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Spin and parity determination of the 3.004-MeV level in $$^{27}$$Al; Its low-lying multiplet structure

静間 俊行*; Omer, M.; 羽島 良一*; 清水 則孝*; 宇都野 穣

Physical Review C, 100(1), p.014307_1 - 014307_6, 2019/07

Nuclear resonance fluorescence (NRF) is a promising technique for the nondestructive assay (NDA) of nuclear materials. One of the features of the NRF is the angular distribution of the emitted photons in response to a linearly polarized incident beam. Here we irradiate the calibration standard of $$^{27}$$Al to linearly polarized beam. The spin and parity of the 3.004-MeV level in $$^{27}$$Al have been determined by measuring the angular correlation function of radiation emitted from levels populated by resonant absorption of polarized photons. The nuclear resonance fluorescence experiments were carried out at the High Intensity $$gamma$$-ray Source (HI$$gamma$$S) facility at Duke University using quasi-monoenergetic linearly polarized photon beams. The spin and parity of levels in $$^{27}$$Al were deduced from a comparison of the measured angular distribution ratios and azimuthal intensity asymmetries with theoretical predictions. The observed resonance properties were compared with shell model calculations using the universal sd interaction. The Monte Carlo shell model calculations were also performed to investigate low-energy structure of $$^{27}$$Al. This work was supported by the subsidiary for promotion of strengthening nuclear security or the like of the Ministry of Education, Culture, Sports, Science, and Technology (MEXT), Japan.


Dipole strength distribution in $$^{206}$$Pb for the evaluation of the neutron capture cross section of $$^{205}$$Pb

静間 俊行; 岩本 信之; 牧永 あや乃*; Massarczyk, R.*; Schwengner, R.*; Beyer, R.*; Bemmerer, D.*; Dietz, M.*; Junghans, A.*; K$"o$gler, T.*; et al.

Physical Review C, 98(6), p.064317_1 - 064317_12, 2018/12

 パーセンタイル:100(Physics, Nuclear)



Evaluation of neutron capture cross section on $$^{205}$$Pb with photonuclear data

岩本 信之; 静間 俊行*

EPJ Web of Conferences (Internet), 178, p.06004_1 - 06004_3, 2018/05

Transmutation and reduction of high level radioactive wastes (e.g. minor actinides) produced in nuclear reactors are expected by an accelerator driven system (ADS). Japan Atomic Energy Agency proposed that Pb and Bi are used as a spallation target and coolant. The neutronics design was performed without including $$^{205}$$Pb, which is a long-lived radioactive nuclide with half-life of 1.7$$times$$10$$^{7}$$ years and thus has long-lasting radiotoxicity. $$^{205}$$Pb is produced by the neutron capture reaction on $$^{204}$$Pb. In order to evaluate the accumulated amount of $$^{205}$$Pb, the neutron capture cross section of $$^{205}$$Pb is needed. However, it has not been measured in the keV to MeV neutron energy region. In the present work the calculations of cross sections were performed by the nuclear reaction calculation code, CCONE. Measured photonuclear data of ($$gamma$$,$$gamma$$) reaction and photoneutron cross sections were used to evaluate photon strength function of $$^{206}$$Pb. The ($$gamma$$,$$gamma$$) reaction data used were newly obtained by an experiment at HZDR. The fixed photon strength function was applied to calculate the neutron capture cross sections of $$^{205}$$Pb. The resulting cross section is smaller than the data of $$^{204}$$Pb in the relevant energy region.


Low-lying dipole strength in $$^{52}$$Cr

静間 俊行*; 早川 岳人*; 大東 出*; 大垣 英明*; 宮本 修治*; 湊 太志

Physical Review C, 96(4), p.044316_1 - 044316_10, 2017/10

 被引用回数:2 パーセンタイル:52.65(Physics, Nuclear)

準単色線形偏向光子ビームを用いた核共鳴蛍光散乱実験によって、$$^{52}$$Crの低エネルギー双極子強度を測定した。励起状態のパリティは、入射光子ビームの偏極面における共鳴散乱$$gamma$$線の非対称性により決定した。励起エネルギー7.5MeVから12.1MeVまでの磁気双極子(M1)強度の総和は$$sum B(M1)uparrow=5.64(34) mu_N^2$$、電気双極子(E1)強度は$$sum B(E1)uparrow=73.7(23) times 10^{-3} e^2$$ fm$$^2$$という結果が得られた。観測されたM1とE1強度はSkyrme力を用いた乱雑位相近似法計算と比較を行い、双極子強度分布に対する2粒子2空孔状態とテンソル力の影響を調べた。この結果、2粒子2空孔状態とテンソル力の効果がともに、実験データの遷移強度の和を説明するために必要であることが分かった。


Effects of $$gamma$$-ray polarization in NRF-based nondestructive assay of nuclear materials

Omer, M.; 羽島 良一*; 静間 俊行*; 小泉 光生

Proceedings of INMM 58th Annual Meeting (Internet), 7 Pages, 2017/07



Measurement of the isomer production ratio for the $$^{112}$$Cd($$n,gamma$$)$$^{113}$$Cd reaction using neutron beams at J-PARC

早川 岳人*; 藤 暢輔; Huang, M.; 静間 俊行*; 木村 敦; 中村 詔司; 原田 秀郎; 岩本 信之; 千葉 敏*; 梶野 敏貴*

Physical Review C, 94(5), p.055803_1 - 055803_6, 2016/11

 被引用回数:1 パーセンタイル:79.57(Physics, Nuclear)

The astrophysical origin of a rare isotope $$^{115}$$Sn has remained still an open question. An isomer ($$T_{1/2}$$=14.1 y) in $$^{113}$$Cd is an s-process branching point from which a nucleosynthesis flow reaches to $$^{115}$$Sn. The $$s$$-process abundance of $$^{115}$$Sn depends on the isomer production ratio in the $$^{112}$$Cd($$n,gamma$$)$$^{113}$$Cd reaction. However, the ratio has not been measured in an energy region higher than the thermal energy. We have measured $$gamma$$ rays following neutron capture reactions on $$^{112}$$Cd using two cluster HPGe detectors in conjunction with a time-of-flight method at J-PARC. We have obtained the result that the relative $$gamma$$-ray intensity ratio of the isomer is almost constant in an energy region of up to 5 keV. This result suggests that the $$s$$-process contribution to the solar abundance of $$^{115}$$Sn is negligibly small. We have found that the ratio of a resonance at 737 eV shows about 1.5 times higher than other ratios. This enhancement can be explained by a $$p$$-wave neutron capture. This result suggests measurements of decay $$gamma$$ rays to isomers are effective to assign the spin and parity for neutron capture resonances.


Simulation of the elastic scattering contributions to the NRF-based nondestructive assay of nuclear materials

Omer, M.; 羽島 良一*; Angell, C.*; 静間 俊行*; 早川 岳人*; 瀬谷 道夫; 小泉 光生

Proceedings of INMM 57th Annual Meeting (Internet), 9 Pages, 2016/07




羽島 良一; 沢村 勝; 永井 良治; 西森 信行; 早川 岳人; 静間 俊行; Angell, C.

Proceedings of 12th Annual Meeting of Particle Accelerator Society of Japan (インターネット), p.79 - 83, 2015/09




永井 良治; 羽島 良一; 静間 俊行; 森 道昭; 赤木 智哉*; 小菅 淳*; 本田 洋介*; 荒木 栄*; 照沼 信浩*; 浦川 順治*

Proceedings of 12th Annual Meeting of Particle Accelerator Society of Japan (インターネット), p.1328 - 1330, 2015/09

コンパクトERL(cERL)においてエネルギー回収型リニアックを基盤とするレーザーコンプトン散乱(LCS)光源のために必要な加速器およびレーザーについての技術開発を行った。ERL-LCS光源のような高強度,エネルギー可変,単色光源は非破壊核種分析に必要な光源である。ERL-LCS光源による光子生成実証のために、cERLの回収ループにレーザーエンハンスメント共振器を設置した。電子ビームエネルギー,レーザー波長,衝突角はそれぞれ、20MeV, 1064nm, 18$$^{circ}$$である。LCS光子の最大エネルギーは約7keVである。感度領域17mm$$^{2}$$のシリコンドリフト検出器を衝突点から16.6mの位置でのLCS光子の観測に用いた。その計測の結果、検出器での強度、中心エネルギー、エネルギー広がりはそれぞれ、1200/s, 6.91keV, 81eVであった。


Demonstrating the integral resonance transmission method; Conceptual and experimental studies

Angell, C.; 早川 岳人; 静間 俊行; 羽島 良一; Quiter, B. J.*; Ludewigt, B. L.*; Karwowski, H. J.*; Rich, G.*; Silano, J.*

Proceedings of INMM 56th Annual Meeting (Internet), 9 Pages, 2015/07

Nuclear resonance fluorescence (NRF) is a promising technique for assaying $$^{239}$$Pu in spent nuclear fuel and for SNM detection applications because of its isotope-specific nature and potential for high sensitivity. To fully utilize the next generation of high-flux $$gamma$$-ray sources for NRF applications we developed the integral resonance transmission (IRT) method which integratesover all resonances within the energy width of a quasi-monoenergetic $$gamma$$-ray beam allowing the full utilization of the transmission signature. To realize the IRT technique both conceptual studies, exploring the consequences of the loss of resolution, and experimental studies, demonstrating several aspects of the IRT method, were undertaken. The conceptual studies included the development of a performance metric allowing comparison between using the IRT technique and single resonances, a study of the magnitude of resonance overlap, and beam simulations examining performance as a function of beam width. The experimental studies were done at the HI$$gamma$$S facility at Duke University, and included an experiment constraining resonance overlap in a NRF transmission measurement through a TMI-2 type canister, demonstration of the IRT technique by a NRF measurement on $$^{181}$$Ta, and the world's first transmission NRF measurement on $$^{239}$$Pu. In this talk, we will overview each component of the conceptual and experimental studies for the IRT method.


Superdeformation in $$^{35}$$S

郷 慎太郎*; 井手口 栄治*; 横山 輪*; 小林 幹*; 木佐森 慶一*; 高木 基伸*; 宮 裕之*; 大田 晋輔*; 道正 新一郎*; 下浦 享*; et al.

JPS Conference Proceedings (Internet), 6, p.030005_1 - 030005_4, 2015/06

The high-spin states in $$^{35}$$S were investigated at Tandem-ALTO facility in Institut de Physique Nucl$'e$aire d'Orsay The $$^{26}$$Mg($$^{18}$$O, 2$$alpha$$1n)$$^{35}$$S fusion evaporation reaction was used to populate high-spin states in $$^{35}$$S. The germanium $$gamma$$-ray detector array ORGAM was employed to measure $$gamma$$ rays from high-spin states and charged particles evaporated from the compound nuclei were detected by a segmented silicon detector, Si-Ball. A level scheme for $$^{35}$$S was deduced based on the gamma-gamma-coincidence analysis and $$gamma$$-ray angular correlation analysis. The half-life of the transition in the superdeformed band was estimated by measuring the residual Doppler shift. The deduced half-life shows the large collectivity of the band.


Reaction-yield dependence of the ($$gamma$$, $$gamma$$') reaction of $$^{238}$$U on the target thickness

Negm, H.*; 大垣 英明*; 大東 出*; 早川 岳人; Zen, H.*; 紀井 俊輝*; 増田 開*; 堀 利匡*; 羽島 良一; 静間 俊行; et al.

Journal of Nuclear Science and Technology, 52(6), p.811 - 820, 2015/06

 被引用回数:1 パーセンタイル:81.41(Nuclear Science & Technology)



Demonstration of high-flux photon generation from an ERL-based laser Compton photon source

永井 良治; 羽島 良一; 森 道昭; 静間 俊行; 赤木 智哉*; 荒木 栄*; 本田 洋介*; 小菅 淳*; 照沼 信浩*; 浦川 順治*

Proceedings of 6th International Particle Accelerator Conference (IPAC '15) (Internet), p.1607 - 1609, 2015/06

コンパクトERL(cERL)においてエネルギー回収型リニアックを基盤とするレーザーコンプトン散乱(LCS)光源のために必要な加速器およびレーザーについての技術開発を行った。ERL-LCS光源のような高強度、エネルギー可変、単色光源は非破壊核種分析に必要な光源である。ERL-LCS光源による光子生成実証のために、cERL回収ループにレーザーエンハンスメント共振器を設置した。電子ビームエネルギー、レーザー波長、衝突角はそれぞれ、20MeV, 1064nm, 18deg.である。LCS光子の最大エネルギーは約7keVである。感度領域17mm$$^{2}$$のシリコンドリフト検出器を衝突点から16.6mの位置でのLCS光子の観測に用いた。その計測の結果、検出器での強度、中心エネルギー、エネルギー広がりはそれぞれ、1200/s, 6.91keV, 81eVであった。


Diffraction of $$gamma$$-rays with energies of 1.17 and 1.33 MeV by a flat Si crystal

松葉 俊哉*; 早川 岳人; 静間 俊行; 西森 信行; 永井 良治; 沢村 勝; Angell, C.; 藤原 守; 羽島 良一

Japanese Journal of Applied Physics, 54(5), p.052203_1 - 052203_5, 2015/05

 被引用回数:3 パーセンタイル:74.64(Physics, Applied)

Diffraction of $$gamma$$-rays by a flat Si crystal has been demonstrated using a high flux $$^{60}$$Co source with an intensity of 2.3 TBq. The diffraction intensities of the $$gamma$$-rays with energies of 1.17 and 1.33 MeV have been measured as a function of the rotation angle of the crystal. Three peaks corresponding to the Si(440) and Si(220) diffractions for 1.17 MeV and the Si(440) diffraction for 1.33 MeV have been measured. The heights and shapes of these three peaks are well reproduced by taking into account Bragg's law and the experimental geometry.


Demonstration of a transmission nuclear resonance fluorescence measurement for a realistic radioactive waste canister scenario

Angell, C.; 羽島 良一; 早川 岳人; 静間 俊行; Karwowski, H.*; Silano, J.*

Nuclear Instruments and Methods in Physics Research B, 347, p.11 - 19, 2015/03

 被引用回数:5 パーセンタイル:34.97(Instruments & Instrumentation)

Transmission nuclear resonance fluorescence (NRF) is a promising method for precision non-destructive assay (NDA) of fissile isotopes including $$^{239}$$Pu in spent fuel while inside a storage canister. The assay, however, could be confounded by the presence of overlapping resonances from competing isotopes in the canister. A measurement is needed to demonstrate that transmission NRF is unaffected by the shielding material. To this end, we carried out a transmission NRF measurement using a mono-energetic $$gamma$$-ray beam on a proxy target (Al) and absorbing material simulating a realistic spent fuel storage canister. Similar amounts of material as would be found in a possible spent fuel storage canister were placed upstream: concrete, stainless steel (SS 304), lead (as a proxy for U), and water. An Al absorption target was also used as a reference. These measurements demonstrated that the canister material should not significantly influence the non-destructive assay.



羽島 良一; 静間 俊行; 永井 良治; 森 道昭; 早川 岳人; Angell, C.; 瀬谷 道夫

核物質管理学会(INMM)日本支部第35回年次大会論文集(インターネット), 7 Pages, 2015/01

日本原子力研究開発機構は、レーザー・コンプトン散乱(LCS)で生成する大強度単色$$gamma$$線(LCS $$gamma$$線)と原子核共鳴蛍光散乱(NRF)による核種の非破壊測定を提案し、これに必要な基盤技術開発を行っている。平成26年度は、4年間の技術開発プログラムの最終年度としてLCS $$gamma$$線の発生実証試験(実証試験)をコンパクトERL(ERL試験加速器)にて実施する予定であり、高エネルギー加速器研究機構の協力のもと、実証試験の準備を進めている。コンパクトERLは2014年3月12日に完成検査に合格し、同6月20日までの運転では実証試験に向けた電子ビーム調整などを行った。2014年7月から12月までの加速器の停止期間中にLCS用レーザー、電子・レーザー衝突用真空容器、ビームライン、LCS $$gamma$$線測定装置などの設置を行い、2015年1月以降に実証試験を開始する。本発表では、これら、(LCS $$gamma$$線の発生)実証試験に向けた準備状況を報告する。


Improving the assay of $$^{239}$$Pu in spent and melted fuel using the nuclear resonance fluorescence integral resonance transmission method

Angell, C.; 早川 岳人; 静間 俊行; 羽島 良一; Quiter, B. J.*; Ludewigt, B. L.*; Karwowski, H.*; Rich, G.*

Nuclear Physics and $$gamma$$-ray sources for Nuclear Security and Nonproliferation, p.133 - 141, 2014/12

Non-destructive assay (NDA) of $$^{239}$$Pu in spent nuclear fuel is possible using the isotope-specific nuclear resonance fluorescence (NRF) integral resonance transmission (IRT) method. The IRT method measures the absorption of photons from a quasi-monoenergetic $$gamma$$-ray beam due to all resonances in the energy width of the beam. According to calculations the IRT method could greatly improve assay times for $$^{239}$$Pu in nuclear fuel. To demonstrate and verify the IRT method, we first measured the IRT signature in $$^{181}$$Ta, and subsequently made IRT measurements in $$^{239}$$Pu. These measurements were done using the quasi-monoenergetic beam at the High Intensity $$gamma$$-ray Source (HI$$gamma$$S) in Durham, NC, USA. The IRT signature was observed as a decrease in scattering strength when the same isotope material was placed in the beam line upstream of the scattering target. The results confirm the validity of the IRT method in both $$^{181}$$Ta and $$^{239}$$Pu.


Validating resonance properties using nuclear resonance fluorescence

Angell, C.; 羽島 良一; 早川 岳人; 静間 俊行; Karwowski, H.*; Silano, J.*

Physical Review C, 90(5), p.054315_1 - 054315_6, 2014/11


 被引用回数:3 パーセンタイル:63.98(Physics, Nuclear)

Measurement of a resonance's integrated cross section using nuclear resonance fluorescence can be a valuable tool for verifying the properties of the resonance because of the clear and unambiguous physical connection to the spin, lifetime, and ground state branching ratio of the level. We demonstrate this idea by measuring the integrated cross section of the 3.004 MeV level in $$^{27}$$Al to 4% using the mono-energetic $$gamma$$-ray beam at the High Intensity $$gamma$$-ray Source. That level was the subject of much debate experimentally in the 1960's, especially its spin, and even now only has a current tentative spin assignment of $$J=(9/2)$$. The consistency check between this integrated cross section and the known properties of the level indicate that one (or more)of the literature properties is incorrect. Based on the range of extent of each property, a re-assignment of spin to atentative $$J=(7/2)$$ may be warranted, but this would need to be confirmed with other measurements. This result demonstrates the utility of NRF as a way to verify the properties of states in the literature before undertaking more extensive measurements.



永井 良治; 羽島 良一; 森 道昭; 静間 俊行; 赤木 智哉*; 小菅 淳*; 本田 洋介*; 浦川 順治*

Proceedings of 11th Annual Meeting of Particle Accelerator Society of Japan (インターネット), p.1328 - 1331, 2014/10




永井 良治; 羽島 良一; 森 道昭; 静間 俊行; 赤木 智哉*; 小菅 淳*; 本田 洋介*; 浦川 順治*

Proceedings of 11th Annual Meeting of Particle Accelerator Society of Japan (インターネット), p.839 - 842, 2014/10


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