Yogo, Akifumi*; Lan, Z.*; Arikawa, Yasunobu*; Abe, Yuki*; Mirfayzi, S. R.*; Wei, T.*; Mori, Takato*; Golovin, D.*; Hayakawa, Takehito*; Iwata, Natsumi*; et al.
Physical Review X, 13(1), p.011011_1 - 011011_12, 2023/01
Sato, Shunsuke*; Nauchi, Yasushi*; Hayakawa, Takehito*; Kimura, Yasuhiko; Kashima, Takao*; Futakami, Kazuhiro*; Suyama, Kenya
Journal of Nuclear Science and Technology, 9 Pages, 2022/10
A new non-destructive method for evaluating Cs activity in spent nuclear fuels was proposed and experimentally demonstrated for physical measurements in burnup credit implementation. Cs activities were quantified using gamma ray measurements and numerical detector response simulations without reference fuels, in which 137Cs activities are well known. Fuel samples were obtained from a lead use assembly (LUA) irradiated in a commercial pressurized water reactor (PWR) up to 53 GWd/t. Gamma rays emitted from the samples were measured using a bismuth germinate (BGO) scintillation detector through a collimator attached to a hot cell. The detection efficiency of gamma rays with the detector was calculated using the PHITS particle transport calculation code considering the measurement geometry. The relative activities of Cs, Cs, and Eu in the sample were measured with a high-purity germanium (HPGe) detector for more accurate simulations of the detector response for the samples. The absolute efficiency of the detector was calibrated by measuring a standard gamma ray source in another geometry. Cs activity in the fuel samples was quantified using the measured count rate and detection efficiency. The quantified Cs activities agreed well with those estimated using the MVP-BURN depletion calculation code.
Hayakawa, Takehito*; Toh, Yosuke; Kimura, Atsushi; Nakamura, Shoji; Shizuma, Toshiyuki*; Iwamoto, Nobuyuki; Chiba, Satoshi*; Kajino, Toshitaka*
Physical Review C, 103(4), p.045801_1 - 045801_5, 2021/04
Shizuma, Toshiyuki*; Minato, Futoshi; Omer, M.*; Hayakawa, Takehito*; Ogaki, Hideaki*; Miyamoto, Shuji*
Physical Review C, 103(2), p.024309_1 - 024309_8, 2021/02
Low-lying dipole transitions in Pb were measured via nuclear photon scattering using a quasi-monochromatic, linearly polarized photon beam. The electric () and magnetic () dipole strengths were extracted for excitation energies up to 6.8 MeV. The present (,) results, combined with (,) data from the literature, were used to investigate the and photoabsorption cross sections near the neutron separation energy by comparison with predictions of the particle-vibration coupling on top of the quasi-particle random phase approximation (PVC+QRPA).
Hatsukawa, Yuichi*; Hayakawa, Takehito*; Tsukada, Kazuaki; Hashimoto, Kazuyuki*; Sato, Tetsuya; Asai, Masato; Toyoshima, Atsushi; Tanimori, Toru*; Sonoda, Shinya*; Kabuki, Shigeto*; et al.
PLOS ONE (Internet), 13(12), p.e0208909_1 - e0208909_12, 2018/12
Imaging of Tc radioisotope was conducted using an electron tracking-Compton camera (ETCC). Tc emits 204, 582, and 835 keV rays, and was produced in the Mo(p,n)Tc reaction with a Mo-enriched target. The recycling of the Mo-enriched molybdenum trioxide was investigated, and the recycled yield of Mo was achieved to be 70% - 90%. The images were obtained with each of the three rays. Results showed that the spatial resolution increases with increasing -ray energy, and suggested that the ETCC with high-energy -ray emitters such as Tc is useful for the medical imaging of deep tissue and organs in the human body.
Shizuma, Toshiyuki*; Hayakawa, Takehito*; Daito, Izuru*; Ogaki, Hideaki*; Miyamoto, Shuji*; Minato, Futoshi
Physical Review C, 96(4), p.044316_1 - 044316_10, 2017/10
The low-lying dipole strength in Cr was measured in nuclear resonance fluorescence experiments using a quasi-monochromatic, linearly polarized photon beam. The parities of the excited dipole states were determined by the intensity asymmetry of resonantly scattered -rays with respect to the polarization plane of the incident photon beam. The summed magnetic dipole (M1) strength was determined as at excitation energies between 7.5 and 12.1 MeV; the summed electric dipole (E1) strength was obtained as fm. The observed M1 and E1 strengths were compared via random phase approximation calculations using the Skyrme interaction. The effects of 2 particle-2 hole configuration mixing and tensor force on dipole strength distributions were investigated.
Hayakawa, Takehito*; Toh, Yosuke; Huang, M.; Shizuma, Toshiyuki*; Kimura, Atsushi; Nakamura, Shoji; Harada, Hideo; Iwamoto, Nobuyuki; Chiba, Satoshi*; Kajino, Toshitaka*
Physical Review C, 94(5), p.055803_1 - 055803_6, 2016/11
Omer, M.; Hajima, Ryoichi*; Angell, C.*; Shizuma, Toshiyuki*; Hayakawa, Takehito*; Seya, Michio; Koizumi, Mitsuo
Proceedings of INMM 57th Annual Meeting (Internet), 9 Pages, 2016/07
Isotope-specific -rays emitted in the nuclear resonance fluorescence (NRF) process provide a good technique for a non-destructive detection and assay of nuclear materials. We are developing technologies relevant to -ray nondestructive detection and assay utilizing NRF. A Monte Carlo code to simulate NRF process is necessary for design and evaluation of NDA systems. We are developing NRFGeant4, a Geant4-based simulation code, for this purpose. In NRF experiments, highly-enriched targets are generally used such that the NRF signals are dominant and easily measured. In contrast, a real situation may involve very small contents of isotopes of interest. This results in a difficulty in measuring NRF signals because of the interference with other interactions, e.g. elastic scattering. For example, a typical nuclear fuel pellet contains about 90% of U as a host material and less than 1% of Pu as an isotope of interest. When measuring NRF of Pu, there would be a huge background coming from the elastic scattering of U. Therefore, an estimation of the elastic scattering with the host material is essential for precise determination of isotope of interest. Satisfying estimation of elastic scattering is currently not available except for some calculations. In the present study, we upgrade our simulation code to include the calculation of elastic scattering events.
Hajima, Ryoichi; Sawamura, Masaru; Nagai, Ryoji; Nishimori, Nobuyuki; Hayakawa, Takehito; Shizuma, Toshiyuki; Angell, C.
Proceedings of 12th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.79 - 83, 2015/09
Generation of energy-tunable narrow-bandwidth -rays via Laser Compton Scattering (LCS) is of great interest for scientific studies and applications of MeV photons which interact with nuclei. We are developing technologies relevant to generation of high-brightness LCS -ray beams. One of the promising applications of such -rays is the nondestructive detection and assay of nuclides which are necessary for nuclear security and safeguards. We summarize R-and-D status of LCS -ray sources and overview future applications.
Shizuma, Toshiyuki; Hajima, Ryoichi; Hayakawa, Takehito; Angell, C.; Seya, Michio
Proceedings of 37th ESARDA Annual Meeting (Internet), p.838 - 845, 2015/08
Nondestructive assay (NDA) of nuclear materials is an important technology for nuclear security and safeguard applications. We have proposed an NDA system based on nuclear resonance fluorescence (NRF). In the proposed detection system, an energy-tunable and mono-energetic -ray source generated by Compton scattering of laser light (laser Compton scattering; LCS) with high-energy electrons is used. The NRF measurement can be more efficient by using a mono-energetic -ray beam, which has been demonstrated in recent NRF measurements. We have started a research and development program of the LCS -ray NDA systems, which includes demonstration of LCS -ray generation from an energy recovery linac (ERL), establishment of detection system, and benchmark of Monte Carlo simulation. The R&D status including recent results on the demonstrations of the LCS photon generation as well as the measurement principles will be reported.
Angell, C.; Hayakawa, Takehito; Shizuma, Toshiyuki; Hajima, Ryoichi; Quiter, B. J.*; Ludewigt, B. L.*; Karwowski, H. J.*; Rich, G.*; Silano, J.*
Proceedings of INMM 56th Annual Meeting (Internet), 9 Pages, 2015/07
Negm, H.*; Ogaki, Hideaki*; Daito, Izuru*; Hayakawa, Takehito; Zen, H.*; Kii, Toshiteru*; Masuda, Kai*; Hori, Toshitada*; Hajima, Ryoichi; Shizuma, Toshiyuki; et al.
Journal of Nuclear Science and Technology, 52(6), p.811 - 820, 2015/06
The dependence of the nuclear resonance fluorescence (NRF) yield on the target thickness was studied. To this end, an NRF experiment was performed on U using a laser Compton back-scattering (LCS) -ray beam at the High Intensity -ray Source facility at Duke University.
Matsuba, Shunya*; Hayakawa, Takehito; Shizuma, Toshiyuki; Nishimori, Nobuyuki; Nagai, Ryoji; Sawamura, Masaru; Angell, C.; Fujiwara, Mamoru; Hajima, Ryoichi
Japanese Journal of Applied Physics, 54(5), p.052203_1 - 052203_5, 2015/05
Angell, C.; Hajima, Ryoichi; Hayakawa, Takehito; Shizuma, Toshiyuki; Karwowski, H.*; Silano, J.*
Nuclear Instruments and Methods in Physics Research B, 347, p.11 - 19, 2015/03
Hajima, Ryoichi; Shizuma, Toshiyuki; Nagai, Ryoji; Mori, Michiaki; Hayakawa, Takehito; Angell, C.; Seya, Michio
Kaku Busshitsu Kanri Gakkai (INMM) Nihon Shibu Dai-35-Kai Nenji Taikai Rombunshu (Internet), 7 Pages, 2015/01
no abstracts in English
Angell, C.; Hayakawa, Takehito; Shizuma, Toshiyuki; Hajima, Ryoichi; Quiter, B. J.*; Ludewigt, B. L.*; Karwowski, H.*; Rich, G.*
Nuclear Physics and -ray sources for Nuclear Security and Nonproliferation, p.133 - 141, 2014/12
Angell, C.; Hajima, Ryoichi; Hayakawa, Takehito; Shizuma, Toshiyuki; Karwowski, H.*; Silano, J.*
Physical Review C, 90(5), p.054315_1 - 054315_6, 2014/11
Horikawa, Ken*; Miyamoto, Shuji*; Mochizuki, Takayasu*; Amano, So*; Li, D.*; Imasaki, Kazuo*; Izawa, Yasukazu*; Ogata, Kazuyuki*; Chiba, Satoshi*; Hayakawa, Takehito
Physics Letters B, 737, p.109 - 113, 2014/10
It was predicted in 1950's, the neutron angular distribution in (, n) reactions with a 100% linearly polarized -ray beam should be anisotropic and described by a simple function of a + b sin at 90 on the beam axis but it has not been experimentally confirmed for middle-heavy nuclides over than half a century. We have verified experimentally this angular distribution on Au, I, and natural Cu using linearly polarized laser Compton scattering -rays at NewSUBARU.
Hayakawa, Takehito; Fujiwara, Mamoru*
Nihon Genshiryoku Gakkai-Shi ATOMO, 56(7), p.448 - 452, 2014/07
It is considered that progress of nuclear security is important in the world. A key technology for nuclear security is non-destructive measurements of hidden nuclear materials and radioactive isotopes in various conditions. For such purpose, we require helps of professional in wide range fields as nuclear physics, accelerator science, laser science, and nuclear fusion science etc. outside of the traditional nuclear engineering.
Hajima, Ryoichi; Ferdows, M.; Hayakawa, Takehito; Shizuma, Toshiyuki; Kando, Masaki; Daito, Izuru*; Negm, H.*; Ogaki, Hideaki*
Proceedings of 5th International Particle Accelerator Conference (IPAC '14) (Internet), p.1943 - 1945, 2014/07