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Journal Articles

Integral test of international reactor dosimetry and fusion file on graphite assembly with DT neutron at JAEA/FNS

Ota, Masayuki; Sato, Satoshi; Ochiai, Kentaro; Konno, Chikara

Fusion Engineering and Design, 98-99, p.1847 - 1850, 2015/10

 Times Cited Count:2 Percentile:22.25(Nuclear Science & Technology)

International Reactor Dosimetry and Fusion File release 1.0 (IRDFF 1.0), has been released from the International Atomic Energy Agency (IAEA) recently. In order to validate and test IRDFF 1.0, IAEA has initiated a new Co-ordinated Research Project (CRP). Under this CRP, we have performed an integral experiment on a graphite pseudo-cylindrical slab assembly with DT neutron source at JAEA/FNS. The graphite assembly of 31.4 cm in equivalent radius and 61 cm in thickness is placed at a distance of about 20 cm from the DT neutron source. A lot of foils for the dosimetry reactions in IRDFF1.0 are inserted into the small spaces between the graphite blocks along the center axis of the assembly. After DT neutron irradiation, reaction rates for the dosimetry reactions are measured by the foil activation technique. This experiment is analyzed by using Monte Carlo neutron transport code MCNP5-1.40 with recent nuclear data libraries of ENDF/B-VII.1, JEFF-3.2, and JENDL-4.0. The experimental assembly and DT neutron source are modeled precisely in the MCNP calculation. The reaction rates calculated with IRDFF 1.0 as the response functions for the dosimetry reactions are compared with the experimental values. Also the calculations with JENDL Dosimetry File 99 (JENDL/D-99) are performed for comparison. The results calculated with IRDFF 1.0 show good agreement with the experimental results.

Journal Articles

Assessment of human body surface and internal dose estimations in criticality accidents based on experimental and computational simulations

Sono, Hiroki; Ono, Akio*; Kojima, Takuji; Takahashi, Fumiaki; Yamane, Yoshihiro*

Journal of Nuclear Science and Technology, 43(3), p.276 - 284, 2006/03

 Times Cited Count:1 Percentile:10.64(Nuclear Science & Technology)

For a study on the applicability of a personal dosimetry method to criticality accident dosimetry, an assessment of the human body surface and internal dose estimations was performed by experimental and computational simulations. The experimental simulation was carried out in a criticality accident situation at the TRACY facility. The neutron and $$gamma$$-ray absorbed doses in muscle tissue were separately estimated by a dosimeter set of an alanine dosimeter and a thermoluminescence dosimeter made of enriched lithium tetra borate with a phantom. The computational simulation was conducted with a Monte Carlo code taking account of dose components of neutrons, prompt $$gamma$$-rays and delayed $$gamma$$-rays. The computational simulation was ascertained to be valid by comparison between the calculated dose distributions in the phantom and the measured ones. The assessment based on the experimental and computational simulations confirmed that the personal dosimetry using the dosimeter set provided a first estimation of the body surface and internal doses with precision.

Journal Articles

Development of three kinds of tissue substitutes for a physical phantom in neutron dosimetry

Tsuda, Shuichi; Endo, Akira; Yamaguchi, Yasuhiro

Journal of Nuclear Science and Technology, 42(10), p.877 - 887, 2005/10

 Times Cited Count:2 Percentile:18.81(Nuclear Science & Technology)

Three kinds of tissue substitutes were synthesized in order to develop a physical phantom for neutron dosimetry. The optimal elemental compositions and densities were determined using a Monte Carlo simulation method, based on absorbed dose distributions of neutrons of a few MeV in various materials. The characteristics of the synthesized tissue substitutes were verified by absorbed dose measurements using monoenergetic neutron sources and a $$^{252}$$Cf neutron source. It was found that the developed tissue substitutes, NAN-, HAI- and HONE-JAERI, have tissue equivalence to actual tissues within 10 % accuracy for neutrons in most of common fast neutron fields.

Journal Articles

Application of invasion mathematical model in dosimetry for boron neutron capture therapy for malignant glioma

Yamamoto, Kazuyoshi; Kumada, Hiroaki; Nakai, Kei*; Endo, Kiyoshi*; Yamamoto, Tetsuya*; Matsumura, Akira*

Proceedings of 11th World Congress on Neutron Capture Therapy (ISNCT-11) (CD-ROM), 14 Pages, 2004/10

A dose distribution considered the tumor cell density distribution is required on the radiation therapy. We propose a novel method of determining target region considering the tumor cell concentration as a new function for the next generation Boron Neutron Capture Therapy (BNCT) dosimetry system. It has not been able to sufficiently define the degree of microscopic diffuse invasion of the tumor cells peripheral to a tumor bulk in malignant glioma using current medical imaging. Referring to treatment protocol of BNCT, the target region surrounding the tumor bulk has been set as the region which expands at the optional distance with usual 2cm margin from the region enhanced on T1 weighted gadolinium Magnetic Resonance Imaging (MRI). In this research, the cell concentration of the region boundary of the target was discussed by using tumor cell diffusion model in the sphere spatio-temporal system. The survival tumor cell density distribution after the BNCT irradiation was predicted by the two regions diffusion model for a virtual brain phantom.

Journal Articles

Development of neutron-monitor detector using liquid organic scintillator coupled with $$^{6}$$Li+ZnS(Ag) sheet

Sato, Tatsuhiko; Endo, Akira; Yamaguchi, Yasuhiro; Takahashi, Fumiaki

Radiation Protection Dosimetry, 110(1-4), p.255 - 261, 2004/09

 Times Cited Count:8 Percentile:50.96(Environmental Sciences)

For monitoring of neutron doses in high-energy accelerator facilities, we have developed a neutron-monitor detector applicable to energies from the thermal energy to 100 MeV. The detector is composed of a cylindrical (12.7 cm in diameter and 12.7 cm in length) liquid organic scintillator BC501A covered with $$^{6}$$Li+ZnS(Ag) sheets. Characteristics of this phoswitch-type detector were studied experimentally in moderated neutron fields of $$^{241}$$Am-Be and $$^{252}$$Cf sources, and in quasi-monoenergetic neutron fields of 40 and 70 MeV. It was found from the experiments that the detector is enough sensitive to both thermal and fast neutrons, and has an excellent property of pulse-shape discrimination between them. We concluded, therefore, that the detector can be used for monitoring of neutron doses over a wide energy range from the thermal to 100 MeV.

Journal Articles

Energy dependence of absorbed dose distributions in a soft tissue substitute for neutron dosimetry

Tsuda, Shuichi; Endo, Akira; Yamaguchi, Yasuhiro

Journal of Nuclear Science and Technology, 41(Suppl.4), p.132 - 135, 2004/03

A solid material improved in hydrogen and oxygen contents was synthesized for development of a physical phantom for neutron. The elemental composition and density are aimed for those of the soft tissue in ICRU Report 44. The soft tissue equivalence has been verified by an absorbed dose measurement using a 252Cf neutron source. In the present work, absorbed doses were measured for the purpose of examinations of the characteristic of the synthesized soft tissue substitute for neutron of various energies, using mono-energetic 0.565 MeV neutrons from $$^{7}$$Li(p,n) reaction and 5 MeV from D(d,n) reaction, and quasi-mono-energetic ones (40 and 65 MeV) produced via $$^{7}$$Li(p,n) reaction. The measured absorbed doses were compared with those calculated by Monte Carlo simulation codes. The results indicate that the tissue substitute has a characteristic of soft tissue equivalence for neutron in the energy range from several hundred keV up to approximately 100 MeV.

Journal Articles

Development of neutron-monitor detectors applicable to energies from thermal to 100MeV

Endo, Akira; Kim, E.; Yamaguchi, Yasuhiro; Sato, Tatsuhiko; Yoshizawa, Michio; Tanaka, Susumu; Nakamura, Takashi; Rasolonjatovo, A. H. D.*

Journal of Nuclear Science and Technology, 41(Suppl.4), p.510 - 513, 2004/03

no abstracts in English

Journal Articles

Synthesis and characterization of a soft-tissue substitute for neutron dosimetry

Tsuda, Shuichi; Endo, Akira; Yamaguchi, Yasuhiro

Journal of Nuclear Science and Technology, 40(12), p.1027 - 1031, 2003/12

 Times Cited Count:1 Percentile:11.39(Nuclear Science & Technology)

To develop a physical phantom for neutron dosimetry, a solid soft-tissue substitute was synthesized. The hydrogen and oxygen compositions of the synthesized tissue substitute, NAN-JAERI, are similar to those of the soft tissue in ICRU Report 44. To examine the radiation characteristics of the new soft-tissue substitute, absorbed dose distributions in NAN-JAERI were measured using a $$^{252}$$Cf neutron source. The measured absorbed dose distributions of neutrons and photons agree with those calculated by a Monte Carlo simulation code MCNP. The agreement between the experiment and the simulation verifies this method of evaluating the soft-tissue equivalence of NAN-JAERI for $$^{252}$$Cf neutrons. Similar simulations for some mono-energetic neutron sources showed that the newly developed tissue substitute has soft-tissue equivalent characteristics in the neutron energy range up to 14 MeV, in terms of the absorbed dose distributions in a slab phantom.

Journal Articles

Verification of the JAERI Computational Dosimetry System (JCDS) for boron neutron capture therapy

Kumada, Hiroaki; Yamamoto, Kazuyoshi; Torii, Yoshiya; Matsumura, Akira*; Nakagawa, Yoshinobu*

Japanese Journal of Medical Physics, Vol.23, Supplement 3, p.292 - 295, 2003/09

no abstracts in English

JAEA Reports

Development of the JAERI Computational Dosimetry System (JCDS) for boron neutron capture therapy (Cooperative research)

Kumada, Hiroaki; Yamamoto, Kazuyoshi; Torii, Yoshiya; Matsumura, Akira*; Yamamoto, Tetsuya*; Nose, Tadao*; Nakagawa, Yoshinobu*; Kageji, Teruyoshi*; Uchiyama, Junzo

JAERI-Tech 2003-002, 49 Pages, 2003/03

JAERI-Tech-2003-002.pdf:5.22MB

no abstracts in English

JAEA Reports

Proceedings of the 3rd Workshop on Dosimetry for External Radiations; November 28-29, 2002, Japan Atomic Energy Research Institute, Tokai, Ibaraki, Japan

Yoshizawa, Michio; Endo, Akira

JAERI-Conf 2003-002, 166 Pages, 2003/03

JAERI-Conf-2003-002.pdf:9.79MB

The present report is Proceedings of the Third Workshop on Dosimetry for External Radiations, held at the Tokai Research Establishment, Japan Atomic Energy Research Institute (JAERI), in November 28-29, 2002. The proceedings comprises 16 papers and a summary of general discussion. The Third Workshop, subtitled "On an opportunity of the completion of the facility of calibration standards for neutron at JAERI", focused on neutron dosimetry and included presentations on the status of international neutron standards, the development of calibration techniques of neutron dosimeters using accelerator neutron sources, and dosimetry for high-energy neutrons. The workshop identified the directions for the future research and development in this field.

Journal Articles

Dosimetry plan at the first irradiation test in the HTTR

Shibata, Taiju; Kikuchi, Takayuki; Shimakawa, Satoshi

Reactor Dosimetry in the 21st Century, p.211 - 218, 2003/00

The High Temperature Engineering Test Reactor (HTTR) is the first HTGR in Japan with a maximum power of 30 MW. The construction of it was completed successfully in March 2002. The HTTR aims to perform irradiation studies at its very wide irradiation spaces at high temperatures. Although the creep behavior of materials is measured by the large standard size specimens at out-of-pile, small size ones are generally used for in-pile creep tests because of the irradiation capability of reactors. The I-I type irradiation equipment, the first rig for the HTTR, is to be used for the in-pile creep test on a stainless steel with the standard specimens. The rig can give big tensile loads of about 9.8 kN on them. The temperatures of 550 and 600$$^{circ}$$C and the fast neutron fluence of 1.2$$times$$10$$^{23}$$n/m$$^{2}$$ are the targets of the test. Prior to the in-pile creep test, the in-core irradiation properties at the irradiation region are to be obtained by the rig as the first irradiation test. This paper describes the dosimetry plan at the first irradiation test and the subsequent data assessment procedure.

JAEA Reports

Production of a faithful realistic phantom to human head and thermal neutron flux measurement on the brain surface (Cooperative research)

Yamamoto, Kazuyoshi; Kumada, Hiroaki; Kishi, Toshiaki; Torii, Yoshiya; Endo, Kiyoshi*; Yamamoto, Tetsuya*; Matsumura, Akira*; Uchiyama, Junzo; Nose, Tadao*

JAERI-Tech 2002-092, 23 Pages, 2002/12

JAERI-Tech-2002-092.pdf:5.22MB

Thermal neutron flux is determined using the gold wires in current BNCT irradiation, so evaluation of arbitrary points after the irradiation is limited in the quantity of these detectors. In order to make up for the weakness, dose estimation of a patient is simulated by a computational dose calculation supporting system. In another way without computer simulation, a medical irradiation condition can be replicate experimentally using of realistic phantom which was produced from CT images by rapid prototyping technique. This phantom was irradiated at a same JRR-4 neutron beam as clinical irradiation condition of the patient and the thermal neutron distribution on the brain surface was measured in detail. This experimental evaluation technique using a realistic phantom is applicable to in vitro cell irradiation experiments for radiation biological effects as well as in-phantom experiments for dosimetry under the nearly medical irradiation condition of patient.

JAEA Reports

User's manual of a supporting system for treatment planning in boron neutron capture therapy; JAERI computational dosimetry system

Kumada, Hiroaki; Torii, Yoshiya

JAERI-Data/Code 2002-018, 158 Pages, 2002/09

JAERI-Data-Code-2002-018.pdf:30.28MB

A boron neutron capture therapy (BNCT) with epithermal neutron beam is expected to treat effectively for malignant tumor that is located deeply in the brain. It is indispensable to estimate preliminarily the irradiation dose in the brain of a patient in order to perform the epithermal neutron beam BNCT. Thus, the JAERI Computational Dosimetry System (JCDS), which can calculate the dose distributions in the brain, has been developed. JCDS is a software that creates a 3-dimentional head model of a patient by using CT and MRI images and that generates a input data file automaticly for calculation neutron flux and gamma-ray dose distribution in the brain by the Monte Carlo code: MCNP, and that displays the dose distribution on the head model for dosimetry by using the MCNP calculation results. JCDS has any advantages as follows; By treating CT data and MRI data which are medical images, a detail three-dimensional model of patinet's head is able to be made easily. The three-dimensional head image is editable to simulate the state of a head after its surgical processes such as skin flap opening and bone removal for the BNCT with craniotomy that are being performed in Japan. JCDS can provide information for the Patient Setting System to set the patient in an actual irradiation position swiftly and accurately. This report describes basic design and procedure of dosimetry, operation manual, data and library structure for JCDS (ver.1.0)

Journal Articles

Comparison of dosimetry by the realistic patient head phantom and by the patient's brain, and the JCDS calculation; A Clinical dosimetry study

Endo, Kiyoshi*; Matsumura, Akira*; Yamamoto, Tetsuya*; Nose, Tadao*; Yamamoto, Kazuyoshi; Kumada, Hiroaki; Kishi, Toshiaki; Torii, Yoshiya; Kashimura, Takanori*; Otake, Shinichi*

Research and Development in Neutron Capture Therapy, p.425 - 430, 2002/09

Using the Rapid Prototyping Technique, we produced a realistic phantom as a formative model of a patient head. This realistic phantom will contribute to verification of our planning system. However, cross-correlation among the calculations using the JAERI Computational Dosimetry System (JCDS), the realistic phantom, and the in vivo measurements were not fully completed because of the difficulty involved in modeling a post-surgical brain and a thermal neutron shield. The experimental simulation technique using the realistic phantom is a useful tool for more reliable dose planning for the intraoperative BNCT.

Journal Articles

In-air radiobiological dosimetry of JRR-4 neutron beams for boron neutron capture therapy

Yamamoto, Tetsuya*; Matsumura, Akira*; Yamamoto, Kazuyoshi; Kumada, Hiroaki; Hori, Naohiko; Torii, Yoshiya; Endo, Kiyoshi*; Matsushita, Akira*; Yoshida, Fumiyo*; Shibata, Yasushi*; et al.

Research and Development in Neutron Capture Therapy, p.697 - 700, 2002/09

The RBE of dose components generated in boron neutron capture therapy (BNCT) were separately determined in neutron beams at JRR-4. The cell killing effect of the neutron beam with or without the presence of 10B was highly dependent on the neutron beam used, according to the epithermal and fast neutron content in the beam. RBE (BARBEboron) values of the boron capture reaction for an epithermal (ENB), a mixed thermal-epithermal (TNB-1), and a thermal (TNB-2) neutron beams were 3.99$$pm$$0.24, 3.04$$pm$$0.19 and 1.43$$pm$$0.08, respectively.

Journal Articles

An Application to Intraoperative BNCT using epithermal neutron of new JRR-4 mode "Epi-12"

Matsushita, Akira*; Yamamoto, Tetsuya*; Matsumura, Akira*; Nose, Tadao*; Yamamoto, Kazuyoshi; Kumada, Hiroaki; Torii, Yoshiya; Kashimura, Takanori*; Otake, Shinichi*

Research and Development in Neutron Capture Therapy, p.141 - 143, 2002/09

A thermal-epithermal mixed beam "Thermal Neutron Beam Mode I" was used in the eleven sessions of boron neutron capture therapy which have been performed at JRR-4 from 1998. We are planning to use an epithermal beam for the treatment of deeper tumors in the next trial of the intraoperative BNCT. In this study, "Epi-12" which was made by putting up a cadmium shutter of "Thermal Neutron Beam Mode I" was investigated for the clinical benefits and safety by epithermal beams. Decrease of fast neutron contamination ratio in Epi-12 mode is the advantage for BNCT, particular in the intraoperative BNCT. Because fast neutron on the brain surface is one of the critical factors in the intraoperative BNCT in which the plain beam directly interacts the normal structures. Furthermore a mixture of mode Epi-12 and Th-12 will provide various dose distribution designs. It may be used as a new method to control the best distribution for individual tumors.

Journal Articles

Core calculation of the JMTR using MCNP

Nagao, Yoshiharu

JAERI-Conf 2000-018, p.156 - 167, 2001/01

no abstracts in English

JAEA Reports

Integral test of JENDL Dosimetry File 99 with high flux neutron field

Shimakawa, Satoshi

JAERI-Data/Code 99-043, p.75 - 0, 1999/09

JAERI-Data-Code-99-043.pdf:3.38MB

no abstracts in English

Journal Articles

Fusion dosimetry based on nuclear heating measurement with microcalorimeters

Ikeda, Yujiro; A.Kumar*

Proc. of 9th Int. Symp. on Reactor Dosimetry, 0, p.881 - 888, 1998/00

no abstracts in English

33 (Records 1-20 displayed on this page)