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Characteristics of the 2012 model lithium-6 time-analyzer neutron detector (LiTA12) system as a high efficiency detector for resonance absorption imaging

甲斐 哲也; 佐藤 節夫*; 廣井 孝介; Su, Y.; 瀬川 麻里子; Parker, J. D.*; 松本 吉弘*; 林田 洋寿*; 篠原 武尚; 及川 健一; et al.

Physica B; Condensed Matter, 551, p.496 - 500, 2018/12

 パーセンタイル:100(Physics, Condensed Matter)

The 2012 model lithium-6 time-analyzer neutron detector (LiTA12) system, based on a lithium glass scintillator and multi-anode photomultiplier tube, has the highest neutron efficiency among the detectors for pulsed neutron imaging together with a flexibility of the efficiency by changing the thickness of the lithium glass. The authors expect this detector system could become a main detector system for the energy-resolved neutron imaging system, RADEN, at J-PARC, and have started evaluation of the LiTA12 system. For example, spatial resolution for resonance absorption imaging was evaluated by using a line-pair pattern made by 3 micro meter thick gold on a quartz plate. Less than 1 mm width line pairs were resolved at an 8 Mcps neutron counting rate and around 5 eV neutron energy.


Reliability estimation of neutron resonance thermometry using tantalum and tungsten

甲斐 哲也; 廣井 孝介; Su, Y.; 篠原 武尚; Parker, J. D.*; 松本 吉弘*; 林田 洋寿*; 瀬川 麻里子; 中谷 健; 及川 健一; et al.

Physics Procedia, 88, p.306 - 313, 2017/06

 被引用回数:1 パーセンタイル:8.64

Neutron resonance thermometry, which measures material temperature by analyzing the Doppler broadening of a neutron resonance peak, is one of the applications of energy-resolved neutron imaging at RADEN of J-PARC. Although this technique is promising, advantages and disadvantages have not been discussed in practical applications. The authors measured neutron transmission rates of tantalum and tungsten foils in a heater chamber up to 300 degrees Celsius at RADEN. The energy-dependent neutron transmission rates with different statistics were obtained after the measurements by selecting arbitrary measuring intervals from one measurement, and the temperatures of the foils were estimated from those transmission rates with different statistics. The reliability of the neutron resonance thermometry with statistical accuracy, irradiation time and spatial resolution are discussed.


Development of a pulsed neutron three-dimensional imaging system using a highly sensitive image-intensifier at J-PARC

瀬川 麻里子; 大井 元貴; 甲斐 哲也; 篠原 武尚; 呉田 昌俊; 坂本 健作; 伊巻 正*

Nuclear Instruments and Methods in Physics Research A, 769, p.97 - 104, 2015/01

 パーセンタイル:100(Instruments & Instrumentation)

In order to realize neutron energy resolved three-dimensional (3D) imaging at resonance neutron energy region, a camera system coupled with a high sensitive and high frame-rate gating image-intensifier was developed. The resonance absorption 3D imaging was successfully demonstrated at pulsed neutron source of Japan Proton Accelerator Research Complex (J-PARC). The camera system allowed us to obtain a Time-of-flight (TOF) image of 2352 (W) $$times$$ 1726 (H) pixels resolved into a narrow energy range. The 3D images having enhanced contrast at corresponding resonance energy regions for cylindrical Au, Ta and In samples were reconstructed by "Convolution Filtered Back-Projection (FBP)" and "Maximum Likelihood Expectation Maximization (MLEM)" methods. And qualities of spatial resolutions in the depth direction were evaluated to be about 1 mm experimentally. The results obtained in the present experiments showed that the system could have the ability to adjust the practical use in the industrial field.



呉田 昌俊; 瀬川 麻里子

ぶんせき, 2014(6), p.283 - 289, 2014/06



Measurements of neutron capture cross section for $$^{207,208}$$Pb

瀬川 麻里子; 藤 暢輔; 原田 秀郎; 北谷 文人; 小泉 光生; 深堀 智生; 大島 真澄*; 岩本 信之; 岩本 修; 初川 雄一; et al.

AIP Conference Proceedings 1594, p.339 - 344, 2014/05

Pb isotopes represent a sensitive test for models of $$s$$-process nucleosynthesis, since the decomposition of the complex abundance pattern in these mass regions is difficult to be accounted for by classical $$s$$-process model. Main neutron capture processes, the $$s$$- and $$r$$-processes, attribute to the origin of the isotopes in this mass region. As the aspects of neutron sources of the $$s$$-process, Gallino et al. reported that $$^{13}$$C($$alpha$$, n) neutron source which is burning radiatively at $$kT$$ = 8 keV play an important role on $$s$$-process nucleosynthesis. Hence, in the present study, an anti-Compton NaI(Tl) spectrometer and highly enriched samples are used to determine the $$gamma$$-ray energy spectra from the (n, $$gamma$$) reaction. This NaI(Tl) spectrometer makes it possible to detect the discrete $$gamma$$-ray from the reaction to the low-lying states in $$^{207,208}$$Pb. We give results both neuron capture cross sections for $$^{207,208}$$Pb to obtain the pulse height spectra using NaI(Tl) spectrometer with time of flight method in the wide neutron energy range from 10 to 100 keV. The Maxwellian averaged capture cross sections for $$^{207,208}$$Pb are determined in the astrophysical relevant energy region.


Neutron resonance imaging of a Au-In-Cd alloy for the JSNS

大井 元貴; 勅使河原 誠; 甲斐 哲也; 原田 正英; 前川 藤夫; 二川 正敏; 橋本 英子*; 瀬川 麻里子; 呉田 昌俊; Tremsin, A.*; et al.

Physics Procedia, 43, p.337 - 342, 2013/04

 被引用回数:3 パーセンタイル:12.82



New production routes for medical isotopes $$^{64}$$Cu and $$^{67}$$Cu using accelerator neutrons

金 政浩*; 永井 泰樹; 岩本 信之; 湊 太志; 岩本 修; 初川 雄一; 瀬川 麻里子; 原田 秀郎; 今野 力; 落合 謙太郎; et al.

Journal of the Physical Society of Japan, 82(3), p.034201_1 - 034201_8, 2013/03

 被引用回数:22 パーセンタイル:18.64(Physics, Multidisciplinary)

分子イメージングと核医学治療に期待されている放射性同位体$$^{64}$$Cuと$$^{67}$$Cuの生成断面積を14MeVの加速器中性子を用い測定した。この結果とZn同位体の断面積評価値を用いて、40MeVで5mAの重陽子ビームによる$$^{nat}$$C(d,n)反応からの速中性子を用いて生成される$$^{64}$$Cuと$$^{67}$$Cuの量を計算した。$$^{64}$$Cuの生成量は、12時間照射で175gの$$^{64}$$Znについて1.8テラベクレルであり、$$^{67}$$Cuの生成量は2日間の照射で、$$^{67}$$Zn(n,p)$$^{67}$$Cu反応では184g $$^{67}$$Znに対して249ギガベクレルであり、$$^{68}$$Zn(n,x)$$^{68}$$Cuでは186g $$^{68}$$Znに対して287ギガベクレルである。以上より、$$^{67}$$Cuの生成には、極微量不純物放射性同位体しか生成しない$$^{68}$$Zn(n,x)$$^{68}$$Cu反応を新しく提唱した。また、$$^{64}$$Cuの生成には、$$^{64}$$Zn(n,p)$$^{64}$$Cu反応が期待できる反応であることを示した。



呉田 昌俊; 瀬川 麻里子

自動車技術会シンポジウムテキスト, No.9-11, p.24 - 29, 2012/01



Development of a high-speed camera system for neutron imaging at a pulsed neutron source

瀬川 麻里子; 甲斐 哲也; 酒井 卓郎; 大井 元貴; 呉田 昌俊

Nuclear Instruments and Methods in Physics Research A, 697, p.77 - 83, 2012/01

 被引用回数:10 パーセンタイル:22.62(Instruments & Instrumentation)

A neutron energy resolved imaging system with a time-of-flight technique has been newly developed and installed at Japan Proton Accelerator Research Complex (J-PARC) with the aim to investigate more preciously and rapidly a spatial distribution of several elements and crystals in various kinds of materials or substances. A high-speed video camera (CMOS, 1300 k frame/sec) equipped system allows to obtain TOF images consecutively resolved into narrow energy ranges with a single pulsed neutrons while conventional CCD camera imaging system could obtain only one TOF image in an arbitral neutron energy region in the pulsed neutron energy region from 0.01 eV to a few keV. Qualities of the images obtained with the system, such as spatial resolution (defined by modulation transfer function, 0.8 line-pairs/mm at En 0.01 eV), dependence of the brightness on the neutron energy and measurement errors ($$sim$$2%) of the system were examined experimentally and evaluated by comparison with those of conventional imaging system. The results obtained in the experiments show that the system can visualize the neutron energy resolved images within a small error even at high speed.


Visualization of blurry images of liquid by multi-scale analysis

宮村 浩子; 呉田 昌俊; 瀬川 麻里子; 久保 純*; 斎藤 隆文*; 鈴木 喜雄; 武宮 博

Visualization of Mechanical Processes (Internet), 1(3), 8 Pages, 2011/10



First demonstration of neutron resonance absorption imaging using a high-speed video camera in J-PARC

甲斐 哲也; 瀬川 麻里子; 大井 元貴; 橋本 英子; 篠原 武尚; 原田 正英; 前川 藤夫; 及川 健一; 酒井 卓郎; 松林 政仁; et al.

Nuclear Instruments and Methods in Physics Research A, 651(1), p.126 - 130, 2011/09

 被引用回数:8 パーセンタイル:34.47(Instruments & Instrumentation)



Isotope production for medical usage using fast neutron reactions

初川 雄一; 永井 泰樹; 金 政浩; 瀬川 麻里子; 原田 秀郎; 岩本 修; 岩本 信之; 落合 謙太郎; 高倉 耕祐; 今野 力; et al.

Proceedings in Radiochemistry, 1(1), p.327 - 329, 2011/09

核医学において最もよく用いられている$$^{99}$$Tcの供給は危機に面しており、新たな製造プロセスの開発は喫緊の問題である。本研究は$$^{rm 99m}$$TcをFNSより発生される14MeV高速中性子を用いて効率よく製造することを提案するものであり、試験的に作成したチタン酸ゲルを用いた$$^{rm 99m}$$Tc/$$^{99}$$Moジェネレータについても併せて発表を行う。


Design of a 4$$pi$$ LaBr$$_{3}$$(Ce) spectrometer for neutron capture cross section measurements

後藤 淳*; 原田 秀郎; 北谷 文人; 永井 泰樹; 大島 真澄; 瀬川 麻里子; 藤 暢輔

Journal of the Korean Physical Society, 59(2), p.1585 - 1588, 2011/08

 被引用回数:2 パーセンタイル:75.59(Physics, Multidisciplinary)




呉田 昌俊; 瀬川 麻里子; 高峰 潤

可視化情報学会誌, 31(122), p.116 - 121, 2011/07



Visualization of blurred images of liquid by multi-scale analysis

宮村 浩子; 呉田 昌俊; 瀬川 麻里子; 久保 純*; 斎藤 隆文*; 鈴木 喜雄; 武宮 博

Proceedings of 11th Asian Symposium on Visualization (ASV-11) (CD-ROM), 4 Pages, 2011/06



Progress of ultra-high-speed image sensors with in-situ CCD storage

江藤 剛治*; Dao, V. T. S.*; Nguyen, H. D.*; Fife, K.*; 呉田 昌俊; 瀬川 麻里子; 新井 正敏; 篠原 武尚

Proceedings of 2011 International Image Sensor Workshop (IISW), 4 Pages, 2011/06



Feasibility study on visualization of transient phenomena using high resolution on-line neutron imaging system at J-PARC

瀬川 麻里子; 甲斐 哲也; 大井 元貴; 高峰 潤; 呉田 昌俊

Proceedings of 2011 IEEE Nuclear Science Symposium and Medical Imaging Conference (2011 NSS/MIC) (DVD-ROM), p.385 - 392, 2011/00

In the present study, we aimed to develop a neutron imaging system which allows us to visualize transient phenomena with high spatial resolution and real-time. Therefore, a camera (CMOS, 48 frame/sec) system which could obtain one TOF image resolved into narrow energy ranges with an each single pulsed neutron consecutively in the energy region from 0.01 to a few keV was constructed. Qualities of the images obtained with the system, such as spatial resolution, neutron energy selectivity of the system, and capability for visualization of transient phenomena, were examined experimentally. The results figured out that the spatial resolution defined by modulation transfer function was 1.8 at En $$sim$$ 0.01 eV. And the energy selectivity was confirmed by the scanning of the sample made by Au, which had a large resonance at En = 4.9 eV. Finally, the system could visualize the transient phenomena to fall the Fe powder on a sandglass. The experiments showed that the system can visualize the real-time neutron energy resolved images with a good spatial resolution even at transient phenomena.


$$E1$$ and $$E2$$ cross sections of the $$^{12}$$C($$alpha$$,$$gamma$$)$$^{16}$$O reaction at $$E_{rm{eff}}$$ $$sim$$ 1.2 MeV using pulsed $$alpha$$ beams

牧井 宏之; 上田 仁*; 天満 康之*; 永井 泰樹*; 嶋 達志*; 藤本 臣哉*; 瀬川 麻里子; 三島 賢二*; 西山 潤*; 井頭 政之*

AIP Conference Proceedings 1269, p.283 - 288, 2010/10




A Facility for measurements of (n,$$gamma$$) cross-sections of a nucleus in the range 0.008 $$leq$$ $$E_{rm n}$$ $$<$$ 20 MeV

瀬川 麻里子; 藤 暢輔; 原田 秀郎; 北谷 文人; 小泉 光生; 初川 雄一; 深堀 智生; 松江 秀明; 大島 真澄; 谷村 嘉彦; et al.

Nuclear Instruments and Methods in Physics Research A, 618(1-3), p.153 - 159, 2010/06

 被引用回数:2 パーセンタイル:74.1(Instruments & Instrumentation)




宮村 浩子; 呉田 昌俊; 瀬川 麻里子; 久保 純*; 斎藤 隆文*; 鈴木 喜雄; 武宮 博

電気学会研究会資料,産業計測制御研究会(IIC-10-73), p.7 - 12, 2010/03


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