same tumor can vary with standard deviations >5 mm occurring in 23% of T12N0M0 non-small cell lung cancers. Residual motion varied 16 mm (95th percentile) for the 40% duty cycle of respiratory gating with external surrogates. The 4-D computed tomography is vulnerable to problems relating to the external surrogates. Real-time 4-D radiotherapy (4DRT), where the temporal changes in anatomy during the delivery of radiotherapy are explicitly considered in real time, is emerging as a new method to reduce these known sources of uncertainty. Fluoroscopic, real-time tumor-tracking technology using internal fiducial markers near the tumor has +/- 2 mm accuracy, and has achieved promising clinical results when used with X-ray therapy. Instantaneous irradiation based on real-time verification of internal fiducial markers is considered the minimal requisite for real-time 4DRT of lung cancers at present. Real-time tracking radiotherapy using gamma rays from positron emitters in tumors is in the preclinical research stage, but has been successful in experiments in small animals. Real-time tumor tracking via spot-scanning proton beam therapy has the capability to cure large lung cancers in motion, and is expected to be the next-generation real-time 4DRT. (Cancer Sci 2012; 103: 16)
  • Improvement of crystal quality of a homoepitaxially grown diamond layer by a plasma etching treatment for a diamond substrate
    PROGRESS IN NUCLEAR SCIENCE AND TECHNOLOGY  1-  255  -258  2011  [Not refereed][Not invited]
  • Luminescence properties and Crystal structures of Pr-doped gadolinium pyrosilicate
    PROGRESS IN NUCLEAR SCIENCE AND TECHNOLOGY  288  -291  2011  [Not refereed][Not invited]
  • Improvmement of scintillation characteristics of FZ growth Ce:GPS crystals by annealing in air
    PROGRESS IN NUCLEAR SCIENCE AND TECHNOLOGY  1-  279  -281  2011  [Not refereed][Not invited]
  • M. Isobe, H. Yamanishi, M. Osakabe, H. Miyake, H. Tomita, K. Watanabe, H. Iwai, Y. Nomura, N. Nishio, K. Ishii, J. H. Kaneko, J. Kawarabayashi, E. Takada, A. Uritani, M. Sasao, T. Iguchi, Y. Takeiri, H. Yamada  REVIEW OF SCIENTIFIC INSTRUMENTS  81-  (10)  10D310-1-10D310-5  2010/10  [Not refereed][Not invited]
     
    Deuterium experiment on the Large Helical Device (LHD) is now being planned at the National Institute for Fusion Science. The fusion product diagnostics systems currently considered for installation on LHD are described in this paper. The systems will include a time-resolved neutron yield monitor based on neutron gas counters, a time-integrated neutron yield monitor based on activation techniques, a multicollimator scintillation detector array for diagnosing spatial distribution of neutron emission rate, 2.5 MeV neutron spectrometer, 14 MeV neutron counter, and prompt gamma-ray diagnostics. (C) 2010 American Institute of Physics. [doi:10.1063/1.3492383]
  • F. Fujita, A. Kakimoto, J. H. Kaneko, N. Tsubouchi, Y. Mokuno, A. Chayahara, K. Sato, Y. Konno, A. Homma, S. Shikata, M. Furusaka  DIAMOND AND RELATED MATERIALS  19-  (2-3)  162  -165  2010/02  [Not refereed][Not invited]
     
    Using lift-off method, we synthesized large self-standing plasma CVD diamond films on various substrates. Charge carrier transportation in diamond was measured using alpha particle measurements and TOF methods with a short-pulsed UV laser. The high-quality films were synthesized rapidly. We observed the maximum transit time of holes and electrons shorter than 5 ns. The lift-off method is useful to fabricate the high-quality diamond with excellent drift velocities of the charge carrier. The charge transport characteristics of our diamond films are comparable to those of a commercially available (Element Six Ltd.) electronics grade Ila diamond single crystal. (C) 2009 Elsevier B.V. All rights reserved.
  • Sohan Kawamura, Mikio Higuchi, Junichi H. Kaneko, Shusuke Nishiyama, Jun Haruna, Shohei Saeki, Shunsuke Ueda, Kazuhisa Kurashige, Hiroyuki Ishibashi, Michihiro Furusaka  CRYSTAL GROWTH & DESIGN  9-  (3)  1470  -1473  2009/03  [Not refereed][Not invited]
     
    The melting and solidification behavior of the (Gd0.9Ce0.1)(2)Si2O7 (Ce:GPS) which shows attractive scintillation performance was investigated by means of the slow cooling floating zone (SCFZ) method. Although Ce:GPS melts incongruently, the peritectic composition is estimated to be very close to the GPS composition, less than 67.0 mol % of SiO2 in the (Gd,Ce)(2)O-3-SiO2 system. Constitutional supercooling occurred when approximately 70% volume of the melt was solidified, consequently, the lamellar structure consists of Ce:GPS and the amorphous phase was obtained. On the basis of our study, it is estimated that a volume of 70% of the starting material, whose composition is SiO2 = 67 mol % in the (Gd,Ce)(2)O-3-SiO2 system at Ce 10 mol %, can be solidified as the GPS phase using top-seeded solution growth (TSSG) with the self-flux of SiO2.
  • S. Fukumoto, A. Homma, J. H. Kaneko, Y. Nishibayashi, Y. Yamamoto, A. Ueda, F. Fujita, S. Kawamura, K. Sato, T. Imai, M. Furusaka  DIAMOND AND RELATED MATERIALS  18-  (2-3)  287  -291  2009/02  [Not refereed][Not invited]
     
    Electron emission characteristics of needle-type semiconductor diamond electron emitters with pulsed bias operation were evaluated. An X-ray generation experiment was performed. Fowler-Nordheim plotting confirmed that field emission completely governed the electron emission. Maximum emission current of 4.2 mA was achieved using an n-type diamond needle. The needle tip, with area smaller than 1 mu m(2), had estimated electron emission density greater than 4.2 x 10(5) A/cm(2). The effective emission area obtained from the Fowler-Nordheim plot was several 10(-13) cm(2). For adopting and emission area of 1 X 10(-12) cm(2), the estimated electron emission density was higher than 4.2 x 10(9) A/cm(2). Furthermore, the average emission current was 0.5-0.6 mA. This large electron emission was continued for several seconds and repeatable. A threshold electric field existed for electron emission higher than 50 kV/mm; pulsed electron emissions of less than 30 ms were created by slow triangular waveform shaped bias voltage supplied at frequencies of 5-10 Hz. An improved vacuum level and pulsed bias operation prevented damage to diamond electron emitters and steady electron emission better than with thermoelectronic emission and high bias voltage supply in DC mode; continuous X-ray generation of 1 h was achieved. (C) 2008 Elsevier B.V. All rights reserved.
  • Scintillation characteristics of (Gd1-xCex)2Si2O7(x=0.025-0.25) single crystals fabricated by floating zone method
    IEEE Trans. NS  56-  (1)  328  -330  2009  [Not refereed][Not invited]
  • Measurement of charge carriers' transportation in large size self-standing CVD single crystal diamonds fabricated by a lift-off method
    Diamond and Related materials  In Press  2009  [Not refereed][Not invited]
  • Junichi H. Kaneko, Tokuyuki Teraji, Takahiro Imai, Yuuki Hirai, Satoshi Yoshizaki, Kei Satou, Souhan Kawamura, Yusuke Oshiki, Fumiyuki Fujita, Akira Homma, Toshimichi Ito, Michihiro Furusaka  JOURNAL OF NUCLEAR SCIENCE AND TECHNOLOGY  Supplement 5-  391  -394  2008/06  [Not refereed][Not invited]
     
    Radiation detectors were fabricated with layered structure diamonds comprising several micrometers of a boron-doped single crystal diamond and 20 mu m of insulating single crystal diamond layers grown on a HP/HT-type Ib diamond single crystal Substrate. To improve the yield rate of CVD diamond radiation detectors this approach was adopted. The detectors had rectification characteristics because of their boron-doped diamond contact and aluminum Schottky contact. The leakage current of one detector was less than 0.2 pA at reversed bias voltage of +50 V Energy resolutions of 2.6% and 2.8% for alpha particles from Am-241 were achieved using these detectors. The rise time of a leading edge of an Output signal from one detector was less than 20 ns, which was the fastest rise time of the measurement system; drift velocities of charge carriers were estimated to be faster than 1 x 10(5) cm/s. In addition, cathode luminescence spectra of insulating diamond layers were measured; peaks caused by free exciton recombination and 'band A' were observed. Improved crystallinity of the boron-doped diamond layer helps realization of a layered-type diamond radiation detector with higher energy resolution.
  • Y. Oshiki, J. H. Kaneko, F. Fujita, A. Homma, H. Watanabe, K. Meguro, Y. Yamamoto, T. Imai, K. Sato, K. Tsuji, S. Kawamura, M. Furusaka  DIAMOND AND RELATED MATERIALS  17-  (4-5)  833  -837  2008/04  [Not refereed][Not invited]
     
    Charge carrier dynamics in CVD homoepitaxial diamond thin films were evaluated. Thicknesses of these thin diamond films were 4.5-14 mu m. Measurement was carried out using a fast TOF system with time resolution of 150 ps. This system adopted the localized irradiation mechanism of a 213-nm UV pulsed laser. Induced current caused by charge carrier motion was simulated by a one-dimensional approximation. Then measured signals were analyzed using the physical model of induced current that was confirmed through the simulation. The best lifetimes, T, of electrons and holes in evaluated diamond films were 1.8 +/- 0.3 ns for both charge carriers. However, drift velocities and mean free paths of trapping were not determined because insufficient charge carriers arrived at the further side electrode without trapping. (C) 2008 Elsevier B.V. All fights reserved.
  • S. Fukumoto, A. Honma, J. H. Kaneko, Y. Nishibayashi, A. Ueda, Y. Yamamoto, T. Imai, F. Fujita, S. Kawamura, M. Furusaka  DIAMOND AND RELATED MATERIALS  17-  (4-5)  764  -767  2008/04  [Not refereed][Not invited]
     
    Emission currents and other characteristics of needle type diamond electron emitters were evaluated for application to diamond X-ray sources. The evaluation system consisted of a Pyrex glass vacuum chamber, a turbo molecular pump, and a - 50 kV high-voltage supplier. A needle type phosphorus-doped semiconductor diamond electron emitter was kept at 600 degrees C by ohmic heating in a vacuum environment; emission current of ca. 1.1 mu A was observed with bias voltage of - 50 W In addition, the electron orbit and intensity were estimated using an electron optics and electron gun design program 'EGUN'. Great differences were apparent between experimental and calculated results: 64 mu A electron emission current. This result was probably the result of a change in the shape of the tip of the diamond electron emitter. X-rays were generated using electrons from the diamond electron emitter with a tungsten target; energy spectra of the generated X-rays were measured. Then fluoroscopy was carried out. (C) 2008 Elsevier B.V. All rights reserved.
  • H. Ohshita, H. Iwasaki, J. Kaneko, H. Kiyamura, M. Nakao, A. Ochi, K. Ochiai, T. Takeshita, S. Tanaka  NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT  587-  (2-3)  259  -265  2008/03  [Not refereed][Not invited]
     
    Thin Gap Chambers (TGCs) will be used as a muon trigger device in the end-cap regions of the ATLAS detector. The detector will be placed in an experimental cavern approximately 100 m below the ground surface. A large amount of neutron background is expected in the cavern. Recoiled nuclei, mostly protons, emerging from the neutron interaction provide a much larger energy deposit in the gas volume than that of the minimum ionizing particle (MIP). This might cause aging and improper operation of the TGC. In order to investigate such influences, we performed a test on the operation stability of a real-use TGC under a much higher neutron flux environment than that expected in the ATLAS cavern. This paper describes the experimental results of the irradiation test using 14-MeV neutrons. The maximum flux was 3.2 x 10(5) HZ/cm(2), Which was effectively approximately nine times higher than that at the worst TGC location. It was proved that the TGC was immune to such a flux and instantaneous large signals originating from the neutrons. The mean output charge from the recoil proton at the nominal operation voltage was found to be approximately 30 times larger than that of MIP. The total fluence was 1.4 x 10(10) neutrons/cm(2), up to which the TGC operated stably and no detector deterioration was observed. This corresponds to approximately nine months of ATLAS operation at the nominal luminosity of 10(34) cm(2)/S. (C) 2008 Elsevier B.V. All rights reserved.
  • Sohan Kawamura, Junichi H. Kaneko, Mikio Higuchi, Fumiyuki Fujita, Akira Homma, Jun Haruna, Shohei Saeki, Kazuhisa Kurashige, Hiroyuki Ishibashi, Michihiro Furusaka  NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT  583-  (2-3)  356  -359  2007/12  [Not refereed][Not invited]
     
    As a novel scintillation material, the use of Ce-doped Gd(2)Si(2)O(7) was investigated. In fact, (Gd(0.9)Ce(0.1))(2)Si(6)O(7) powder showed about 1.2 times greater light output than Gd(2)SiO(5) (GSO) single crystals for alpha particles of (241)Am. Furthermore, a fast decay constant of 52 ns was obtained for alpha-particles of (241)Am. Relations between the Ce concentration, crystal structure, and luminescence characteristics were also elucidated. Results of these studies show that heavy Ce doping alters the Gd(2)Si(2)O(7) crystal structure and that the luminescence intensity is dependent not on Cc concentration, but on the triclinic structure formed by heavy Cc doping. (c) 2007 Elsevier B.V. All rights reserved.
  • Sohan Kawamura, Junichi H. Kaneko, Mikio Higuchi, Fumiyuki Fujita, Akira Homma, Jun Haruna, Shohei Saeki, Kazuhisa Kurashige, Hiroyuki Ishibashi, Michihiro Furusaka  NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT  583-  (2-3)  356  -359  2007/12  [Not refereed][Not invited]
     
    As a novel scintillation material, the use of Ce-doped Gd(2)Si(2)O(7) was investigated. In fact, (Gd(0.9)Ce(0.1))(2)Si(6)O(7) powder showed about 1.2 times greater light output than Gd(2)SiO(5) (GSO) single crystals for alpha particles of (241)Am. Furthermore, a fast decay constant of 52 ns was obtained for alpha-particles of (241)Am. Relations between the Ce concentration, crystal structure, and luminescence characteristics were also elucidated. Results of these studies show that heavy Ce doping alters the Gd(2)Si(2)O(7) crystal structure and that the luminescence intensity is dependent not on Cc concentration, but on the triclinic structure formed by heavy Cc doping. (c) 2007 Elsevier B.V. All rights reserved.
  • S. Kawamura, J. H. Kaneko, M. Higuchi, T. Yamaguchi, J. Haruna, Y. Yagi, K. Susa, F. Fujita, A. Homma, S. Nishiyama, K. Kurashige, H. Ishibashi, M. Furusaka  IEEE TRANSACTIONS ON NUCLEAR SCIENCE  54-  (4)  1383  -1386  2007/08  [Not refereed][Not invited]
     
    Growth of cerium-doped gadolinium pyrosilicate (Ce:Gd2Si2O7) single crystals, which show 2.5 times greater light output for gamma-rays and five times greater light output for alpha-particles than GSO single crystals, is accomplished using the floating zone growth method (FZ method). Although growth of Gd2Si2O7 (GPS) single crystal is considered to be difficult because it melts incongruently according to the phase diagram of Gd2O3-SiO2 system, we attempted crystal growth of Ce:GPS because of the possibility that heavy Ce doping would change the phase diagram. Transparent single crystals were obtained, although some cracks were observed in the crystals. The crystal structure was triclinic with P/1 space group and density of 5.5 g/cm(3). Two peaks, which were observed using photoluminescence spectrometry at 372 nm and 394 nm, were attributed to 5d-4f transition in Ce3+ ion. Decay times of Ce:GPS scintillation were 46 ns for gamma-ray excitation and 39 ns for alpha-particle excitation. We consider that fabrication of crack free crystals will improve the energy resolution.
  • S. Kawamura, J. H. Kaneko, M. Higuchi, T. Yamaguchi, J. Haruna, Y. Yagi, K. Susa, F. Fujita, A. Homma, S. Nishiyama, K. Kurashige, H. Ishibashi, M. Furusaka  IEEE TRANSACTIONS ON NUCLEAR SCIENCE  54-  (4)  1383  -1386  2007/08  [Not refereed][Not invited]
     
    Growth of cerium-doped gadolinium pyrosilicate (Ce:Gd2Si2O7) single crystals, which show 2.5 times greater light output for gamma-rays and five times greater light output for alpha-particles than GSO single crystals, is accomplished using the floating zone growth method (FZ method). Although growth of Gd2Si2O7 (GPS) single crystal is considered to be difficult because it melts incongruently according to the phase diagram of Gd2O3-SiO2 system, we attempted crystal growth of Ce:GPS because of the possibility that heavy Ce doping would change the phase diagram. Transparent single crystals were obtained, although some cracks were observed in the crystals. The crystal structure was triclinic with P/1 space group and density of 5.5 g/cm(3). Two peaks, which were observed using photoluminescence spectrometry at 372 nm and 394 nm, were attributed to 5d-4f transition in Ce3+ ion. Decay times of Ce:GPS scintillation were 46 ns for gamma-ray excitation and 39 ns for alpha-particle excitation. We consider that fabrication of crack free crystals will improve the energy resolution.
  • J. H. Kaneko, T. Taniguchi, S. Kawamura, K. Satou, F. Fujita, A. Homma, M. Furusaka  NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT  576-  (2-3)  417  -421  2007/06  [Not refereed][Not invited]
     
    Radiation detectors were fabricated using single and polycrystalline cubic boron nitride (cBN) crystals synthesized using a high-pressure and high-temperature (HP/HT) method. Although cBN single crystals obtained using a barium BN solvent system were nearly colorless and displayed high electrical resistance, in contrast to conventional amber-colored crystals, the single crystals exhibit a leakage current that renders them unsuitable for use in a detector. In contrast, a detector made of a cBN polycrystal synthesized by direct transformation had a very low leakage current of 0.2pA with bias voltage of 100V; it functioned as a radiation detector. From an experiment using alpha-particles, holes traversed a longer distance than electrons. It had a fast rise time of approximately 300ns. The detector also showed sensitivity to neutrons. However, output signals were smaller than the expected voltage from the experiment using alpha-particles, probably because of charge accumulation from the high-neutron flux. (C) 2007 Elsevier B.V. All rights reserved.
  • F. Fujita, Y. Oshiki, J. H. Kaneko, A. Homma, K. Tsuji, K. Meguro, Y. Yamamoto, T. Imai, H. Watanabe, T. Teraji, S. Kawamura, M. Furusaka  DIAMOND AND RELATED MATERIALS  15-  (11-12)  1921  -1925  2006/11  [Not refereed][Not invited]
     
    A fast TOF measurement system with 150 ps time resolution for transport behavior of free charge carriers in an intrinsic diamond film by using a UV pulsed laser was developed. The 213 nm UV laser light narrowed to approximately 80 mu m widths could locally create hole-electron pairs in selected locations on a diamond film between two parallel electrodes on the surface. This system measured accurate charge transport characteristics in a diamond film, because created charge carriers moved in a part of the diamond film where they did not get any influence from the laser irradiation. Diamond samples used for verification of the TOF system were intrinsic CVD diamond films with thickness between 4 and 10 mu m grown on HP/HT diamond substrates. Transit time of holes for one diamond film was 4.7 ns with a traverse distance of 250 mu m. The local irradiation of laser made it possible to measure transport characteristics of electrons and holes separately. In addition, it substantially reduced the influence of photoelectron, because the laser beam did not irradiate electrodes. Through several examinations, excellent reliability of the TOF system was confirmed. (c) 2006 Elsevier B.V. All rights reserved.
  • Atsuhiko Ochi, Hironori Kiyamura, Junichi Kaneko, Hidetoshi Ohshita, Tohru Takeshita, Shuji Tanaka, Hiroyuki Iwasaki, Kentaro Ochiai, Makoto Nakao  REVIEW OF SCIENTIFIC INSTRUMENTS  77-  (10)  10E709  2006/10  [Not refereed][Not invited]
     
    Thin gap chamber (TGC) is a very thin multiwire proportional chamber of only a few millimeters. It has a quick response (about 20 ns), and its production costs are relatively low. TGCs have been used as large area detectors in high energy physics such as Large Electron-Positron collider (LEP) and will be used in the Large Hadron collider (LHC) experiment. However, the characteristics of TGCs under neutrons are not yet clearly understood. As the energy deposits of several MeV neutrons in TGCs are large, the possible effect of these deposits on the operation of the detector is a concern. We studied TGC performance in relation to efficiency, charge distribution, and operation stability using several gas mixtures (CO2/n-pentane and CF4/n-pentane) with 2.5 and 14 MeV neutron sources at Fusion Neutronics Source (FNS) in Japan Atomic Energy Agency. Operation stability using a CF4 based gas was more than 100 times greater than with CO2 based gas, while the minimum ionizing particle signal gain was almost the same. The detection efficiencies were around 0.1% (14 MeV) and 0.02% (2.5 MeV). These results are consistent with our simulation studies. (c) 2006 American Institute of Physics.
  • Y. Oshiki, J. H. Kaneko, F. Fujita, K. Hayashi, K. Meguro, A. Homma, S. Kawamura, Y. Yokota, Y. Yamamoto, K. Kobashi, T. Imai, T. Sawamura, M. Furusaka  DIAMOND AND RELATED MATERIALS  15-  (10)  1508  -1512  2006/10  [Not refereed][Not invited]
     
    Drift velocities of charge carriers in polycrystalline diamonds were measured by a self-triggered time-of-flight (TOF) method with alpha particles based on a radiation measurement technique. Based on these measured results, a synthesis method for polycrystalline diamond was verified, and the electric properties of polycrystalline diamonds were improved; drift velocity was increased from 5 x 10(2) to 3 x 10(4) cm/s. The mean free paths (MFPs) of capture of charge carriers in a CVD single crystal diamond was obtained by induced charge distribution measurements with alpha particles, and drift velocity was measured by another TOF method using. a UV pulsed laser. MFPs of capture of electron and hole in a CVD single crystal diamond were determined to be 5.4 and 9.6 mu m, respectively; the hole and electron drift velocities were 5 x 10(5) cm/s and 3 x 10(5) cm/s in an electric field of 24.4 kV/cm, respectively. For diamond, short transit times of several nanoseconds and short MFPs of capture in several micrometers were successfully obtained for the first time by combining of these methods. (c) 2005 Elsevier B.V. All rights reserved.
  • Investigation on possibility of PMN-PT single-crystal as neutron optical device
    Physica B  1277  -1279  2006  [Not refereed][Not invited]
  • Performance tests for Thin Gap Chamber under several MeV neutron sources
    Rev. Sci. Instrum  10E709  2006  [Not refereed][Not invited]
  • M Wakisaka, J Kaneko, F Fujita, K Ochiai, T Nishitani, S Yoshida, T Sawamura  NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT  554-  (1-3)  347  -355  2005/12  [Not refereed][Not invited]
     
    The process of neutron leaking from a 14 MeV neutron source facility was analyzed by calculations and experiments. The experiments were performed at the Fusion Neutron Source (FNS) facility of the Japan Atornic Energy Institute, Tokai-mura, Japan, which has a port on the roof for skyshine experiments, and a 3 He counter surrounded with a polyethylene moderator of different thicknesses was used to estimate the energy spectra and dose distributions. The He-3 counter with a 3-cm-thick moderator was also used for dose measurements, and the doses evaluated by the counter Counts and the calculated count-to-dose conversion factor agreed with the calculations to within similar to 30%. The dose distribution was found to fit a simple analytical expression, D(r) = Q(D) exp(-r/lambda(D))/r and the parameters Q(D) and lambda(D) are discussed. (c) 2005 Published by Elsevier B.V.
  • K Tsuji, K Hayashi, JH Kaneko, F Fujita, A Homma, Y Oshiki, T Sawamura, M Furusaka  DIAMOND AND RELATED MATERIALS  14-  (11-12)  2035  -2038  2005/11  [Not refereed][Not invited]
     
    UV position-sensitive sensor using a polycrystalline highly-oriented diamond film with a sensitive area of 2 x 4.5 mm(2) developed, and a proof-of-concept Study was conducted. The charge division method was employed to establish the position when the light hits the sensitive area. A fifth higher harmonic of a Nd:YAG laser with pulse width of 100 ps was used as a light source. The position resolution was 0.25 mm, and there was good position linearity throughout the sensitive area. Considering the possibility of light-spot broadening due to diffraction by the slit, the sensor may have a better resolution than that indicated by the result. But the electric-field strength of some parts of the crystal was insufficient, the response time was relatively slow, approximately 0.5 ins. (c) 2005 Elsevier B.V. All rights reserved.
  • JH Kaneko, T Tanaka, S Kawamura, Y Oshiki, K Tsuji, M Katagiri, K Ochiai, T Nishitani, F Fujita, T Sawamura, T Iida, M Furusaka  DIAMOND AND RELATED MATERIALS  14-  (11-12)  2027  -2030  2005/11  [Not refereed][Not invited]
     
    Radiation detector was made of a high-quality CVD polycrystalline diamond composed of frost column like structure diamond grains, and induced charge distribution spectra and drill velocities were measured by using alpha particles. As a result, the CVD polycrystalline achieved maximum induced charge of 83% of HP/HT type IIa diamond. Moreover, the CVD crystal had lower charge loss on electrons compared with the HP/HT type IIa diamond. Drift velocities of electrons and holes were nu(e)=7.7 x 10(4) and nu(h)=7.3 x 10(4) cm/s at an electric field of 20 kV/cm, respectively. In addition, response function measurement for 14 MeV neutrons was carried Out. (c) 2005 Elsevier B.V. All rights reserved.
  • T Tanaka, JH Kaneko, Y Kasugai, M Katagiri, H Takeuchi, T Nishitani, T Iida  DIAMOND AND RELATED MATERIALS  14-  (11-12)  2031  -2034  2005/11  [Not refereed][Not invited]
     
    Radiation tolerance of a type IIa synthetic diamond detector was examined from irradiation of mono-energetic 14 MeV neutrons. Measurements of I-V (current-voltage) characteristics and energy spectrum for 5.486 MeV alpha particles were performed after neutron irradiation. In the I-V characteristics measurement, enhancement of rectification was observed after neutron irradiation of up to 2.0 x 10(12) n/cm(2). Concurrently with the enhancement of rectification, significant decrease in signal amplitude was observed in energy spectrum measurement for alpha particles. It is considered that these changes were due to increase in the concentration of defects acting as shallow energy levels in the forbidden band. For neutron irradiation of higher than 1.6 x 10(13) n/cm(2), weakening of the rectification characteristics and recovery of the signal amplitude were observed. These changes imply that deep energy levels, which were also considered to be introduced by defects, were dominant and weakened the effects of the shallow energy levels. Increase in the concentration of the deep trapping levels resulted in gradual decrease of the signal amplitude and degradation in the energy resolution. The peak for the alpha particles was obtained up to 5.5 x 10(13) n/cm(2). (c) 2005 Elsevier B.V. All rights reserved.
  • F Fujita, A Homma, Y Oshiki, JH Kaneko, K Tsuji, K Meguro, Y Yamamoto, T Imai, T Teraji, T Sawamura, M Furusaka  DIAMOND AND RELATED MATERIALS  14-  (11-12)  1992  -1994  2005/11  [Not refereed][Not invited]
     
    There are continuing efforts of developing faster FETs and diamond is one of the strong candidates as a base semiconductor. Since the upper-limit-frequency of diamond FETs determines saturated drift velocities of charge-carriers, we need to first characterize diamond to develop better FETs. It is, however, not easy to measure the velocities with response time of less than 20 ns. Therefore, we developed a drift velocity measurement system using a time-of-flight (TOF) technique with a UV laser with 100 ps pulse width. In order to realize response times faster than 20 ns, we employed a 50 Omega coaxial cable as a load, with which we could effectively reduce the stray capacitance and inductance, and also, suppress reflections in the signal which gives false signals. As a result, we can measure carrier-transit times shorter than 10 ns. (c) 2005 Elsevier B.V. All rights reserved.
  • M Ishikawa, H Kumada, K Yamamoto, J Kaneko, G Bengua, H Unesaki, Y Sakurai, K Tanaka, T Kosako  NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT  551-  (2-3)  448  -457  2005/10  [Not refereed][Not invited]
     
    A wide range thermal neutron detector was developed based on the Scintillator with Optical Fiber (SOF) detector which has been previously used for thermal neutron monitoring during boron neutron capture therapy irradiation. With this new detector system we intended to address the issues of real-time thermal neutron flux measurement and the simultaneous measurement of a wide range of thermal neutron flux in a BNCT irradiation field which were difficult to implement with the gold wire activation method. The dynamic range of linearity of the SOF detector was expanded by using a plastic scintillator with a rapid decay time. On the other hand, the contribution of gamma rays and fast neutrons in the measured signals were compensated from those obtained by a pair of SOF detectors, one with a (LiF)-Li-6 neutron converter and the other without. The discrimination level for the measured signals was also optimized to further reduce the contribution of gamma rays and fast neutrons signals. A non-paralyzable system model was applied to correct for the dead-time in the detector system. A good agreement between the thermal neutron flux measured by the gold wire activation method and the paired SOF detector system was observed. However, measurements which would normally take a few days to perform with the gold wire activation method were obtained in just about 15 min using the SOF detector system. We also confirmed the dynamic range of linearity for the SOF detector system to be in the order of magnitude of 10(4). (c) 2005 Elsevier B.V. All rights reserved.
  • JH Kaneko, T Teraji, Y Hirai, M Shiraishi, S Kawamura, S Yoshizaki, T Ito, K Ochiai, T Nishitani, T Sawamura  REVIEW OF SCIENTIFIC INSTRUMENTS  75-  (10)  3581  -3584  2004/10  [Not refereed][Not invited]
     
    Response function measurement of layered-type chemical vapor deposition single crystal diamond radiation detectors for 14 MeV neutrons was carried out. The detector had a layered structure that was composed of a boron-doped diamond layer of 0.5 mum in thickness and a nondoped diamond layer of 20 mum on an inexpensive high pressure and high temperature-type Ib diamond substrate. The detector had energy resolution of 2.6% for 5.5 MeV alpha particles. This experiment was mainly carried out in order to understand the present status of the detector as a 14 MeV neutron spectrometer and an extent of charge trapping. As result, a peak caused by the C-12(n,alpha(0))Be-9 reactions was clearly observed; the best energy resolution of 6% as for a synthetic diamond radiation detector was achieved. Detection efficiency was 3.2x10(-7) counts/unit neutron fluence. However, taking the energy resolution for alpha particles, etc., into account, the energy resolution for 14 MeV neutrons was not so high. Further improvement based on better crystal growth is indispensable. (C) 2004 American Institute of Physics.
  • JH Kaneko, Y Otake, H Fujimoto, S Kawamura, M Watanabe, F Fujita, T Sawamura, P Mikula, M Furusaka  NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT  529-  (1-3)  166  -168  2004/08  [Not refereed][Not invited]
     
    A principle verification experiment of neutron electric optical devices using piezoelectric single crystals was carried out. This neutron electric optical device can change its d-spacing by applying an electric field to the crystal, which results in change of the Bragg diffraction angle. Although an alpha-quartz has a small piezoelectric strain constant, an alpha-quartz was used in this experiment because characteristics of alpha-quartz are well known and it is easy to obtain high quality and large size single crystals. At first, macroscopic distortion and change of thickness caused by an applied electric field were observed by using laser interferometers. Thus, double crystal diffraction measurement using 4.7 Angstrom cold neutrons was carried out. For these experiments, DC bias voltage was applied to the crystal. As a result, peaks of rocking curves were shifted 14s at 500 V and 2 min at 1000 V from their original positions. These values were approximately one figure larger than the theoretical values; therefore, these results were influenced by macroscopic bending of the crystal. From these results, it can be concluded that the possibility of neutron electric optical devices using not only change of d-spacing but also macroscopic bending of piezoelectric crystal was confirmed. (C) 2004 Elsevier B.V. All rights reserved.
  • JH Kaneko, N Susa, S Tsuchida, M Watanabe, S Miura, T Mizuno, Y Yamauchi, M Hashiba, T Oku, A Homma, F Fujita, T Ino, M Furusaka, T Sawamura, HM Shimizu, Y Kiyanagi  NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT  529-  (1-3)  307  -309  2004/08  [Not refereed][Not invited]
     
    A thin GSO scintillator was developed aiming at applications for the neutron science. In order to fabricate a large and thin GSO scintillator in the future, fabrication was started from two types of GSO powders. Although several GSO films were fabricated by evaporation techniques, these films did not have luminescence in photo luminescence (PL) spectroscopy. Thus, these samples were annealed up to 1550degreesC. However, it resulted in no luminescence observation. In response to these results, GSO powders were directly annealed; a phenomenon looking like melting and sintering were observed for Gd2Si2O7:Ce at a temperature higher than 1500degreesC. This sample was quasi-transparent and had luminescence at 405 nm in PL spectrum. In addition, this sample was tougher than a GSO single crystal. In conclusion, the prospect of fabrication of a thin GSO scintillator by combination of annealing and mechanical polishing was obtained. (C) 2004 Elsevier B.V. All rights reserved.
  • M Kitaichi, S Sawamura, M Wakisaka, JH Kaneko, K Ochiai, T Nishitani, T Sawamura  RADIATION PROTECTION DOSIMETRY  110-  (1-4)  731  -738  2004  [Not refereed][Not invited]
     
    In this study spatial and time distribution of neutrons leaking from Hokkaido University 45 MeV Electron Linac facility have measured and compared with the Monte Carlo simulations. The neutron transport processes inside and outside the facility building has been simulated using MCNP. The neutrons have measured by BF3 counters and He-3 counters with polyethylene moderators up to the distance of 330 in from the facility. The spatial distribution of ambient dose equivalent converted from the counts has been compared with the simulation. The distribution estimated from the counts by the BF3 counter has been shown fairly good agreement with the calculation. The spatial distribution of counts obtained at the 45 MeV Electron Linac facility has been compared with that obtained at the Fusion Neutronics Source (FNS) facility of JAERI. The difference between the propagation characteristics of neutrons leaking from those facilities has been discussed.
  • Measurement of behavior of charge carriers and investigation into charge-trapping mechanisms in high-purity type-IIa diamond single crystals grown by high-pressure and high-temperature synthesis
    JH Kaneko, T Tanaka, Y Tanimura, A Birumati, Y Hirai, M Katagiri, Y Ikeda, T Nishitani, H Takeuchi, T Iida, T Sawamura  NEW DIAMOND AND FRONTIER CARBON TECHNOLOGY  14-  (5)  299  -311  2004  [Not refereed][Not invited]
     
    The behavior of charge carriers in type-IIa single diamond crystals grown by high-pressure and high-temperature synthesis was observed using nuclear methods. The drift velocities of holes and electrons were measured by a time-of-flight method using a particles from an Am-241 source. Although the drift velocities of holes and electrons were 6.7 x 10(5) cm/s at 30 kV/cm and 6.5 x 10(5) cm/s at 15 kV/cm, respectively, these values are less than 1/10 of the drift velocities of top-grade, high-purity natural-type IIa diamond single crystals reported elsewhere. In addition, pulse-height spectra, i.e., induced-charge distribution, were measured with light illumination to determine the energy levels of trapping centers, and it was revealed that illumination with red light released trapped electrons. Moreover, it was observed that red light illumination facilitated the quick release of trapped holes. To explain these experimental results, the Fermi level and ionizing ratio of impurities were calculated. Results show that nitrogen works as a trapping center for electrons and boron works as a trapping center for holes; probably this center had trapping and detrapping effects on holes. However, it was confirmed that holes could not play the role of a trapping center for electrons. Moreover, it was revealed that another energy level was required for a trapping center for electrons. To explain all experimental results, an energy level 0.6 eV above the valence band was assumed in addition to the nitrogen and boron impurities. In this case, several ppm of acceptor-like centers are required to function as trapping centers for electrons.
  • S Yoshida, T Nishitani, K Ochiai, J Kaneko, J Hori, S Sato, M Yamauchi, R Tanaka, M Nakao, M Wada, M Wakisaka, Murata, I, C Kutsukake, S Tanaka, T Sawamura, A Takahashi  FUSION ENGINEERING AND DESIGN  69-  (1-4)  637  -641  2003/09  [Not refereed][Not invited]
     
    The D-T neutron skyshine experiments have been carried out at the Fusion Neutronics Source (FNS) of JAERI with the neutron yield of similar to 1.7 x 10(11) n/s. The concrete thickness of the roof and the wall of a FNS target room are 1.15 and 2 in. respectively. The FNS skyshine port with a size of 0.9 x 0.9 m(2) was open during the experimental period. The radiation dose rate outside the target room was measured a maximum distance of 550 in from the D-T target point with a spherical rem-counter. Secondary gamma-rays were measured with high purity Ge detectors and NaI scintillation counters. The highest neutron dose was about 9 x 10(-22) Sv/(source neutron) at a distance of 30 in from the D-T target point and the dose rate was attenuated to 4 x 10(-24) Sv/(source neutron) at a distance of 550 in. The measured neutron dose distribution was analyzed with Monte Carlo code MCNP-4B and a simple line source model. The MCNP calculation overestimates the neutron dose in the distance range larger than 230 m. The line source model agrees well with the experimental results within the distance of 350 m. (C) 2003 Elsevier Science B.V. All rights reserved.
  • T Sawamura, JH Kaneko, M Abe, M Tamura, Murai, I, A Homma, F Fujita, S Tsuda  NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT  505-  (1-2)  29  -32  2003/06  [Not refereed][Not invited]
     
    The response of superheated drop detectors or bubble detectors (BDs) was measured for quasi-monoenergetic neutron beams in the 40-75 MeV range and the effects of a lead-converter enclosing the detector introduced to extend the response to the high-energy region were discussed. The experiments were performed in the quasi-monoenergetic neutron beam field at the AVF cyclotron facility, TAKASAKI Ion Accelerator for Advanced Radiation Application (TIARA) of Japan Atomic Energy Research Institute(JAERI). Monte Carlo calculations by MCNPX code were carried out to estimate the lead-converter effect on neutron spectra in a detector exposed to 40-75 MeV quasi-monoenergetic source neutrons. The calculations indicated an increase in the energy ranges of the neutrons of 0.1-10 MeV and this can be expected to increase the number of bubbles produced in the detector. Experimental results showed that the sensitivity was lowered to about a half the nominal sensitivity and that a 3 cm thick lead-converter could compensate for the sensitivity decrease in the experimental energy region. (C) 2003 Elsevier Science B.V. All rights reserved.
  • JH Kaneko, T Tanaka, T Imai, Y Tanimura, M Katagiri, T Nishitani, H Takeuchi, T Sawamura, T Iida  NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT  505-  (1-2)  187  -190  2003/06  [Not refereed][Not invited]
     
    The first investigation of a radiation detector made of a diamond single crystal grown by a chemical vapor deposition (CVD) method was successfully carried out. The diamond single crystal, having a size of 2.0 x 2.0 x 0.7 mm(3), was grown by the CVD method and then applied to the detector. The CVD method was able to reduce nitrogen and boron impurities in diamond crystals more effectively than a high-pressure and high-temperature (HP/HT) method. Consequently the detector had high-energy resolution of 0.4% for 5.486 MeV alpha particles from an Am-241 source. The behavior of charge carriers in the detector could not be adequately investigated because the detector had a partial depression layer and strong rectification. Ionization energy of the CVD diamond was determined to be 16.1 eV; this value was higher than that of the HP/HT type IIa diamond, i.e., 13.1 eV. This result shows the potential of CVD diamond single crystals because an ideal diamond should have higher ionization energy than the HP/HT type IIa diamond that had the influence of impurities. (C) 2003 Elsevier Science B.V. All rights reserved.
  • Deposition of high quality diamond films for UV/radiation detectors
    Proceedings of the 10th International symposium on advanced materials  ISAM 2003-  65  -66  2003  [Not refereed][Not invited]
  • Evaluation of Neutrons Leaking from the Accelerator Facilities
    9th Conf. Neutron Dosimetry Dosimeter  0  2003  [Not refereed][Not invited]
  • Superheated Emulsion --- As High Energy Neutron
    The 9th Conf. Neutron Dosimetry Dosimeter  126  2003  [Not refereed][Not invited]
  • 西谷 健夫, 落合 謙太郎, 吉田 茂生, 田中 良平, 脇坂 雅志, 中尾 誠, 佐藤 聡, 山内 通則, 堀 順一, 高橋 亮人, 金子 純一, 澤村 晃子  J. Plasma and Fusion Research  79-  (3)  282  -289  2003  [Not refereed][Not invited]
  • Investigation on charge trapping mechanism in a high-purity HP/HT type IIa diamond single crystal using nuclear methods
    Proceedings of the 10th International symposium on advanced materials  ISAM 2003-  7  -8  2003  [Not refereed][Not invited]
  • Neutrons Leaked from a 45 MeV Linac Facility
    Proceedings of the 1st Asian Oceanic Congress for Radiation Protection (AOCRP-1)  0  2002  [Not refereed][Not invited]
  • In situ transmissivity measurements of KU1 quartz in the UV range under 14 MeV neutron irradiation
    J. Nucl. Materials  307  -311  2002  [Not refereed][Not invited]
  • C Konno, F Maekawa, Y Kasugai, Y Uno, J Kaneko, T Nishitani, M Wada, Y Ikeda, H Takeuchi  NUCLEAR FUSION  41-  (3)  333  -337  2001/03  [Not refereed][Not invited]
     
    A series of fusion neutronics experiments has been performed at the Fusion Neutronics Source facility at Japan Atomic Energy Research Institute as ITER EDA R&D tasks to find ways of dealing with various nuclear problems originating from 14 MeV neutrons in ITER. Recently three groups of experiments were carried out: (1) straight duct streaming experiments, (2) decay heat experiments, and (3) development of a fusion power monitor utilizing activation of water. The straight duct streaming experiments suggest that the calculation accuracy for straight duct streaming analyses in ITER nuclear designs is +/-40%. The decay heat experiments show that the accuracy of the decay heat calculation is within 10% for copper and type 316 stainless steel, while it is similar to 30% for tungsten. It is demonstrated that a fusion power monitor utilizing activation of water is applicable to ITER.
  • UNO Y, KANEKO J, NISHITANI T, MAEKAWA F, TANAKA T, SHIBATA S, IKEDA Y, KHRIPUNOV V, WALKER C  Fusion Eng. Des  56/57-  895  -898  2001  [Not refereed][Not invited]
  • Study on X-Rays and Neutrons Leaked from a 45 MeV Electron Linac Facility
    J. Korean Asso. Radiat. Prot  26-  (3)  133  -137  2001  [Not refereed][Not invited]
  • TANAKA T, KANEKO J, TAKEUCHI D, SUMIYA H, KATAGIRI M, NISHITANI T, TAKEUCHI H, IIDA T, OHKUSHI H  Rev. Sci. Instrum  72-  (2)  1406  -1410  2001  [Not refereed][Not invited]
  • J Kaneko, Y Uno, T Nishitani, F Maekawa, T Tanaka, Y Shibata, Y Ikeda, H Takeuchi  REVIEW OF SCIENTIFIC INSTRUMENTS  72-  (1)  809  -813  2001/01  [Not refereed][Not invited]
     
    As a part of development of nuclear instrumentation for the international thermonuclear experimental reactor (ITER), technical feasibility of a fusion power monitor based on activation of water flow was studied. The fusion power monitor determines D-T neutron yield, i.e., fusion power, by measuring 6.1 and 7.1 MeV gamma rays accompanied by disintegration of N-16 nuclei that are produced by the O-16(n,p) N-16 reactions with 14 MeV neutrons in water. The fusion power monitor consists of a water pipe loop laid from the first wall to the outside of the bioshield and a gamma -ray detector, e.g., a BGO scintillator. Fusion power can be measured in an absolute value by this monitor similar to a neutron activation method with a pneumatic tube system; in addition, this monitor has a feature that continuously measures the fusion power with time resolution faster than 1 s. This monitor also has other excellent features in terms of long-term stability, sensitivity only for D-T neutrons and being maintenance free. In order to confirm the technical feasibility of the fusion power monitor based on activation of water flow, experiments for dependence of N-16 gamma -ray yield on the velocity of water flow and for time response were carried out. It was found that the time response was described in a turbulent flow model, and time resolution of 50 ms that fully satisfied the time resolution of 100 ms required from plasma diagnostics was achieved. Furthermore, detection sensitivity of the fusion power monitor when it is applied to the ITER was estimated based on the experimental results; it was determined that the monitor had sufficiently high sensitivity. (C) 2001 American Institute of Physics.
  • KAWARABAYASHI J, MARDIYANTO M P, URITANI A, IGUCHI T, KANEKO J, TAKEUCHI H  IEEE Trans. Nucl. Sci  48-  (3,Pt.1)  527  -529  2001  [Not refereed][Not invited]
  • NAKA R, WATANABE K, KAWARABAYASHI J, URITANI A, IGUCHI T, HAYASHI N, KOJIMA N, YOSHIDA T, KAKUTA T  IEEE Trans. Nucl. Sci  48-  (6,Pt.2)  2348  -2351  2001  [Not refereed][Not invited]
  • J. Kaneko, Y. Uno,
    72-  (1)  809  -813  2001  [Not refereed][Not invited]
  • J Kaneko, C Yonezawa, Y Kasugai, H Sumiya, T Nishitani  DIAMOND AND RELATED MATERIALS  9-  (12)  2019  -2023  2000/12  [Not refereed][Not invited]
     
    Metallic impurities in high-purity type IIa and conventional type To diamond single crystals grown by high-pressure and high-temperature (HPHT) synthesis were determined by neutron activation analysis using thermal neutrons. Metallic impurities of Fe, Co, Cr and other minor elements were detected in the high-purity type IIa diamond crystal. The typical quantities of these metallic impurities were a few ppb. The influence of these metallic impurities on the electrical properties of the type IIa diamond crystal was practically negligible compared with nitrogen and boron impurities behaving as a donor and an acceptor, respectively. In addition to the impurities detected in the type IIa diamond crystal, Ni impurities of several hundreds of ppb were detected in conventional type Ib diamond crystals. A difference in molten metal solvents used in the synthesis of each diamond crystal resulted in the difference in metallic impurities. (C) 2000 Elsevier Science B.V. All rights reserved.
  • TANIMURA Y, KANEKO J, KATAGIRI M, IKEDA Y, NISHITANI T, TAKEUCHI H, IIDA T  Nucl. Instrum. Meth  443-  (2/3)  325  -330  2000  [Not refereed][Not invited]
  • C Mori, J Gotoh, A Uritani, H Miyahara, Y Ikeda, Y Kasugai, J Kaneko, M Sasao, Y Sakuma, K Kudo, N Takeda, T Iida  NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT  422-  (1-3)  75  -78  1999/02  [Not refereed][Not invited]
     
    A new type of fast neutron spectrometer composed of a CH4 proportional counter and a Si semiconductor detector which is called the counter telescope type was constructed for plasma-temperature diagnostics. The counting gas CH4 is used as a converter of neutrons to protons. Since the energy loss of the proton in the converter CH4 can be fairly precisely measured with the proportional counter, the energy resolution for the proton is high, so that a good energy resolution for neutrons is obtained. The energy resolution of the spectrometer itself excluding the energy spread of the D-T 14 MeV neutrons was 1.7% which seems to be the best so far, and the detection efficiency was 1 x 10(-6). If better energy resolution is preferable, even 0.5% is obtained and the efficiency in this case is 4 x 10(-8). (C) 1999 Elsevier Science B.V. All rights reserved.
  • KANEKO J, KATAGIRI M, IKEDA Y, NISHITANI T  Nucl. Instrum. and Meth  422-  (1/3)  211  -215  1999  [Not refereed][Not invited]
  • KANEKO J, IKEDA Y, NISHITANI T, KATAGIRI M  Rev. Sci. Instrum  70-  (1, Pt.2)  1100  -1103  1999  [Not refereed][Not invited]
  • KIMURA K, KANEKO J, SHARMA S, ITOH N  Nucl. Instrum and Meth  154-  (1/4)  318  -324  1999  [Not refereed][Not invited]
  • KIMURA K, KANEKO J, SHARMA S, HONG W, ITOH N  Phys. Rev. B  60-  (18)  12626  -12634  1999  [Not refereed][Not invited]
  • KIMURA K, HONG W, KANEKO J, ITOH N  Nucl. Instrum. and Meth  141-  (1/4)  425  -430  1998  [Not refereed][Not invited]
  • Development of Radiation Detectors using Synthetic Diamond Crystals
    Proceedings of the 5th NIRIM International symposium on advanced materials  ISAM '98-  257  -260  1998  [Not refereed][Not invited]
  • M Isobe, T Nishitani, AV Krasilnikov, J Kaneko, M Sasao  FUSION ENGINEERING AND DESIGN  34-35-  573  -576  1997/03  [Not refereed][Not invited]
     
    A natural diamond detector (NDD) is one of the candidates for the D-T neutron spectrometer in the International Thermonuclear Experimental Reactor since it has a high energy resolution, a high radiation resistance and a very compact size. The characteristic performance of NDD as a D-T neutron spectrometer was examined at the FNS neutron generator. The NDD indicated the energy resolution of 1.95% to 14.1 MeV neutrons. In order to obtain the information of the triton slowing-down, the NDD was applied to the deuterium discharges of the JT-60U tokamak. By accumulating the data of several shots, the change of the pulse height spectrum suggesting the slowing-down of tritons was observed after neutral beam turn-off. (C) 1997 Elsevier Science S.A.
  • T Iguchi, E Takada, M Nakazawa, J Kaneko, T Nishitani, T Matoba, Y Ikeda  FUSION ENGINEERING AND DESIGN  34-35-  585  -589  1997/03  [Not refereed][Not invited]
     
    A 14 MeV neutron spectrometer suitable for an ITER-like fusion reactor is conceptually designed on the basis of a recoil proton counter telescope method in oblique scattering geometry. To verify the principle and basic performance of the detector concept, preliminary experiments are made for a prototype detector system, where the detector responses are measured to 14 MeV neutrons produced from an accelerator deuterium-tritium (DT) neutron source and compared with the calculated ones. The comparison results show reasonably good agreement and demonstrate the possibility of energy resolution of 2.5% in full width at half maximum for 14 MeV neutron spectrometry. (C) 1997 Elsevier Science S.A.
  • KRASILNIKOV A V, KANEKO J, ISOBE M, MAEKAWA F, NISHITANI T  Rev. Sci. Instrum.  68-  (4)  1720  -1724  1997  [Not refereed][Not invited]
  • KANEKO J, KATAGIRI M, IKEDA Y, ARA K, IGUCHI T, NAKAZAWA M  Nucl. Instrum. and Meth.  385-  (1)  157  -160  1997  [Not refereed][Not invited]
  • KANEKO J, KATAGIRI M  Nucl. Instrum. and Meth  383-  (2/3)  547  -548  1996  [Not refereed][Not invited]
  • T IGUCHI, J KANEKO, M NAKAZAWA, T MATOBA, T NISHITANI, S YAMAMOTO  FUSION ENGINEERING AND DESIGN  28-  (1/4)  689  -698  1995/03  [Not refereed][Not invited]
     
    Neutron measurement in fusion experimental reactors is very important for burning plasma diagnostics and control, monitoring of irradiation effects on device components, neutron source characterization for in-situ engineering tests etc. A conceptual design of neutron diagnostic systems for an International Thermonuclear Experimental Reactor (ITER)-like fusion experimental reactor is made, which consists of a neutron yield monitor, a neutron emission profile monitor and a 14 MeV neutron spectrometer. Each of them is based on a unique idea to meet the required performances for full power conditions assumed at ITER operation. The final design results and expected performances of the promising neutron diagnostic systems are presented together with their critical design issues.
  • NEUTRON SPECTROMETERS FOR ITER
    Diagnostics for Experimental Thermonuclear Fusion Reactors, Proceedings of the International Workshop on Diagnostics for ITER, Aug. 28 - Sept. 1  0  1995  [Not refereed][Not invited]

Industrial Property Rights

  • 入力関数測定装置
    特許公開2011-64661
  • 小型X線発生装置
    特許公開2009-283169
  • 単結晶シンチレータ
    特願2008-050385
  • 動的腫瘍の放射線治療装置および動的腫瘍の放射線治療プログラムム(PCT/JP2008/052944)
    特願2007-041373
  • 中性子線検出器
    特開2004-184104
  • 高速・高位置分解能型中性子検出用ガスカウンタ計測システム
    特許公開2002-62360

Awards & Honors

  • 2008 日本原子力学会 放射線工学部会 奨励賞
  • 2008 Non

Research Grants & Projects

  • 医用原子力
    Date (from‐to) : 2004
  • Nuclear engineering for radiation therapy and diagnostics
    Date (from‐to) : 2004
  • 酸化物シンチレータの開発
    Date (from‐to) : 2001
  • development of oxide scintillators
    Date (from‐to) : 2001
  • 中性子散乱実験用中性子検出器・中性子光学素子の開発
    Date (from‐to) : 1999
  • Development of neutron detectors and neutron optics
    Date (from‐to) : 1999
  • 人工ダイヤモンド放射線検出器の開発
    Date (from‐to) : 1994
  • Development of synthetic diamond radiation detectors
    Date (from‐to) : 1994

Educational Activities

Teaching Experience

  • 一般教育演習(フレッシュマンセミナー)
    開講年度 : 2018
    課程区分 : 学士課程
    開講学部 : 全学
  • Inter-Graduate School Classes(General Subject):Humanities and Social Sciences
    開講年度 : 2018
    課程区分 : 修士課程
    開講学部 : 大学院共通科目
    キーワード : ビジネスプラン、財務分析、マーケティング、企業戦略、PBL
  • Inter-Graduate School Classes(General Subject):Humanities and Social Sciences
    開講年度 : 2018
    課程区分 : 修士課程
    開講学部 : 大学院共通科目
    キーワード : ビジネスシミュレーション、経営戦略、財務、マーケティング、損益分岐点計算、戦略的意思決定
  • Radiation and Quantum Beam Measurement
    開講年度 : 2018
    課程区分 : 修士課程
    開講学部 : 工学院
  • Radiation and Quantum Beam Measurement
    開講年度 : 2018
    課程区分 : 修士課程
    開講学部 : 工学院
    キーワード : 放射線計測、統計、ガス検出器、シンチレーション検出器、半導体検出器、スペクトル測定、中性子計測
  • Inter-Graduate School Classes(General Subject):Humanities and Social Sciences
    開講年度 : 2018
    課程区分 : 修士課程
    開講学部 : 大学院共通科目
    キーワード : アカウンティング、ファイナンス、財務諸表、財務諸表分析、キャッシュフロー、時間価値
  • Inter-Graduate School Classes(General Subject):Inter-Disciplinary Sciences
    開講年度 : 2018
    課程区分 : 修士課程
    開講学部 : 大学院共通科目
    キーワード : キャリアマネジメント(Career Management)、 研究マネジメント(Research Management)、MOT (Management of Technology)、すべての仕事に必要な基本スキル(Transferable Skills)、イノベーション (Innovation)、マーケティング(Marketing)、知的財産(Intellectual Property)、プレゼンテーション(Presentation)、アントレプレナーシップ(Entrepreneurship)、コンプライアンス(Compliance)、企業における研究開発(Industrial R&D)、リーダーシップ(Leadership)、グローバル人材(Global Human Resource)
  • Radiation and Quantum Beam Measurement
    開講年度 : 2018
    課程区分 : 博士後期課程
    開講学部 : 工学院
  • Radiation and Quantum Beam Measurement
    開講年度 : 2018
    課程区分 : 博士後期課程
    開講学部 : 工学院
    キーワード : 放射線計測、統計、ガス検出器、シンチレーション検出器、半導体検出器、スペクトル測定、中性子計測
  • Career Management Seminar
    開講年度 : 2018
    課程区分 : 博士後期課程
    開講学部 : 生命科学院
    キーワード : キャリアマネジメント(Career Management)、 研究マネジメント(Research Management)、MOT (Management of Technology)、すべての仕事に必要な基本スキル(Transferable Skills)、イノベーション (Innovation)、マーケティング(Marketing)、知的財産(Intellectual Property)、プレゼンテーション(Presentation)、アントレプレナーシップ(Entrepreneurship)、コンプライアンス(Compliance)、企業における研究開発(Industrial R&D)、リーダーシップ(Leadership)、グローバル人材(Global Human Resource)
  • Freshman Seminar
    開講年度 : 2018
    課程区分 : 学士課程
    開講学部 : 全学教育
    キーワード : ビジネスシミュレーション、経営戦略、財務、マーケティング、損益分岐点計算、戦略的意思決定
  • Atomic Physics
    開講年度 : 2018
    課程区分 : 学士課程
    開講学部 : 工学部
    キーワード : 原子、原子核、核反応、放射線、物質との相互作用、放射線防護
  • Freshman Seminar
    開講年度 : 2018
    課程区分 : 学士課程
    開講学部 : 全学教育
    キーワード : 放射線、放射能、放射線被ばく、放射線医療、原子炉、環境放射能、放射性廃棄物処理・処分、廃炉工学、オープン教材
  • Freshman Seminar
    開講年度 : 2018
    課程区分 : 学士課程
    開講学部 : 全学教育
    キーワード : 量子ビーム、プラズマ、触媒、ナノ材料

Campus Position History

  • 2017年4月1日 
    2019年3月31日 
    研究戦略室室員
  • 2017年4月1日 
    2019年3月31日 
    総長補佐
  • 2017年4月1日 
    2021年3月31日 
    産学・地域協働推進機構副機構長
  • 2019年4月1日 
    Present 
    研究戦略室室員
  • 2019年4月1日 
    Present 
    総長補佐

Position History

  • 2017年4月1日 
    2019年3月31日 
    研究戦略室室員
  • 2017年4月1日 
    2019年3月31日 
    総長補佐
  • 2017年4月1日 
    2021年3月31日 
    産学・地域協働推進機構副機構長
  • 2019年4月1日 
    Present 
    研究戦略室室員
  • 2019年4月1日 
    Present 
    総長補佐


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