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Journal Articles

Characterization of the PTW 34031 ionization chamber (PMI) at RCNP with high energy neutrons ranging from 100 - 392 MeV

Theis, C.*; Carbonez, P.*; Feldbaumer, E.*; Forkel-Wirth, D.*; Jaegerhofer, L.*; Pangallo, M.*; Perrin, D.*; Urscheler, C.*; Roesler, S.*; Vincke, H.*; et al.

EPJ Web of Conferences, 153, p.08018_1 - 08018_5, 2017/09

 Times Cited Count:0 Percentile:0.03

At CERN, gas-filled ionization chambers PTW-34031 (PMI) are commonly used in radiation fields including neutrons, protons and $$gamma$$-rays. A response function for each particle is calculated by the radiation transport code FLUKA. To validate a response function to high energy neutrons, benchmark experiments with quasi mono-energetic neutrons have been carried out at RCNP, Osaka University. For neutron irradiation with energies below 200 MeV, very good agreement was found comparing the FLUKA simulations and the measurements. In addition it was found that at proton energies of 250 and 392 MeV, results calculated with neutron sources underestimate the experimental data due to a non-negligible gamma component originating from the target $$^{7}$$Li(p,n)Be reaction.

Journal Articles

Shielding experiments of concrete and iron for the 244 MeV and 387 MeV quasi-mono energetic neutrons using a Bonner sphere spectrometer (at RCNP, Osaka Univ.)

Matsumoto, Tetsuro*; Masuda, Akihiko*; Nishiyama, Jun*; Iwase, Hiroshi*; Iwamoto, Yosuke; Satoh, Daiki; Hagiwara, Masayuki*; Yashima, Hiroshi*; Yashima, Hiroshi*; Shima, Tatsushi*; et al.

EPJ Web of Conferences, 153, p.08016_1 - 08016_3, 2017/09

 Times Cited Count:0 Percentile:61.28

Neutron energy spectra behind concrete and iron shields were measured for quasi-monoenergetic neutrons above 200 MeV using a Bonner sphere spectrometer (BSS). Quasi-monoenergetic neutrons were produced by the $$^{7}$$Li(p,xn) reaction with 246-MeV and 389-MeV protons. The response function of BSS was also measured at neutron energies from 100 MeV to 387 MeV. In data analysis, the measured response function was used and the multiple neutron scattering effect between the BSS and the shielding material was considered. The neutron energy spectra behind the concrete and iron shields were obtained by the unfolding method using the MAXED code. Ambient dose equivalents were obtained as a function of a shield thickness successfully. For the case of the 244 MeV neutron incidence, the multiple neutron scattering effect on the effective dose is large under 50 cm thickness of the concrete shield.

Journal Articles

Applicability of the two-angle differential method to response measurement of neutron-sensitive devices at the RCNP high-energy neutron facility

Masuda, Akihiko*; Matsumoto, Tetsuro*; Iwamoto, Yosuke; Hagiwara, Masayuki*; Satoh, Daiki; Sato, Tatsuhiko; Iwase, Hiroshi*; Yashima, Hiroshi*; Nakane, Yoshihiro; Nishiyama, Jun*; et al.

Nuclear Instruments and Methods in Physics Research A, 849, p.94 - 101, 2017/03

 Times Cited Count:0 Percentile:10.71(Instruments & Instrumentation)

Quasi-monoenergetic high-energy neutron fields induced by $$^{7}$$Li(p,n) reactions are used for the response evaluation of neutron-sensitive devices. The quasi-monoenergetic high-energy field consists of high-energy monoenergetic peak neutrons and unwanted continuum neutrons down to the low-energy region. A two-angle differential method has been developed to compensate for the effect of the continuum neutrons in the response measurements. In this study, the two-angle differential method was demonstrated for Bonner sphere detectors, which are typical examples of moderator-based neutron-sensitive detectors, to investigate the method's applicability and its dependence on detector characteristics. Through this study, the adequacy of the two-angle differential method was experimentally verified, and practical suggestions were made pertaining to this method.

Journal Articles

Nitric oxide-mediated bystander signal transduction induced by heavy-ion microbeam irradiation

Tomita, Masanori*; Matsumoto, Hideki*; Funayama, Tomoo; Yokota, Yuichiro; Otsuka, Kensuke*; Maeda, Munetoshi*; Kobayashi, Yasuhiko

Life Sciences in Space Research, 6, p.36 - 43, 2015/07

A radiation-induced bystander response is generally known as a cellular response induced in unirradiated cell by receiving bystander signaling factors released from directly irradiated cells of a cell population. Bystander responses induced by high-LET heavy ions at low fluence are an important problem concerning the health of astronauts in the space environment. Here we set out NO-mediated bystander signal transductions induced by high-LET heavy-ion microbeam irradiation in normal human fibroblasts. Our findings suggest that Akt- and NF-$$kappa$$B-dependent signaling pathway involving COX-2 plays an important role in the NO-mediated high-LET heavy-ion-induced bystander responses. Additionally, COX-2 may be used as a molecular marker of high-LET heavy-ion-induced bystander cells, which are distinguish form directly irradiated cells.

Journal Articles

Mechanisms for the induction of radioadaptive response by radiation-induced bystander response

Matsumoto, Hideki*; Tomita, Masanori*; Otsuka, Kensuke*; Hatashita, Masanori*; Maeda, Munetoshi*; Funayama, Tomoo; Yokota, Yuichiro; Suzuki, Michiyo; Sakashita, Tetsuya; Ikeda, Hiroko; et al.

JAEA-Review 2014-050, JAEA Takasaki Annual Report 2013, P. 76, 2015/03

The objective of this project is to elucidate molecular mechanisms for the induction of radioadaptive response through radiation-induced bystander responses induced by irradiation with heavy ion microbeams in JAEA. We found that the adaptive response was induced by Ar (520 MeV $$^{40}$$Ar$$^{14+}$$) microbeam-irradiation of a limited number of cells, followed by the broad beam-irradiation and that the adaptive response was almost completely suppressed by the addition of carboxy-PTIO, as a nitric oxide (NO) scavenger. In addition, we found several genes induced specifically and preferentially when radioadaptive response could be induced. We confirmed that ${it iNOS}$ expression was specifically induced only when radioadaptive response could be induced. Our findings strongly suggested that radioadaptive response can be induced by NO-mediated bystander responses evoked by irradiation with heavy ion microbeams.

Journal Articles

Analysis of bystander response in 3D cultured tissue induced by heavy-ion microbeam irradiation

Tomita, Masanori*; Matsumoto, Hideki*; Otsuka, Kensuke*; Funayama, Tomoo; Yokota, Yuichiro; Suzuki, Michiyo; Sakashita, Tetsuya; Kobayashi, Yasuhiko

JAEA-Review 2014-050, JAEA Takasaki Annual Report 2013, P. 77, 2015/03

Radiation-induced bystander responses are defined as responses in cells that have not been directly targeted by radiation but are in the neighborhood of cells that have been directly exposed. In this study, we aim to clarify a role of bystander response to sustain the homeostasis of damaged tissue using heavy-ion microbeams. We established the heavy-ion microbeam irradiation method to a 3D cultured human epidermis. Using this method, a viable cell rate of the 3D cultured human epidermis irradiated with 260 MeV $$^{20}$$Ne-ion microbeams or broadbeams was analyzed by the MTT method.

Journal Articles

Measurement of neutron energy spectra behind shields for quasi-monoenergetic neutrons generated by 246-MeV and 389-MeV protons using a Bonner sphere spectrometer

Matsumoto, Tetsuro*; Masuda, Akihiko*; Nishiyama, Jun*; Harano, Hideki*; Iwase, Hiroshi*; Iwamoto, Yosuke; Hagiwara, Masayuki*; Satoh, Daiki; Yashima, Hiroshi*; Nakane, Yoshihiro; et al.

Progress in Nuclear Science and Technology (Internet), 4, p.332 - 336, 2014/04

Recently, many high-energy accelerators are used for various fields. Shielding data for high-energy neutrons are therefore very important from the point of view of radiation protection in high energy accelerator facilities. However, the shielding experimental data for high energy neutrons above 100 MeV are very poor both in quality and in quantity. In this study, neutron penetration spectral fluence and ambient dose through iron and concrete shields were measured with a Bonner sphere spectrometer (BSS). Quasi-monoenergetic neutrons were produced by the $$^{7}$$Li(p,xn) reaction by bombarding a 1-cm thick Li target with 246-MeV and 389-MeV protons in the Research Center for Nuclear Physics (RCNP) of the Osaka University. Shielding materials are iron blocks with a thickness from 10 cm to 100 cm and concrete blocks with a thickness from 25 cm to 300 cm.

Journal Articles

Response measurement of a Bonner sphere spectrometer for high-energy neutrons

Masuda, Akihiko*; Matsumoto, Tetsuro*; Harano, Hideki*; Nishiyama, Jun*; Iwamoto, Yosuke; Hagiwara, Masayuki*; Satoh, Daiki; Iwase, Hiroshi*; Yashima, Hiroshi*; Nakamura, Takashi*; et al.

IEEE Transactions on Nuclear Science, 59(1), p.161 - 166, 2012/02

 Times Cited Count:11 Percentile:66.72(Engineering, Electrical & Electronic)

In this study, responses of Bonner sphere spectrometer (BSS) for 245 and 388 MeV neutrons was measured at RCNP, Osaka University. The neutrons are generated in the $$^{7}$$Li(p,n) reaction and its spectra consist of a high-energy peak and a continuum down to the low energy. Therefore, the observed counts of BSS caused by the continuum need to be subtracted. Adjusting a Li target angle and a collimator position, 0 deg and 30 deg component of generated neutron are available. While the 0 deg component contains both the peak and the continuum, the 30 deg component is considered to contain only the continuum. Therefore, the response of the peak is obtained. The spectra were measured using the time-of-flight (TOF) method with a NE213 scintillator.

Journal Articles

Establishment of neutron fluence monitoring techniques for quasi-monoenergetic neutron calibration fields of high energy at TIARA

Shikaze, Yoshiaki; Tanimura, Yoshihiko; Saegusa, Jun; Tsutsumi, Masahiro; Uchida, Yoshiaki*; Yoshizawa, Michio; Harano, Hideki*; Matsumoto, Tetsuro*; Mizuhashi, Kiyoshi

JAEA-Review 2010-065, JAEA Takasaki Annual Report 2009, P. 158, 2011/01

no abstracts in English

Journal Articles

Photodisintegration of $$^{80}$$Se as a probe of neutron capture for the s-process branch-point nucleus $$^{79}$$

Makinaga, Ayano*; Hohara, Shinya*; Utsunomiya, Hiroaki*; Goko, Shinji*; Kaihori, Takeshi*; Akimune, Hidetoshi*; Yamagata, Tamio*; Goriely, S.*; Toyokawa, Hiroyuki*; Harano, Hideki*; et al.

Proceedings of Science (Internet), 28, p.239_1 - 239_4, 2010/12

no abstracts in English

Journal Articles

Recent progress in the energy recovery linac project in Japan

Sakanaka, Shogo*; Akemoto, Mitsuo*; Aoto, Tomohiro*; Arakawa, Dai*; Asaoka, Seiji*; Enomoto, Atsushi*; Fukuda, Shigeki*; Furukawa, Kazuro*; Furuya, Takaaki*; Haga, Kaiichi*; et al.

Proceedings of 1st International Particle Accelerator Conference (IPAC '10) (Internet), p.2338 - 2340, 2010/05

Future synchrotron light source using a 5-GeV energy recovery linac (ERL) is under proposal by our Japanese collaboration team, and we are conducting R&D efforts for that. We are developing high-brightness DC photocathode guns, two types of cryomodules for both injector and main superconducting (SC) linacs, and 1.3 GHz high CW-power RF sources. We are also constructing the Compact ERL (cERL) for demonstrating the recirculation of low-emittance, high-current beams using above-mentioned critical technologies.

Journal Articles

Photodisintegration of $$^{80}$$Se; Implications for the s-process branching at $$^{79}$$Se

Makinaga, Ayano*; Utsunomiya, Hiroaki*; Goriely, S.*; Kaihori, Takeshi*; Goko, Shinji*; Akimune, Hidetoshi*; Yamagata, Tamio*; Toyokawa, Hiroyuki*; Matsumoto, Tetsuro*; Harano, Hideki*; et al.

Physical Review C, 79(2), p.025801_1 - 025801_8, 2009/02

 Times Cited Count:22 Percentile:79.7(Physics, Nuclear)

Photoneutron cross sections were measured for $$^{80}$$Se immediately above the neutron separation energy with quasimonochromatic $$gamma$$-ray beams to experimentally constrain the E1 $$gamma$$ strength function for $$^{79}$$Se. Two sets of the $$gamma$$ strength function and the level density that equally meet the experimental constraint predict largely different neutron capture cross sections for $$^{79}$$Se. Based on the Maxwell-averaged cross sections of the latest compilation complemented with the predicted cross sections for $$^{79}$$Se, we calculated $$sigma$$N values of the main s-process component using a phenomenological model and deduced empirical abundances of the weak s-process component.

Journal Articles

Photoneutron cross sections for $$^{80}$$Se; Implications for the s-process thermometer

Makinaga, Ayano*; Utsunomiya, Hiroaki*; Kaihori, Takeshi*; Yamagata, Tamio*; Akimune, Hidetoshi*; Goriely, S.*; Toyokawa, Hiroyuki*; Matsumoto, Tetsuro*; Harano, Hideki*; Harada, Hideo; et al.

Nuclear Physics A, 805(1-4), p.564 - 566, 2008/06

Photoneutron cross sections were measured for $$^{80}$$Se near the neutron threshold energy with quasi-monochromatic $$gamma$$ rays. Using the $$^{80}$$Se($$gamma$$,$$n$$) cross section as experimental constraints on the E1 $$gamma$$ strength function, we estimate the neutron capture rates for $$^{79}$$Se. The solar abundance ratio of s-only nuclides $$^{80}$$Kr and $$^{82}$$Kr are analyzed in terms of the s-process branching at $$^{79}$$Se within the local approximation. The corresponding temperature and neutron density regimes are discussed in the light of the s-process scenario in massive stars.

Journal Articles

Discussions in Symposium "Neutron dosimetry in neutron fields; From detection techniques to medical applications"

Tanimura, Yoshihiko; Sato, Tatsuhiko; Kumada, Hiroaki; Terunuma, Toshiyuki*; Sakae, Takeji*; Harano, Hideki*; Matsumoto, Tetsuro*; Suzuki, Toshikazu*; Matsufuji, Naruhiro*

Hoshasen, 34(2), p.135 - 139, 2008/04

Recently the traceability system (JCSS) of neutron standard based on the Japanese law "Measurement Act" has been instituted. In addition, importance of the neutron dose evaluation has been increasing in not only the neutron capture medical treatment but also the proton or heavy particle therapy. Against such a background, a symposium "Neutron dosimetry in neutron fields; From detection techniques to medical applications" was held on March 29, 2008 and recent topics on the measuring instruments and their calibration, the traceability system, the simulation technique and the medical applications were introduced. This article summarizes the key points in the discussion at the symposium.

Journal Articles

Intercellular and intracellular signaling pathways mediating ionizing radiation-induced bystander effects

Hamada, Nobuyuki*; Matsumoto, Hideki*; Hara, Takamitsu*; Kobayashi, Yasuhiko

Journal of Radiation Research, 48(2), p.87 - 95, 2007/03

 Times Cited Count:177 Percentile:94.93(Biology)

Experimental evidence has accumulated demonstrating that biological effects of ionizing radiation arise in non-irradiated bystander cells that have received signals from near or distant irradiated cells. This phenomenon has been termed the radiation-induced bystander effect and challenges the long-held tenet that cell nucleus is the quintessential target for radiation damage. Bystander effects encompass a range of endpoints, such as genetic and epigenetic alterations, changes in gene expression, signal transduction pathway activation, and late-arising effects in their descendants. Proposed mechanisms involve gap junctional cell-to-cell communication, transmissible soluble factors, oxidative stress, lipid rafts, and calcium fluxes. In this article, we review proposed mechanisms underpinning the bystander effect and also briefly discuss the potential benefit of bystander effects in cancer radiotherapy.

Journal Articles

Vanguards of paradigm shift in radiation biology; Radiation-induced adaptive and bystander responses

Matsumoto, Hideki*; Hamada, Nobuyuki*; Takahashi, Akihisa*; Kobayashi, Yasuhiko; Onishi, Takeo*

Journal of Radiation Research, 48(2), p.97 - 106, 2007/03

 Times Cited Count:120 Percentile:90.34(Biology)

The risks of low dose ionizing irradiation ($$<$$ 100 mSv) have been estimated using a linear no-threshold model by extrapolating from data obtained after high dose irradiation. The validity of this dose-response model is, however, controversial because evidence accumulated for over the past decade has shown that response of living organisms including humans to low dose/low dose-rate radiation is different from that to high dose/high dose-rate radiation. In another words, findings that cannot be explained by the classical "target theory" of radiobiology have accumulated. The radiation-induced adaptive response, bystander effects, low-dose radio-hypersensitivity, and genomic instability are specifically observed in response to low dose/low dose-rate radiation, and underpinnings of these responses often involve biochemical/molecular signals responding to targeted and non-targeted events. Recently, interrelations between the radioadaptive and bystander responses have been increasingly reported. We review observations supporting the existence of the latter two phenomena, and discuss the possible link between them from the aspect of production of reactive oxygen and nitrogen species.

Journal Articles

Analysis of molecular mechanisms for radiation-induced bystander effects using heavy ion microbeams

Matsumoto, Hideki*; Hatashita, Masanori*; Takahashi, Akihisa*; Hamada, Nobuyuki*; Wada, Seiichi*; Funayama, Tomoo; Sakashita, Tetsuya; Kakizaki, Takehiko; Kobayashi, Yasuhiko

JAEA-Review 2006-042, JAEA Takasaki Annual Report 2005, P. 111, 2007/02

Journal Articles

Photoneutron cross section measurement for $$^{94}$$Zr using laser inverse Compton $${gamma}$$ rays

Hohara, Shinya*; Goko, Shinji*; Makinaga, Ayano*; Kaihori, Takeshi*; Toyokawa, Hiroyuki*; Utsunomiya, Hiroaki*; Hara, Kaoru; Kitatani, Fumito; Harada, Hideo; Matsumoto, Tetsuro*; et al.

JAEA-Conf 2006-009, p.66 - 69, 2006/11

no abstracts in English

JAEA Reports

Evaluation of prediction accuracy for $$^{238}$$U Doppler effect measured in FCA LWR simulating cores; Analysis with JENDL-3.3 library and SRAC system (Joint research)

Kawasaki, Kenji*; Ando, Masaki; Okajima, Shigeaki; Fukushima, Masahiro; Nakano, Makoto*; Matsumoto, Hideki*

JAEA-Research 2006-008, 40 Pages, 2006/03

JAEA-Research-2006-008.pdf:3.6MB

Analysis was performed to evaluate prediction accuracy of a neutronics code system for thermal reactor; the SRAC system with the use of the latest nuclear data library JENDL-3.3 for the $$^{238}$$U Doppler effect measured in the uranium fueled (FCA-XXI-1D2) and MOX fueled (XXII-1 series) cores. The results of the analysis with the diffusion theory showed overestimation by up to +11%. In relatively soft neutron spectra, however, the calculated values agreed with the experimental ones within the experimental errors.

JAEA Reports

Study on the prediction accuracy of nuclide generation and depletion with JENDL

Okumura, Keisuke; Oki, Shigeo*; Yamamoto, Munenari*; Matsumoto, Hideki*; Ando, Yoshihira*; Tsujimoto, Kazufumi; Sasahara, Akihiro*; Katakura, Junichi; Matsumura, Tetsuo*; Aoyama, Takafumi*; et al.

JAERI-Research 2004-025, 154 Pages, 2005/01

JAERI-Research-2004-025.pdf:19.46MB

This report summarizes the activity (FY2000-2003) of Working Group (WG) on Evaluation of Nuclide Generation and Depletion under Subcommittee on Nuclear Fuel Cycle of Japanese Nuclear Data Committee. In the WG, analyses of Post Irradiation Examinations have been carried out for UO$$_{2}$$ and MOX fuels irradiated in PWRs, BWRs and FBRs, and for actinide samples irradiated in fast reactors, by using ORIGEN or more detailed calculation codes with their libraries based on JENDL-3.2, JENDL-3.3 and other foreign nuclear data files. From these results, current prediction accuracy and problems for evaluation of nuclide generation and depletion are discussed. Furthermore, this report covers other products of our activity; development of the ORIGEN libraries for PWR, BWR and FBR based on JENDL-3.3, study on introduction of neutron spectrum index to ORIGEN calculations, and results of questionnaire survey on desirable accuracy of ORIGEN calculations.

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