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論文

Neutron capture cross sections of curium isotopes measured with ANNRI at J-PARC

川瀬 頌一郎*; 木村 敦; 原田 秀郎; 岩本 信之; 岩本 修; 中村 詔司; 瀬川 麻里子; 藤 暢輔

Journal of Nuclear Science and Technology, 58(7), p.764 - 786, 2021/07

 被引用回数:0 パーセンタイル:0.01(Nuclear Science & Technology)

The neutron capture cross sections of $$^{244}$$Cm and $$^{246}$$Cm were measured for the neutron energy range of 1-1000 eV via the neutron time-of-flight method with ANNRI at MLF of the J-PARC. The world's most intense neutron pulses from the Japan Spallation Neutron Source enable the accurate measurement of neutron capture cross sections. Besides, single-bunched neutron pulses allow the analysis in a higher neutron energy region than the previous measurement at ANNRI. The resonance analyses were performed up to 1000 eV by using a resonance shape analysis code REFIT. The spectra of prompt gamma-rays from neutron capture reactions of $$^{244}$$Cm and $$^{246}$$Cm were also obtained, and 43 and 10 prompt gamma-ray peaks from $$^{244}$$Cm(n,$$gamma$$) and $$^{246}$$Cm(n,$$gamma$$) reactions were newly observed, respectively.

論文

Neutron beam filter system for fast neutron cross-section measurement at the ANNRI beamline of MLF/J-PARC

Rovira Leveroni, G.; 木村 敦; 中村 詔司; 遠藤 駿典; 岩本 修; 岩本 信之; 片渕 竜也*; 寺田 和司*; 児玉 有*; 中野 秀仁*; et al.

Nuclear Instruments and Methods in Physics Research A, 1003, p.165318_1 - 165318_10, 2021/07

 被引用回数:0 パーセンタイル:0.03(Instruments & Instrumentation)

A neutron filtering system has been introduced in the Accurate Neutron-Nucleus Reaction Measurement Instrument (ANNRI) beamline in the Material and Life Science (MLF) building of the Japan Proton Accelerator Research Complex (JPARC) in order to produce quasi-monoenergetic neutron beams. The filtered neutron spectrum by the filter assemblies was analyzed by means of capture and transmission measurements and also by Monte Carlo simulations using PHITS. The characteristics of the filtered neutron beam are discussed alongside its viability in future applications for neutron cross-section measurements in the fast neutron region.

論文

Improvement of HI concentration performance for hydrogen production iodine-sulfur process using crosslinked cation-exchange membrane

田中 伸幸; 澤田 真一*; 八巻 徹也*; 小平 岳秀*; 木村 壮宏*; 野村 幹弘*

Chemical Engineering Science, 237, p.116575_1 - 116575_11, 2021/06

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

熱化学水素製造法ISプロセスでは、HI-I$$_{2}$$-H$$_{2}$$O (HIx)溶液のHI濃縮のため、イオン交換膜を用いた電解電気透析法(EED)が適用されている。本報では、放射線グラフト膜に対して架橋構造を導入することで、HI濃縮性能の改良を試み、導電率($$sigma$$),輸率(t$$_{+}$$),水透過係数($$beta$$)の性能指標を用いて、実験的及び理論的に性能評価を行った。架橋導入により、H$$^{+}$$及び水の透過選択性が改善されることが示された。また、EEDの数理モデルに基づく理論解析から、架橋導入による影響はHI吸収量及びH$$^{+}$$拡散係数にはほとんど影響を与えず、I$$^{-}$$の拡散係数に影響することが明らかとなり、$$sigma$$, t$$_{+}$$に対しては、その結果が反映されることで、H$$^{+}$$の選択性が改善された。また、架橋の効果により、HI溶液の吸収に伴う膨潤が抑制され、その効果により、水の透過が抑制され、HI濃縮効果が高まることが示された。

論文

第32回NEA核データ評価国際協力ワーキングパーティ(WPEC)会合報告

岩本 修; 岩本 信之; 木村 敦; 多田 健一

核データニュース(インターネット), (127), p.1 - 10, 2020/10

経済協力開発機構原子力機関(OECD/NEA)で行われている核データ評価に関する国際協力の枠組みである核データ評価国際協力ワーキングパーティ(WPEC)の第32回年会とその下で活動しているサブグループの会合が、2020年5月11日から15日の日程でウェッブ形式で開催された。本年会では、各地域や各国の核データに関する測定及び評価の進捗とサブグループの活動状況が報告され、また、サブグループ会合ではそれぞれの活動に関する議論が行われた。これらの会合の概要について報告する。

論文

Evaluation of gamma-ray strength function based on measured gamma-ray pulse-height spectra in time-of-flight neutron capture experiments

岩本 信之; 中村 詔司; 木村 敦; 片渕 竜也*; Rovira, G.*; 原 かおる*; 岩本 修

EPJ Web of Conferences, 239, p.17016_1 - 17016_4, 2020/09

 被引用回数:0 パーセンタイル:0.19

Gamma-ray strength function (GSF) as well as nuclear level density is important ingredients to calculate neutron capture cross sections, since it gives energy-dependent transition strength of gamma-rays from a capture state and directly relates to spectrum of emitted gamma-rays. Therefore, the improvement of GSF is essential to enhance the reliability of neutron capture cross sections. The shape of GSF has been determined by experiments of neutron capture reactions, (p,p') reactions and nuclear resonance fluorescence. In addition, the use of the information of gamma-ray spectrum (i.e., pulse-height (PH) spectrum) measured by time-of-flight experiments is effective to evaluate the GSF. A lot of PH spectra have been measured by the Ge and NaI(Tl) detectors of the ANNRI installed at the Material and Life Science Experimental Facility in J-PARC. However, those spectra have not been actively used to extract the information of GSF so far. In the present study, we measured the PH spectrum of gold by using the NaI(Tl) detectors in ANNRI and used it for the evaluation of GSF. The gamma-ray spectrum for gold was calculated by a nuclear reaction model code CCONE. The obtained gamma-ray spectrum was applied to the Monte Carlo particle transport simulation code PHITS to derive PH spectrum comparable with the measured data. After this evaluation, we obtained GSF, reasonably explained the measured PH spectrum.

論文

HPRL; International cooperation to identify and monitor priority nuclear data needs for nuclear applications

Dupont, E.*; Bossant, M.*; Capote, R.*; Carlson, A. D.*; Danon, Y.*; Fleming, M.*; Ge, Z.*; 原田 秀郎; 岩本 修; 岩本 信之; et al.

EPJ Web of Conferences, 239, p.15005_1 - 15005_4, 2020/09

 被引用回数:0 パーセンタイル:0.19

The OECD-NEA High Priority Request List (HPRL) is a point of reference to guide and stimulate the improvement of nuclear data for nuclear energy and other nuclear applications. The HPRL is application-driven and the requests are submitted by nuclear data users or representatives of the user's communities. A panel of international experts reviews and monitors the requests in the framework of an Expert Group mandated by the NEA Nuclear Science Committee Working Party on International Nuclear Data Evaluation Cooperation (WPEC). After approval, individual requests are divided in two priority categories only, whereas a third category now includes groups of generic requests in a well-defined area (e.g., dosimetry, standard). The HPRL is hosted by the NEA in the form of a relational database publicly available on the web. This contribution provides an overview of HPRL entries, status and outlook. Examples of requests successfully completed will be given and new requests will be described with emphasis on updated nuclear data needs in the fields of nuclear energy, neutron standards, dosimetry, and medical applications.

論文

Fast neutron capture reaction data measurement of minor actinides for development of nuclear transmutation systems

片渕 竜也*; 岩本 修; 堀 順一*; 木村 敦; 岩本 信之; 中村 詔司; 芝原 雄司*; 寺田 和司*; Rovira, G.*; 松浦 翔太*

EPJ Web of Conferences, 239, p.01044_1 - 01044_4, 2020/09

 被引用回数:1 パーセンタイル:89.98

In 2017, a research project entitled "Study on accuracy improvement of fast-neutron capture reaction data of long-lived MAs for development of nuclear transmutation systems" started as a joint collaboration, including Tokyo Tech, Japan Atomic Energy Agency and Kyoto University. This project focuses on neutron capture reaction of MAs, especially $$^{237}$$Np, $$^{241}$$Am and $$^{243}$$Am, in the fast neutron energy region. The final goal of this project is to improve the neutron capture cross sections of $$^{237}$$Np, $$^{241}$$Am and $$^{243}$$Am employing a high-intensity neutron beam from a spallation source of the Japan Proton Accelerator Research Complex (J-PARC) that reduces uncertainties of measurement. In this contribution, the overview of the project and the current progress will be presented.

論文

Overvoltage reduction in membrane Bunsen reaction for hydrogen production by using a radiation-grafted cation exchange membrane and porous Au anode

澤田 真一*; 木村 壮宏*; 西嶋 陽之*; 小平 岳秀*; 田中 伸幸; 久保 真治; 今林 慎一郎*; 野村 幹弘*; 八巻 徹也*

International Journal of Hydrogen Energy, 45(27), p.13814 - 13820, 2020/05

 被引用回数:1 パーセンタイル:15.95(Chemistry, Physical)

熱化学水素製造法ISプロセスでは、カチオン交換膜を用いた膜ブンゼン反応が検討されている。しかし、従来のカチオン交換膜および電極材料では過電圧が高く、熱効率として採用できる段階ではなかった。本報では、高IECの放射線グラフト膜及び多孔質金電極を用いて、セルの過電圧を低下させることを目指した。放射線グラフト膜はプロトン透過に対する低い抵抗を示し、金電極はアノード極で生じるSO$$_{2}$$酸化反応を効率化した。この結果、膜ブンゼン反応で生じる過電圧が200mA/cm$$^{2}$$の条件で0.21Vまで削減された。本結果は、従来の商用カチオン交換膜及び非多孔質電極を用いた場合の1/3の値である。また、電流-電圧特性の解析結果から、放射線グラフト膜の方が金電極に比べて、より効果的に過電圧削減に貢献していることが明らかとなった。

論文

Neutron capture cross-section measurement and resolved resonance analysis of $$^{237}$$Np

Rovira, G.*; 片渕 竜也*; 登坂 健一*; 松浦 翔太*; 寺田 和司*; 岩本 修; 木村 敦; 中村 詔司; 岩本 信之; 瀬川 麻里子; et al.

Journal of Nuclear Science and Technology, 57(1), p.24 - 39, 2020/01

 被引用回数:4 パーセンタイル:84.6(Nuclear Science & Technology)

The neutron capture cross-section of $$^{237}$$Np has been measured in the neutron energy region of 10 meV to 500 eV. A neutron time-of-flight method was employed using the NaI(Tl) spectrometer in the ANNRI beam-line at the Japanese Proton Accelerator Re-search Complex (J-PARC). The experimental capture yield was derived using the pulse-height weighting technique and an energy dependent cross-section was obtained relative to the incident neutron spectrum derived from a $$^{10}$$B(n, $$alpha$$)$$^{7}$$Li reaction yield. The absolute cross-section was determined by normalizing the results to JENDL-4.0 cross-section data at the first resonance of $$^{237}$$Np. The thermal cross-section was measured to be 177.6 $$pm$$ 3.8 b. The resolved resonance region was analyzed with the REFIT code.

論文

Neutron capture reaction data measurement of minor actinides in fast neutron energy region for study on nuclear transmutation system

片渕 竜也*; 岩本 修; 堀 順一*; 岩本 信之; 木村 敦; 中村 詔司; 芝原 雄司*; 寺田 和司*

JAEA-Conf 2019-001, p.193 - 197, 2019/11

A research project entitled "Study on improvement of neutron capture reaction data accuracies of long-lived minor actinides in fast neutron energy region for development of nuclear transmutation systems" started in 2017. The project aims at improving accuracies of neutron capture cross section of long-lived minor actinides ($$^{237}$$Np, $$^{241}$$Am, $$^{243}$$Am) in the fast neutron energy region which are very important for development of nuclear transmutation systems. In order to improve the capture reaction data of MA, measurement using an intense pulsed neutron beam from a spallation neutron source of the Japan Proton Accelerator Research Complex (J-PARC) is planned. The neutron beam filter is designed to solve the so-called double bunch issue of a neutron beam in J-PARC. This allows for measuring neutron capture cross sections using the high-intensity neutron beam of J-PARC. The outline of the project and the current progress will be presented.

論文

第31回NEA核データ評価国際協力ワーキングパーティ(WPEC)会合報告

岩本 修; 岩本 信之; 木村 敦; 横山 賢治; 多田 健一

核データニュース(インターネット), (124), p.23 - 34, 2019/10

経済協力開発機構原子力機関(OECD/NEA)で行われている核データ評価に関する国際協力の枠組みである核データ評価国際協力ワーキングパーティ(WPEC)の第31回年会とその下で活動しているサブグループの会合が、2019年6月24$$sim$$28日の日程でパリ近郊のブローニュ=ビヤンクールにあるOECD/NEA本部において開かれた。本年会では、各地域や各国の核データに関する測定及び評価の進捗とサブグループの活動状況が報告され、サブグループ会合ではそれぞれの活動に関する議論が行われた。これらの会合の概要について報告する。

論文

Measurements of the $$^{243}$$Am neutron capture and total cross sections with ANNRI at J-PARC

木村 敦; 中村 詔司; 寺田 和司*; 中尾 太郎*; 水山 一仁*; 岩本 信之; 岩本 修; 原田 秀郎; 片渕 竜也*; 井頭 政之*; et al.

Journal of Nuclear Science and Technology, 56(6), p.479 - 492, 2019/06

 被引用回数:5 パーセンタイル:75.46(Nuclear Science & Technology)

Neutron total and capture cross sections of $$^{243}$$Am have been measured in Accurate Neutron Nucleus Reaction measurement Instrument at Materials and Life Science Experimental Facility of Japan Proton Accelerator Research Complex with a neutron TOF method. The neutron capture cross section in the energy region from 10 meV to 100 eV was determined using an array of Ge detectors. Three samples with different activities were used for measurements of the capture cross section. The neutron total cross section in the energy region from 4 meV to 100 eV was measured using Li-glass detectors. Derived cross-section value at neutron energy of 0.0253 eV is 87.7$$pm$$5.4 b for the capture cross section and 101$$pm$$11 b for the total cross section.

論文

Gamma-ray spectrum from thermal neutron capture on gadolinium-157

萩原 開人*; 矢野 孝臣*; Das, P. K.*; Lorenz, S.*; 王 岩*; 作田 誠*; 木村 敦; 中村 詔司; 岩本 信之; 原田 秀郎; et al.

Progress of Theoretical and Experimental Physics (Internet), 2019(2), p.023D01_1 - 023D01_26, 2019/02

 被引用回数:14 パーセンタイル:82.27(Physics, Multidisciplinary)

We have measured the $$gamma$$-ray energy spectrum from the thermal neutron capture, $$^{157}Gd(n,gamma)^{158}Gd$$, on an enriched $$^{157}$$Gd target ($$Gd_2O_3$$) in the energy range from 0.11 MeV up to about 8 MeV. The target was placed inside the germanium spectrometer of the ANNRI detector at J-PARC and exposed to a neutron beam from the Japan Spallation Neutron Source (JSNS). Radioactive sources ($$^{60}$$Co, $$^{137}$$Cs, and $$^{152}$$Eu) and the reaction $$^{35}Cl(n,gamma)$$ were used to determine the spectrometer's detection efficiency for $$gamma$$ rays at energies from 0.3 to 8.5 MeV. Using a Geant4-based Monte Carlo simulation of the detector and based on our data, we have developed a model to describe the $$gamma$$-ray spectrum from the thermal $$^{157}Gd(n,gamma)^{158}Gd$$ reaction. While we include the strength information of 15 prominent peaks above 5 MeV and associated peaks below 1.6 MeV from our data directly into the model, we rely on the theoretical inputs of nuclear level density and the photon strength function of $$^{158}$$Gd to describe the continuum $$gamma$$-ray spectrum from the $$^{157}Gd(n,gamma)^{158}Gd$$ reaction. The results of the comparison between the observed $$gamma$$-ray spectra from the reaction and the model are reported in detail.

論文

Measurements of neutron total and capture cross sections of $$^{241}$$Am with ANNRI at J-PARC

寺田 和司*; 木村 敦; 中尾 太郎*; 中村 詔司; 水山 一仁*; 岩本 信之; 岩本 修; 原田 秀郎; 片渕 竜也*; 井頭 政之*; et al.

Journal of Nuclear Science and Technology, 55(10), p.1198 - 1211, 2018/10

 被引用回数:10 パーセンタイル:87.34(Nuclear Science & Technology)

Neutron total and capture cross sections of $$^{241}$$Am have been measured with a new data acquisition system and a new neutron transmission measurement system installed in Accurate Neutron Nucleus Reaction measurement Instrument (ANNRI) at Materials and Life Science Experimental Facility (MLF) of Japan Proton Accelerator Research Complex (J-PARC). The neutron total cross sections of $$^{241}$$Am were determined by using a neutron time-of-flight method in the neutron energy region from 4 meV to 2 eV. The thermal total cross section of $$^{241}$$Am was derived with an uncertainty of 2.9%. A pulse-height weighting technique was applied to determine neutron capture yields of $$^{241}$$Am. The neutron capture cross sections were determined by the time-of-flight method in the neutron energy region from the thermal to 100 eV, and the thermal capture cross section was obtained with an uncertainty of 4.1%. The evaluation data of JENDL-4.0 and JEFF-3.2 were compared with the present results.

論文

第30回NEA核データ評価国際協力ワーキングパーティ(WPEC)会合報告

岩本 修; 岩本 信之; 木村 敦; 横山 賢治; 多田 健一

核データニュース(インターネット), (120), p.35 - 46, 2018/06

経済開発協力機構原子力機関(OECD/NEA)の第30回核データ評価国際ワーキングパーティ(WPEC)会合が、2018年5月14日から18日の日程でOECD本部で開催された。期間中に開催されたWPEC本会合、エキスパートグループ会合及びサブグループ会合について報告する。

論文

Application of modified REFIT code for J-PARC/MLF to evaluation of neutron capture cross section on $$^{155,157}$$Gd

水山 一仁; 岩本 信之; 岩本 修; 長谷美 宏幸*; 木野 幸一*; 木村 敦; 鬼柳 善明*

EPJ Web of Conferences, 146, p.11042_1 - 11042_4, 2017/09

 被引用回数:1 パーセンタイル:69.68

ガドリニウムは$$^{155,157}$$Gdが非常に大きな中性子捕獲断面積をもつため原子炉の中性子吸収材料として用いられる。しかしながら、$$^{157}$$GdのRPIデータとJENDL-4.0ではばらつきがあることが知られている。原子炉の臨界性は捕獲断面積に敏感であり、RPIのデータはICSBEPにあるガドミニウム溶液体系の臨界性を大きくしてしまうことがわかっている。近年、$$^{155,157}$$Gdの中性子捕獲断面積がJ-PARC/MLFでANNRIを用いた実験で飛行時間法によって測定された。J-PARCの中性子パルスはダブルバンチ構造を持っており、また、高精度な共鳴解析には中性子パルスの時間分解能関数も適切に考慮して行う必要がある。そこで、本研究では、中性子パルスのダブルバンチ構造やANNRI用の時間分解能関数を組み込んだ改良REFITを用いて中性子捕獲断面積の実験データをフィットし、共鳴パラメータを導出する。

論文

Research and development for accuracy improvement of neutron nuclear data on minor actinides

原田 秀郎; 岩本 修; 岩本 信之; 木村 敦; 寺田 和司; 中尾 太郎; 中村 詔司; 水山 一仁; 井頭 政之*; 片渕 竜也*; et al.

EPJ Web of Conferences, 146, p.11001_1 - 11001_6, 2017/09

 被引用回数:2 パーセンタイル:85.61

A nuclear data project entitled Research and development for Accuracy Improvement of neutron nuclear data on Minor ACtinides (AIMAC) is being performed in Japan. The objective of the project is to improve accuracy of neutron nuclear data for minor actinides and some fission products, which is required for developing innovative nuclear system transmuting these nuclei. Following research items have been conducted to achieve the objective: (1) Measurements of thermal neutron capture cross-sections by activation methods, (2) High-precision quantifications of shielded sample amounts used for TOF measurement, (3) Resonance parameter determinations at J-PARC/ANNRI and KURRI/LINAC, (4) Extension of capture cross sections to high energy neutrons at J-PARC/ANNRI, (5) High quality evaluation based on iterative communication with experimenters. The achievement of the project is presented.

論文

In-beam $$gamma$$-ray spectroscopy of $$^{35}$$Mg via knockout reactions at intermediate energies

籾山 悟至*; Doornenbal, P.*; Scheit, H.*; 武内 聡*; 新倉 潤*; 青井 考*; Li, K.*; 松下 昌史*; Steppenbeck, D.*; Wang, H.*; et al.

Physical Review C, 96(3), p.034328_1 - 034328_8, 2017/09

 被引用回数:5 パーセンタイル:51.78(Physics, Nuclear)

理化学研究所の不安定核実験施設RIBFにて、中性子過剰核$$^{35}$$Mgの励起状態を$$^{36}$$Mgおよび$$^{37}$$Alからのノックアウト反応によって生成し、そこからの脱励起$$gamma$$線を観測した。$$^{35}$$Mgは中性子数20魔法数が消滅するとされる「逆転の島」と呼ばれる領域に含まれると考えられており、また、奇核であることから、一粒子状態と集団的状態が結合した興味深い核構造が出現すると期待されている。この実験によって、206keV, 443keV, 616keV, 670keVの4本の$$gamma$$線を観測し、これらを全て基底状態へ脱励起する$$gamma$$線であると仮定して励起準位を構成した。この準位構造、ノックアウト反応の断面積、移行運動量分布を殻模型計算および反対称化分子動力学計算と比較した。二つの計算は、基底状態近傍の高い準位密度などいくつかの特徴的な核構造を再現することに成功し、$$^{35}$$Mgは「逆転の島」に含まれるという描像と無矛盾であることがわかった。

論文

Simultaneous measurement of neutron-induced fission and capture cross sections for $$^{241}$$Am at neutron energies below fission threshold

廣瀬 健太郎; 西尾 勝久; 牧井 宏之; 西中 一朗*; 太田 周也*; 永山 達郎*; 田村 信行*; 後藤 真一*; Andreyev, A.; Vermeulen, M. J.; et al.

Nuclear Instruments and Methods in Physics Research A, 856, p.133 - 138, 2017/06

 被引用回数:3 パーセンタイル:40.62(Instruments & Instrumentation)

Fission and capture reactions were simultaneously measured in the neutron-induced reactions of $$^{241}$$Am at J-PARC. Data were taken with the TOF method in $$E_n$$ = 0.1$$sim$$20 eV. The fission events were observed by detecting prompt fission neutrons using liquid organic scintillators. The capture reaction was measured by detecting $$gamma$$ rays from the compound nuclei using the same detectors, where the prompt fission neutrons and capture $$gamma$$ rays were separated by a pulse shape analysis. The cross sections were obtained by normalizing the relative yields at the first resonance to evaluations or other experimental data. The ratio of the fission to capture cross sections at each resonance is compared with those from an evaluated nuclear data library and other experimental data. Some differences were found between the present values and the library/literature values at several resonances.

論文

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:3 パーセンタイル:32.77(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.

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