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The $$^{59}$$Fe(n,$$gamma$$)$$^{60}$$Fe cross section from the surrogate ratio method and its effect on the $$^{60}$$Fe nucleosynthesis

Yan, S. Q.*; Li, X. Y.*; 西尾 勝久; Lugaro, M.*; Li, Z. H.*; 牧井 宏之; Pignatari, M.*; Wang, Y. B.*; Orlandi, R.; 廣瀬 健太郎; et al.

Astrophysical Journal, 919(2), p.84_1 - 84_7, 2021/10


The long-lived $$^{60}$$Fe (with a half-life of 2.62 Myr) is a crucial diagnostic of active nucleosynthesis in the Milky Way galaxy and in supernovae near the solar system. The neutron-capture reaction $$^{59}$$Fe(n,$$gamma$$)$$^{60}$$Fe on $$^{59}$$Fe (half-life=44.5 days) is the key reaction for the production of $$^{60}$$Fe in massive stars. This reaction cross section has been previously constrained by the Coulomb dissociation experiment, which offered partial constraint on the E1 $$gamma$$-ray strength function but a negligible constraint on the M1 and E2 components. In this work, for the first time, we use the surrogate ratio method to experimentally determine the $$^{59}$$Fe(n,$$gamma$$)$$^{60}$$Fe cross sections in which all the components are included. We derived a Maxwellian-averaged cross section of 27.5$$pm$$3.5 mb at $$kT$$ = 30 keV and 13.4$$pm$$1.7 mb at $$kT$$ = 90 keV, roughly 10%-20% higher than previous estimates. We analyzed the impact of our new reaction rates in nucleosynthesis models of massive stars and found that uncertainties in the production of $$^{60}$$Fe from the $$^{59}$$Fe(n,$$gamma$$)$$^{60}$$Fe rate are at most 25$$%$$. We conclude that stellar physics uncertainties now play a major role in the accurate evaluation of the stellar production of $$^{60}$$Fe.


Meteorological aspects of gamma-ray glows in winter thunderstorms

和田 有希*; 榎戸 輝揚*; 久保 守*; 中澤 知洋*; 篠田 太郎*; 米徳 大輔*; 澤野 達哉*; 湯浅 孝行*; 牛尾 知雄*; 佐藤 陽祐*; et al.

Geophysical Research Letters, 48(7), 11 Pages, 2021/04

 被引用回数:1 パーセンタイル:0(Geosciences, Multidisciplinary)



Oxygen enhancement ratios of cancer cells after exposure to intensity modulated X-ray fields; DNA damage and cell survival

松谷 悠佑; McMahon, S. J.*; Butterworth, K. T.*; 内城 信吾*; 奈良 一志*; 谷内 淑恵*; 嵯峨 涼*; 石川 正純*; 佐藤 達彦; 伊達 広行*; et al.

Physics in Medicine & Biology, 66(7), p.075014_1 - 075014_11, 2021/04

 被引用回数:0 パーセンタイル:0.01(Engineering, Biomedical)



Quasifree neutron knockout reaction reveals a small $$s$$-Orbital component in the Borromean nucleus $$^{17}$$B

Yang, Z. H.*; 久保田 悠樹*; Corsi, A.*; 吉田 数貴; Sun, X.-X.*; Li, J. G.*; 木村 真明*; Michel, N.*; 緒方 一介*; Yuan, C. X.*; et al.

Physical Review Letters, 126(8), p.082501_1 - 082501_8, 2021/02

 被引用回数:10 パーセンタイル:98.7(Physics, Multidisciplinary)

ボロミアン核であり中性子ハロー構造が期待される$$^{17}$$Bに対する($$p$$,$$pn$$)反応実験を行った。断面積の運動量分布を分析することで、$$1s_{1/2}$$$$0d_{5/2}$$軌道の分光学的因子を決定した。驚くべきことに、$$1s_{1/2}$$の分光学的因子は9(2)%と小さいことが明らかになった。この結果は、連続状態を含むdeformed relativistic Hartree-Bogoliubov理論によってよく説明された。本研究の結果によると、現在知られているハロー構造を持つとされる原子核の中で$$^{17}$$Bは$$s$$および$$p$$軌道の成分が最も小さく、$$s$$または$$p$$軌道成分が支配的であることが必ずしもハロー構造の前提条件ではない可能性を示唆している。


$$^{rm 208,207,206,nat}$$Pb(p,x)$$^{207}$$Bi and $$^{209}$$Bi(p,x)$$^{207}$$Bi excitation functions in the energy range of 0.04 - 2.6 GeV

Titarenko, Yu. E.*; Batyaev, V. F.*; Pavlov, K. V.*; Titarenko, A. Yu.*; Malinovskiy, S. V.*; Rogov, V. I.*; Zhivun, V. M.*; Kulevoy, T. V.*; Chauzova, M. V.*; Lushin, S. V.*; et al.

Nuclear Instruments and Methods in Physics Research A, 984, p.164635_1 - 164635_8, 2020/12

 被引用回数:0 パーセンタイル:0.02(Instruments & Instrumentation)

0.04から2.6GeVの陽子入射による$$^{rm 208,207,206,nat}$$Pb及び天然Biからの$$^{207}$$Bi生成断面積を直接$$gamma$$線スペクトロメトリの手法を用いて測定した。測定した結果は、モンテカルロ計算コードMCNP6.1, PHITS, Geant4及び核データライブラリTENDL-2019と比較した。その結果、一部の反応に対して計算と実験に不一致があることが分かり、その点について議論した。


A Model intercomparison of atmospheric $$^{137}$$Cs concentrations from the Fukushima Daiichi Nuclear Power Plant accident, phase III; Simulation with an identical source term and meteorological field at 1-km resolution

佐藤 陽祐*; 関山 剛*; Fang, S.*; 梶野 瑞王*; Qu$'e$rel, A.*; Qu$'e$lo, D.*; 近藤 裕昭*; 寺田 宏明; 門脇 正尚; 滝川 雅之*; et al.

Atmospheric Environment; X (Internet), 7, p.100086_1 - 100086_12, 2020/10



Dosimetric impact of a new computational voxel phantom series for the Japanese atomic bomb survivors; Methodological improvements and organ dose response functions

佐藤 達彦; 船本 幸代*; Paulbeck, C.*; Griffin, K.*; Lee, C.*; Cullings, H.*; Egbert, S. D.*; 遠藤 章; Hertel, N.*; Bolch, W. E.*

Radiation Research, 194(4), p.390 - 402, 2020/10

 被引用回数:2 パーセンタイル:0.01(Biology)



First online operation of TRIGA-TRAP

Grund, J.*; 浅井 雅人; Blaum, K.*; Block, M.*; Chenmarev, S.*; D$"u$llmann, Ch. E.*; Eberhardt, K.*; Lohse, S.*; 永目 諭一郎*; Nagy, Sz.*; et al.

Nuclear Instruments and Methods in Physics Research A, 972, p.164013_1 - 164013_8, 2020/08

 被引用回数:2 パーセンタイル:62.87(Instruments & Instrumentation)

ペニングトラップ型質量分析装置TRIGA-TRAPとTRIGA Mainz研究炉との結合に成功した。これにより、炉心近くに設置した$$^{235}$$U標的の中性子核分裂によって生成された短寿命核の高精度質量測定が可能となった。ターゲットチャンバから表面電離イオン源への短寿命核の効率的な輸送のためにエアロゾルガスジェットシステムを使用した。新規イオン光学系および改良型ビームモニタリングシステムを導入するとともに、実験装置のコミッショニングが終了した。表面イオン源の設計、実験装置の効率、および本装置を用いて得られた最初の結果を報告する。


Production of $$^{266}$$Bh in the $$^{248}$$Cm($$^{23}$$Na,5$$n$$)$$^{266}$$Bh reaction and its decay properties

羽場 宏光*; Fan, F.*; 加治 大哉*; 笠松 良崇*; 菊永 英寿*; 小森 有希子*; 近藤 成美*; 工藤 久昭*; 森本 幸司*; 森田 浩介*; et al.

Physical Review C, 102(2), p.024625_1 - 024625_12, 2020/08

 被引用回数:2 パーセンタイル:57.67(Physics, Nuclear)

The nuclide $$^{266}$$Bh was produced in the $$^{248}$$Cm($$^{23}$$Na,5n)$$^{266}$$Bh reaction at beam energies of 125.9, 130.6, and 135.3 MeV. Decay properties of $$^{266}$$Bh were investigated with a rotating wheel apparatus for $$alpha$$ and spontaneous fission (SF) spectrometry under low background conditions attained by a gas-jet transport system coupled to the RIKEN gas-filled recoil ion separator. The half-life of $$^{266}$$Bh was measured to be $$T_{rm 1/2}$$ = 10.0$$^{+2.6}_{-1.7}$$ s. The $$alpha$$-particle energies of $$^{266}$$Bh disperse widely in the range of 8.62 - 9.40 MeV. The maximum production cross section for the $$^{248}$$Cm($$^{23}$$Na,5n)$$^{266}$$Bh reaction was determined to be $$sigma$$ = 57 $$pm$$ 14 pb at 130.6 MeV.


Pulsed neutron imaging based crystallographic structure study of a Japanese sword made by Sukemasa in the Muromachi period

及川 健一; 鬼柳 善明*; 佐藤 博隆*; 大前 良磨*; Pham, A.*; 渡辺 賢一*; 松本 吉弘*; 篠原 武尚; 甲斐 哲也; Harjo, S.; et al.

Materials Research Proceedings, Vol.15, p.207 - 213, 2020/02

Japanese swords are very attractive not only as a work of art but also a metallurgical point of view. Since Japanese vintage swords became valuable, it is indispensable to establish non-destructive analysis method to identify some peculiar characteristics. Bragg edge imaging gives real-space distributions of bulk information in a crystalline material as well as neutron tomography. In this work, we investigated crystallographic information of a Japanese sword made by Sukemasa in Izumi province in the first quarter of the 16th century. The experiments have been performed at RADEN at J-PARC. The Sukemasa sword was measured with a counting-type 2D detector and with a CCD camera. We are now analyzing the measured 2D-transmission spectra using RITS code to obtain spatial distribution of the crystallite size, the texture variation, the d110 shift and its broadening. Complementary data analysis using white beam tomography is also on going. Detailed analysis results will be presented.


IRDFF-II; A New neutron metrology library

Trkov, A.*; Griffin, P. J.*; Simakov, S. P.*; Greenwood, L. R.*; Zolotarev, K. I.*; Capote, R.*; Aldama, D. L.*; Chechev, V.*; Destouches, C.*; Kahler, A. C.*; et al.

Nuclear Data Sheets, 163, p.1 - 108, 2020/01

 被引用回数:23 パーセンタイル:99.09(Physics, Nuclear)



PARaDIM; A PHITS-based Monte Carlo tool for internal dosimetry with tetrahedral mesh computational phantoms

Carter, L. M.*; Crawford, T. M.*; 佐藤 達彦; 古田 琢哉; Choi, C.*; Kim, C. H.*; Brown, J. L.*; Bolch, W. E.*; Zanzonico, P. B.*; Lewis, J. S.*

Journal of Nuclear Medicine, 60(12), p.1802 - 1811, 2019/12

 被引用回数:9 パーセンタイル:78.97(Radiology, Nuclear Medicine & Medical Imaging)



Development of TPC Trigger Hodoscope for J-PARC E42/E45 hadron experiment

Jung, W.*; Ahn, J. K.*; 長谷川 勝一; Hicks, K.*; Hwang, S.*; 市川 裕大; Kim, S.*; 佐甲 博之; 佐藤 進; 谷田 聖

JPS Conference Proceedings (Internet), 27, p.011007_1 - 011007_6, 2019/11

We have developed HypTPC consists of TPC and the trigger hodoscope for the J-PARC hadron experiments. The TPC Hodoscope has large scintillators of 80 $$times$$ 7 $$times$$ 1 cm$$^3$$ to cover the TPC. Especially, we have developed a readout circuit for multiple MPPCs to detect photons generated over a large area of the scintillator. A general methods of applying voltage to multiple MPPCs are parallel and series connections. In the case of parallel connections, a signal has a long tail due to the large sensor capacitance. MEG collaboration used four MPPC segments as a serial connection. However, in the case of a series connection, the requiring bias voltage is very high, and the gain is low. To avoid this problem, we have developed a new individual biasing method with a summing amplifier for stable multiple MPPC readouts. We also made prototype detectors and performed a cosmic-ray test. Brief descriptions of our prototypes and preliminary results of the cosmic-ray test are presented in this article.


First $$gamma$$-ray spectroscopy of an $$sd$$-shell hypernucleus, $$^{19}_{Lambda}$$F

Yang, S. B.*; 長谷川 勝一; 早川 修平*; 細見 健二; 市川 裕大; 今井 憲一; 佐甲 博之; 佐藤 進; 田村 裕和*; 谷田 聖; et al.

JPS Conference Proceedings (Internet), 26, p.023015_1 - 023015_5, 2019/11

We performed a gamma-ray spectroscopy of $$({}_{Lambda}^{19}{rm F})$$ at J-PARC Hadron Experimental Facility in 2015. It is the first measurement of $$gamma$$ rays emitted from $$sd$$-shell hypernuclei. In this experiment, we determined the energy spacing between the ground state spin doublet, $$3/2^+$$ and $$1/2^+$$ states, as 316 keV. The excitation energies of $$5/2^+$$ and $$1/2^+$$ states are also determined to be 895 and 1266 keV, respectively. The energy spacing is found to be well reproduced by shell-model calculations which describe $$s$$- and $$p$$-shell $$Lambda$$ hypernuclei well. The results show that the present theories of the $$Lambda N$$ interaction describe not only the light hypernuclei but also a heavier hypernucleus.


High-rate performance of a time projection chamber for an H-dibaryon search experiment at J-PARC

Kim, S. H.*; 市川 裕大; 佐甲 博之; 長谷川 勝一; 早川 修平*; 七村 拓野*; 佐藤 進; 谷田 聖; 吉田 純也; 他11名*

Nuclear Instruments and Methods in Physics Research A, 940, p.359 - 370, 2019/10

 被引用回数:2 パーセンタイル:42.44(Instruments & Instrumentation)

We have developed a gas electron multiplier (GEM)-based time projection chamber (TPC) for the H-dibaryon search experiment at J-PARC. High-rate $$K^-$$ beam particles enter a TPC gas volume of approximately 0.2 m$$^3$$, in a direction perpendicular to the electric field. A long-rectangular hollow section is located inside the TPC volume to accommodate a diamond target. We commissioned the TPC using 230 MeV protons with beam rates of up to 1 MHz. The TPC data acquisition system collected 5768 pad signals in full readout mode, with almost 100% efficiency, at a preset trigger rate of 230 Hz. We operated the TPC in an Ar/CH$$_4$$ gas mixture (90/10) without a magnetic field. The spatial resolutions on the pad plane are measured to be 400-700 $$mu$$m, which correspond to 230-300 $$mu$$m in a magnetic field of 1 T. We confirmed high tracking capability at beam rates of up to 1 MHz.


Search for $$alpha$$ decay of $$^{104}$$Te with a novel recoil-decay scintillation detector

Xiao, Y.*; Go, S.*; Grzywacz, R.*; Orlandi, R.; Andreyev, A. N.; 浅井 雅人; Bentley, M. A.*; de Angelis, G.*; Gross, C. J.*; Hausladen, P.*; et al.

Physical Review C, 100(3), p.034315_1 - 034315_8, 2019/09

 被引用回数:10 パーセンタイル:88.51(Physics, Nuclear)

A search for super-allowed $$alpha$$ decay of N=Z nuclei $$^{104}$$Te and $$^{108}$$Xe was carried out using a novel recoil-decay scintillator detector at the tandem accelerator facility at Japan Atomic Energy Agency. Inorganic crystal scintillation material of YAP:Ce (Yttrium Aluminium Perovskite) coupled to position-sensitive photo-multiplier tube (PSPMT) was implemented for the first time in a radioactive decay experiment. Residues from the fusion-evaporation reaction $$^{58}$$Ni+$$^{54}$$Fe$$rightarrow$$ $$^{112}$$Xe$$^*$$ were separated by the JAEA Recoil Mass Separator (RMS) and implanted into the YAP:Ce crystal. $$alpha$$ decays of neutron-deficient tellurium isotopes were identified and proton-emission of $$^{109}$$I was observed. No conclusive evidence was found for the decay chain $$^{108}$$Xe$$rightarrow$$$$^{104}$$Te$$rightarrow$$ $$^{100}$$Sn within 3 days experiment. The cross section limit of 130 pb was obtained for production of two events of $$^{108}$$Xe, about an order of magnitude below the expectation based on earlier cross section measurements and HIVAP calculations.


Dosimetric impact of a new computational voxel phantom series for the Japanese atomic bomb survivors; Pregnant females

Paulbeck, C.*; Griffin, K.*; Lee, C.*; Cullings, H.*; Egbert, S. D.*; 船本 幸代*; 佐藤 達彦; 遠藤 章; Hertel, N.*; Bolch, W. E.*

Radiation Research, 192(5), p.538 - 561, 2019/08

 被引用回数:4 パーセンタイル:42.47(Biology)

妊婦及び胎児の原爆生存者に対する被ばく線量評価は、放射線影響の疫学研究の上で極めて重要となる。従来は、女性の子宮壁に対する線量を妊婦及び胎児の被ばく線量と仮定していたが、本研究では、最新の計算科学記述を用いて受胎8, 15, 25, 38週齢の胎児及び妊婦に対する詳細人体モデルを構築し、その被ばく線量を精度よく計算した。その結果、従来手法では、光子及び中性子前方照射に対して最大で12-16%及び44-54%被ばく線量を過大評価していたことが分かった。これらの結果は、今後、妊婦及び胎児に対する放射線感受性の疫学調査を実施する上で、極めて重要となる。


Enhancement of element production by incomplete fusion reaction with weakly bound deuteron

Wang, H.*; 大津 秀暁*; 千賀 信幸*; 川瀬 頌一郎*; 武内 聡*; 炭竃 聡之*; 小山 俊平*; 櫻井 博儀*; 渡辺 幸信*; 中山 梓介; et al.

Communications Physics (Internet), 2(1), p.78_1 - 78_6, 2019/07

 被引用回数:5 パーセンタイル:62.37(Physics, Multidisciplinary)



Intensity modulated radiation fields induce protective effects and reduce importance of dose-rate effects

松谷 悠佑; McMahon, S. J.*; Ghita, M.*; 吉井 勇治*; 佐藤 達彦; 伊達 広行*; Prise, K. M.*

Scientific Reports (Internet), 9(1), p.9483_1 - 9483_12, 2019/07

 被引用回数:6 パーセンタイル:65.54(Multidisciplinary Sciences)

放射線治療において、強度変調放射線場と複雑な線量伝達を使用して腫瘍へ高線量を処方する。しかしながら、それらを組み合わせた照射中の細胞応答は未だ明らかになっていない。そこで、強度変調放射線場が放射線感受性と照射中の回復に与える影響を解析した。先ず、培養細胞を含む培養フラスコの50%(半照射野)もしくは100%(全照射野)の面積に照射を行った。また、線量率と細胞間シグナルの両効果を考慮した細胞死を表現しうるモデルを構築した。その結果、(i)同吸収線量被ばく時の全照射野被ばくと比較し、半照射野被ばく時の照射野内細胞は高い生存率を示し、(ii)半照射野下におけるヒト正常皮膚線維芽細胞の亜致死損傷 回復の重要度が低減することが分かった。さらに、(iii)半照射野時の生存率の増加はレスキュー効果(修復の増加)ではなく防御効果(初期DNA損傷生成率の低減)に起因する知見を得た。これらの知見は、不均一被ばく後の照射細胞と非照射細胞に対する放射線感受性の新たな理解に貢献するものである。


Dosimetric impact of a new computational voxel phantom series for the Japanese atomic bomb survivors; Children and adults

Griffin, K.*; Paulbeck, C.*; Bolch, W.*; Cullings, H.*; Egbert, S. D.*; 船本 幸代*; 佐藤 達彦; 遠藤 章; Hertel, N.*; Lee, C.*

Radiation Research, 191(4), p.369 - 379, 2019/04

 被引用回数:9 パーセンタイル:75.27(Biology)


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