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2024年度核データ研究会のお知らせ
日本原子力学会核データ部会、京都大学複合原子力科学研究所主催、日本原子力学会「シグマ」調査専門委員会、日本原子力研究開発機構 原子力基礎工学研究センター、高エネルギー加速器研究機構共催の「2024年度核データ研究会」を下記のとおり開催いたします。皆様の多数のご参加をお願い申し上げます。
プログラム案(http://www.aesj.or.jp/~ndd/symposium/2024program.pdf)
研究会セッションテーマは以下の通りです。
また、1日目(11月14日)の午前中(10:30-12:00)には、京都大学複合原子力科学研究所の施設見学(研究用原子炉KUR、サイクロトロン)も予定しています。見学を申し込まれる方はRegistration formにて申し込みをしてください。先着順にて定員20名に限らせていただきます。
なお、本研究会は京都大学複合原子力科学研究所の専門研究会として実施するため、参加者に対する旅費の補助があります。原則として、発表者及び学生を優先させていただきます。旅費補助の希望がありましたらその旨参加登録の際にご記入ください。ただし、財源に限りがありますので、配分につきましては実行委員会にご一任ください。
2024年度核データ研究会実行委員会委員長
堀 順一
締切日
＊研究会後、口頭及びポスター発表者に対して、プロシーディングスの執筆を依頼します。例年通り、JAEA-Confとして出版予定です。作成方法はこちらを参考にしてください。
要旨
It's our pleasure to announce that Symposium on Nuclear Data 2024 will be held as follows. Hosts are Nuclear Data Division, AESJ and Institute for Integrated Radiation and Nuclear Science, Kyoto University. Co-sponsors are Investigation Committee on Nuclear Data, AESJ, JAEA Nuclear Science and Engineering Center, High Energy Accelerator Research Organization. We are looking forward to your participation.
Program(http://www.aesj.or.jp/~ndd/symposium/2024program.pdf)
The session themes are as follows.
Facility tour in Institute for Integrated Radiation and Nuclear Science, Kyoto University (Research reactor and Cyclotron) will be organized in November 14th, morning (10:30 a.m. to 12:00 p.m.). If you wish to join the facility tour, choose "yes" at column of Facility tour in Registration form. Note that we offer the first come, first served basis for 20 people.
We offer travel expense support for participants. In principle, we prioritize on presenters and students. If you wish to have your travel expenses subsidized, choose "yes" at column of Travel expense support in Registration form. Note that the distribution of travel expense support is at the sole discretion of the Executive Committee due to the limited budget.
Executive committee chairperson of Symposium on Nuclear Data 2024
HORI Jun-ichi
Due date
＊It is requested that all presenters (poster and oral) write proceedings. The proceedings will be published in JAEA-Conf series. Refer to this page.
Abstract
Facility tour in Institute for Integrated Radiation and Nuclear Science, Kyoto University (Research reactor and Cyclotron) in November 14th, morning (10:30 a.m. to 12:00 p.m.).
部会賞受賞者講演
Neutron activation analysis is a highly sensitive and convenient method for qualitative analysis, but it was thought to be unsuitable for quantitative analysis. However, we have applied this method to quantitative analysis and have succeeded in measuring neutron capture cross-sections with high accuracy. By paying careful attention to uncertainty factors related to measurements, such as sample preparation in the experimental process, the neutron irradiation field, the use of Gd shielding material instead of a conventional Cd material, the development of neutron flux monitors, and the nuclear data used for analysis, we have developed a highly accurate measurement method for neutron capture cross-sections. Using this technique, we have been able to carry out systematic measurements of long-live fission products [1-3], minor actinides [4-8] and isotopes [9-13], and have succeeded in deriving cross-section data. When it was difficult to obtain a single element sample, impurities in a sample were used, and their abundance ratio was examined by mass spectrometry to quantify the amount of the target sample, resulting in successful irradiation experiments [14]. Furthermore, when a daughter nuclide is a stable one, it is impossible to derive the cross-section by conventional activation method. However, by combining activation analysis with mass spectrometry. However, by combining activation analysis and mass spectrometry, we succeeded in deriving the cross-sections, demonstrating that mass spectrometry is a very powerful method for measuring cross-sections [15]. This presentation will provide some examples of the experiments and outline how the cross-section data were derived.
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[12] S.Nakamura et al.J.Nucl.Sci.Technol.2021;58(10):1061.
[13] S.Nakamura et al.J.Nucl.Sci.Technol.2024; 61(11): 1415.
[14] S.Nakamura et al.J.Nucl.Sci.Technol.2020; 57(4): 388.
[15] S.Nakamura et al.J.Nucl.Sci.Technol.2023; 60(9): 1133.
Fission observables such as neutron multiplicity, the spectrum, and the mass/charge distributions of fission fragments/products play an important role in evaluating safety and effectiveness for nuclear applications. However, these types of data are limited due to the difficulties of experiments and their associated factors. Moreover, theoretical calculations for these observables are also challenging since the fission process is rooted in several different physical mechanisms.
We proposed a new framework for the systematic calculation of the prompt fission observables and applied it to a series of Pu isotopes [1]. This framework consists of calculations of deformation up to the scission of a nucleus (before the prompt decay) and the process of the prompt decay. The mass distribution of fission fragments and the total kinetic energy of the fragments before prompt decay were calculated using a four-dimensional Langevin model [2], which is a nuclear physics-based approach. We calculated accurate mass distributions of fission fragments by superposing two Langevin calculations, taking into account the influence of different magic shells. Then, fission observables after prompt decay were calculated in a consistent manner using the Hauser-Feshbach statistical decay model. We employed a nuclear reaction code TALYS [3,4] and used the obtained Langevin results as the inputs.
In the presentation, we will compare the calculated fission observables with the previous Langevin results, as well as experimental and evaluated data, and show that our results successfully capture the known trends and reasonably reproduce the data.
References
[1] K. Fujio, S. Okumura, C. Ishizuka, S. Chiba, T. Katabuchi, “Connection of four-dimensional Langevin model and Hauser-Feshbach theory to describe statistical decay of fission fragments”, J. Nucl. Sci. Technol. 61, 84-97 (2024).
[2] C. Ishizuka, M. D. Usang, F. A. Ivanyuk, J. A. Maruhn, K. Nishio, S. Chiba, “Four-dimensional Langevin approach to low-energy nuclear fission of
[3] A. Koning, S. Hilaire, S. Goriely, “TALYS: modeling of nuclear reactions”, Eur. Phys. J. A59, 131 (2023).
Break/休憩
To realize a decarbonized society, various organizations are developing small modular reactors and micro-reactors [1]. Toshiba Energy Systems & Solutions has been developing a MoveluX
The MoveluX
On the other hand, the Toshiba Energy Systems & Solutions Corporation measured TSL of CaH
References
[1] J. Buongiorno, et al, “The Future of Nuclear Energy in a Carbon-Constrained World”, Massachusetts Institute of Technology, MA, USA, (2018) p. 26.
[2] R. Kimura, S. Wada, “Temperature Reactivity Control of Calcium–Hydride–Moderated Small Reactor Core with Poison Nuclides”, Nucl. Sci. Eng., 193 (9), (2019) pp.1013-1022.
[3] R. Kimura, K. Asano, “Ensuring Criticality Safety of vSMR Core During Transport Based on Its Temperature Reactivity”, Nucl. Sci. Eng.,194 (3), (2020), pp.213-220.
Thermal neutron scattering law (TSL) is one of the important nuclear data that affect reactor characteristics such as criticality in the core design of thermal reactors. TSL describes neutron scattering due to atomic and molecular dynamics within materials. Evaluated nuclear data files include the latest TSLs, which were derived by molecular dynamics calculations [1]. The derived TSLs are verified using double-differential cross sections (DDSCSs) and total cross sections, which include thermal-neutron scattering. For this purpose, studies on measuring DDSCSs and/or total cross sections in the neutron energy range from thermal to a few meV have been carried out at the Materials and Life Science Experimental Facility in the Japan Proton Accelerator Research Complex (J-PARC). Preliminary results of graphite, NaCl, KCl, CaH
The present study includes the result of the ‘Development of Nuclear Data Evaluation Framework for Innovative Reactor’ founded by the Ministry of Education, Culture, Sports, Science and Technology of Japan and JSPS KAKENHI Grant Number JP24K01408
[1] Y. Abe et al., “Evaluation of the neutron scattering cross-section for light water by molecular dynamics”, Nucl. Instr. Meth., A 735, 568 (2014).
[2] A. Kimura et al., “Total and Double Differential Scattering Cross-Section Measurements of Isotropic Graphite”, EPJ Web of Conferences 294, 01002 (2024).
This talk will introduce and discuss the current status and issues of the evaluation of thermal scattering laws (TSL) in the development of the Japanese Evaluated Nuclear Data Library, JENDL.
In thermal neutron reactors, the TSL of the moderator has a significant impact on core calculations. In the JENDL series, the latest version, JENDL-5, is the first to include an original evaluation of TSL. In this evaluation, the TSL of water, a typical moderator, and hydrogen-containing organic compounds such as methane, which is used as a moderator in neutron sources, were evaluated based on molecular dynamics calculations.
However, data for crystalline materials was obtained from the ENDF/B-VIII.0 library. Crystalline materials are often used as moderators in thermal neutron reactors. Such examples are graphite in high-temperature gas-cooled reactors and molten salt reactors, and calcium hydride (CaH2) in small reactors.
Under these circumstances, we have started to establish a method for evaluating the TSL of crystalline materials with the aim of enhancing the TSL data in JENDL. As a result, we have obtained results that reproduce the experimental values of neutron scattering at J-PARC well for graphite and CaH2 by using an evaluation method based on first-principles calculations.
In addition, further improvements are underway for the TSL of light water. In order to improve reliability under high-temperature and high-pressure conditions such as reactor operation conditions, we are developing a method for evaluating TSL using molecular dynamics calculations with potentials based on first-principles calculations, which are considered to have high predictability for changes in temperature and pressure. We will also discuss the progress of evaluating TSL for light water using this method.
The analysis of the properties of nuclei in the neutron-rich region, one of the challenges in nuclear reactions, is very important in the study of superheavy element synthesis and the r-process in astrophysics. However, most nuclei in this region are not yet known [1]. As a means of reaching this region, a method based on multinucleon transfer reactions has been proposed [2].
At present, experimental studies on multinucleon transfer reactions have intensified with the development of accelerators and other experimental techniques [3]. However, the physical mechanism of the multinucleon transfer reaction itself has not been completely clarified. In this respect, it is essential to contribute to experimental studies through theoretical approaches.
In this study, a theoretical dynamical model applying the Langevin equation was used to analyze multinucleon transfer reactions targeting a spherical nucleus. Correlations between the particle emission angle and the number of transferred nucleons, which can be measured experimentally, and the angular momentum of the product nucleus, which cannot be measured experimentally, were investigated. This is important for multinucleon transfer reactions because the survival probability depends on the angular momentum of the produced nuclei. We report on the correlation of each parameter since the calculations were performed in a reaction using an Xe beam and a target nucleus.
References
[1] V. Zagrebaev, A. Karpov and W. Greiner, J. Phys: Conf. Ser. 420, 012001 (2013).
[2] V. Zagrebaev, W. Greiner, Phys. Rev. Lett. 101, 122701 (2008).
[3] Y. X. Watanabe et al., Phys. Rev. Lett. 115, 172503 (2015).
Recently, multi-nucleon transfer (MNT) reactions have attracted attention as a method of producing neutron-rich nuclei [1]. However, the reaction mechanism is not yet well understood due to its novelty and complexity. In this study, we construct a dynamical model that describes the dynamics of the MNT reaction and verify the model by comparing it with experimental data to clarify the reaction mechanism.
As a first step, to clarify the reaction mechanism, the angular momentum of the evaporation residue (ER) produced by MNT reaction and the emission angle of projectile-like nuclei were investigated. It is known that the fission process of ERs depends on their angular momentum, and the information of angular momentum is important to know the survival probability of the ER [2]. The emission angles of projectile-like nuclei are also experimentally observable data, which is necessary information for angular momentum prediction. There is a correlation between angular momentum and the emission angle of projectile-like nuclei. The present study aims to deal with the production of neutron-rich nuclei in the heavy and superheavy elemental regions. In this work, MNT reaction in the
The theoretical model we use is based on the two-center shell model to describe the configuration of nuclei [3]. The time evolution of the configuration is described by the multidimensional Langevin equation [4]. In this presentation, we show the effect of the collision angle in the case of a deformed target nuclei and discuss its influence on the reaction mechanism. The effect of the angular momentum of ERs on the following fission process is also discussed.
References
[1] V. Zagrebaev, et al., “Superheavy nuclei and quasi-atoms produced in collisions of transuranium ions” Phys Rev C 73, (2006) 031602.
[2] S. Tanaka, et al., “Angular momentum transfer in multinucleon transfer channels of
[3] J. Maruhn and W. Greiner, “The asymmetrie two center shell model” Z. Phys 251, (1972) 431.
[4] V. Zagrebaev and W. Greiner, “Unified consideration of deep inelastic, quasi-fission and fusion–fission phenomena” J. Phys. G 34, (2007) 2265-2277.
A shielding experiment campaign using NE213 liquid scintillator was conducted to measure high-energy neutrons at the CHARM facility located in CERN [1]. From the neutron spectra obtained with the NE213 scintillator, it was observed that the high-energy components originated from nuclear reactions between the Cu target and 24 GeV/c proton beam.
However, significant discrepancies between measured and calculated data were observed, not only in their shapes but also in integrated values within the high-energy region above 100 MeV. The reason is that the maximum proton energy to fully stop within 12.7 cm thickness of the NE213 scintillator is about 124 MeV according to the SRIM calculation. Thus, the recoil protons having more than this energy pass through the scintillator, with depositing only a portion of their energies. There is a need to develop a new detector that is more sensitive to energies above 124 MeV.
Using PHITS simulation, the response differences between CsI(Tl) and NE213 scintillators were evaluated to clarify the high-energy neutron detection. The dimension of the CsI(Tl) crystal and NE213 are 5 cm x 5 cm x 30 cm-length and
References
[1] E.Lee, “Energy spectra of neutrons penetrating concrete and steel shielding blocks from 24 GeV/c protons incident on thick copper target”, NIMA 998 (2021).
To develop technologies for criticality safety management during the fuel debris retrieval at the Fukushima Daiichi Nuclear Power Plant, we conduct experiments under various core conditions assumed for fuel debris. JAEA modified the Static Experiment Critical Facility (STACY) from a solution fuel system to a light-water moderated heterogeneous system for critical experiments to study the criticality characteristics of fuel debris. After the modification, STACY was operated to inspect its designed performance on reactor operation, and the first criticality was achieved on April 22, 2024.
In this study, we performed criticality calculations of STACY's critical cores using several nuclear data libraries and compared their results. The five core patterns in a series of performance testing were calculated neutron multiplication factor with the measured critical water levels: (1) 277 fuel rods with a water level of about 70 cm, (2) 253 fuel rods with a water level of about 110 cm, (3) 253 fuel rods with an irradiation sample in the center of the core for thermal power calibration with a water level of about 120 cm, (4) 241 fuel rods with a water level of about 70 cm, and (5) 213 fuel rods with a water level of about 110 cm. Fuel rods are cylindrically loaded on a grid plate with grid intervals of 1.50 cm for cores (1), (2) and (3), and of 1.27 cm with skipping one by one to achieve fuel intervals of 2.54 cm for cores (4) and (5).
We calculated neutron effective multiplication factors of each core using MVP2 with JENDL-4.0, JENDL-5, and ENDF/B-VII.1. Furthermore, in order to analyze the differences between libraries, a comparison was made for representative nuclides by replacing the nuclear data of each nuclide with JENDL-5 in the calculations using JENDL-4.0.
The result using JENDL-4.0 showed that the effective neutron multiplication factor correspond within 3σ for cases of (1), (2), and (3). However, it overestimated about 69 pcm for case (4) and about 33 pcm for case (5). JENDL-5 overestimated all patterns, 195 pcm in maximum.
In this presentation, detailed critical data for all pattern cores and evaluated trends for each nuclide will be presented.
Tungsten is applied to a target at proton accelerator facilities, e.g., ESS and COMET (J-PARC). Additionally, tungsten is used as a shielding material, such as the ADS facility by JAEA [1]. Thus, activation of tungsten by high-energy protons receives attention because residual
As a result, a total of 140 nuclides via the
References
[1] Iwamoto H., Meigo S., Nakano K.
[2] Titarenko Yu. E., Batyaev V. F., Titarenko A. Yu.
[3] Michel R., Gloris M., Protoschill J.
[4] Takeshita H., Meigo S., Matsuda H.
[5] Watanabe Y., Kosaka K., Kunieda S.
[6] Sato T., Iwamoto Y., Hashimoto S.
We studied the decay branching ratios of
Reference
[1] O. Lebeda, F.G. Kondev, J. Cervenak, “Branching ratio and
Recently nuclear medicine therapy using nuclides emitting
The developed system can calculate and illustrate arbitrary nuclide production cross sections and TTYs from light particle (
Using this system, we investigated the optimal production method for Auger electron emitters. For example, when the incident energy is from 1 to 50 MeV and a natural composed target is used, the production cross section of
References
[1] D. Filosofov, E. Kurakina, V. Radchenko, “Potent candidates for Targeted Auger Therapy: Production and radiochemical considerations”, Nucl. Med. Biol. 94-95, (2021), pp. 1-19.
[2] O. Iwamoto, N. Iwamoto, S. Kunieda
Nuclear security at nuclear reactor facilities is a significant concern, particularly with regards to the theft and smuggling of nuclear material, as well as sabotage of the facilities. One crucial task to prevent these security incidents is the development of non-destructive detection techniques for identifying nuclear material. Although numerous techniques have been proposed, further study is still needed to meet the necessary requirements.
Previous research has proposed to employ a photon beam from the inverse Compton scattering using a large accelerator [1]. However, this approach requires a large accelerator facility.
In comparison to previous research, the present research aims to develop a new system using a small accelerator. This research uses the nuclear reaction
References:
[1] R. Kimura, et al., J. Nucl. Sci. Technol.
Measurement of high-energy gamma radiation in high-dose-rate environments is difficult due to problems such as the dead time of a detector. However, there is a need for measurement techniques under high dose rates, such as radiation detection and nuclear data measurement inside nuclear reactors and in radiation contaminated areas. In particular, this issue must be solved in applications such as critical monitoring in handling nuclear debris and neutron cross section measurement of radionuclides. Major component of gamma-rays in these applications is relatively low energy gamma-rays (several hundred keV). Thus, this research project is to solve the issue by developing a gamma-ray detector that is sensitive to only high energy gamma-rays based on a new detection principle that employs electron-positron pair production induced by high-energy gamma-rays and detects annihilation gamma-rays. The detector system consists of a pair-production target and a pair of gamma-ray detectors which detect annihilation gamma-rays from the pair production target. In the present work, the geometrical configuration and the pair production target were optimized by Monte Carlo simulation.
We are developing a measurement system for the simultaneous determination of (n,
Strontium-88, which has a neutron magic number of 50, is important in s-process nucleosynthesis because it acts as a bottleneck in the s-process reaction network due to the small (n,
References
[1] F. Käppeler et al., Astrophys. J.
[2] T. Katabuchi et al., Phys. Rev. C. 108. 10.1103 (2023).
To calculate reliably and accurately concentrations and activities for nuclides generated or depleted by fission and radioactive decay in nuclear fuel, it is necessary to use the updated nuclear decay data such as half-lives, branching ratios, and
An example is the
JENDL-5 Decay Data File (DDF) is one of the sub-libraries of JENDL-5 and was publicized in 2021. Most of the data in JENDL-5 DDF were taken from ENSDF. We verified the values in JENDL-5 DDF by using our newly evaluated values. For example, the half-life of
References
[1] M. Wang et al. “The AME2020 atomic mass evaluation (II). Tables, graphs and references”, Chin. Phys. C45, 030003 (2021).
Multinucleon transfer (MNT) reactions have attracted attention in the field of nuclear physics and astronomical nucleosynthesis as a reaction which produces neutron-rich nuclei as evaporation residues (ER). But detailed feature of reaction mechanism is not understood. Detailed experimental data are necessary to develop a model to guide an optimal reaction and experimental condition. We have started the measurement of ER cross sections in various conditions. Experiments were carried out using the JAEA Recoil Mass Separator (JAEA-RMS[1]). As a first attempt, we studied the reaction
References
[1] H. Ikezoe et al., Nucl.Instrum.Methods Phys.Res.A
Nuclide inventory calculations with MVP-BURN and JENDL-4.0 were performed for the twelve fuel samples taken from two 15×15 PWR fuel assemblies irradiated in Three Mile Island (TMI) Unit 1[1,2]. The calculated results of
References
[1] Radulescu G, Gauld IC, Ilas G. SCALE 5.1predictions of PWR spent nuclear fuel isotopic compositions. Oak Ridge (Tennessee): Oak Ridge National Laboratory; 2010. (ORNL/TM-2010/44).
[2] Gauld IC, Giaquinto JM, Delashmitt JS. Re-evaluation of spent nuclear fuel assay data for the Three Mile Island unit 1 reactor and application to code validation. Annals of Nuclear Energy. 2016 Jan; 87(2):267-281.
The JENDL-5 [1] covariance library, covering 105 nuclides, was generated using the AMPX-6 code system [2]. Additionally, a covariance library was also generated from ENDF/B-VIII [3] for JENDL-5 nuclides lacking covariance data. These covariance libraries facilitated the estimation of keff uncertainty attributable to the nuclear data of the Indonesian RSG GAS Multipurpose Research Reactor (clean first core criticality experiments). The RSG GAS is a material testing reactor, characterized by its beryllium reflector, light-water moderator, and low-enriched uranium (19.75 wt.%) fuel. Sensitivity coefficients for the ten dominant reaction types required for uncertainty evaluation were derived using the MCNP6 code [4]. The estimated keff uncertainties due to nuclear data are 620 pcm, 644 pcm, and 637 pcm for JENDL-5 only, JENDL-5 & ENDF/B-VIII.0, and ENDF/B-VIII.0 covariance libraries, respectively, which are comparable with the keff ([C/E-1]) values.
References
[1] Iwamoto O. et al. (2023), “Japanese Evaluated Nuclear Data Library version 5: JENDL-5,” J. Nucl. Sci. Technol., 60(1), pp. 1-60.
[2] Wiarda D. et al. (2016), “AMPX-6: A Modular Code System for Processing ENDF/B,” ORNL/TM-2016/43.
[3] Brown D. A. et al. (2018), “ENDF/B-VIII.0: the 8-th Major Release of the nuclear reaction data library with CIELO-Project Cross Sections, New Standards and Thermal Scattering Data,” Nuclear Data Sheets 148 (2018) pp 1-42.
[4] Werner C. J. et al. (Ed.) (2017), “MCNP User’s Manual; Code Version 6.2,” LA-UR-1729981.
The experiments at JAEA have produced a wide variety of nuclei and various excited states through multi-nucleon transfer reactions and successfully observed their fission [1]. The fission fragment mass distributions (FFMDs) obtained in this experiment show a mass asymmetry even in the high excitation energy region. This phenomenon can be explained by multi-chance fission (MCF). In a previous study [2], the neutron emission multiplicity was obtained by the GEF code [3] and then the fission process was calculated by the dynamical model method to incorporate the MCF effect and reproduce the experimental data of FFMDs with high accuracy. However, the above method does not take into account neutron emission during the fission process. Therefore, our group has been developing a model that can describe neutron emission in the fission process by incorporating the neutron evaporation process in the dynamical model [4]. In fact, FFMD calculations can be performed taking into account the decrease in excitation energy due to neutron emission and the accompanying change in the shell correction energy. In this study, we have further improved the model so that it can also take into account variation in the liquid drop model potential due to neutron emission, and we report the results.
References
[1] K. Hirose, et al., Phys. Rev. Lett. 119, 222501 (2017)
[2] S. Tanaka, et al., Phys. Rev. C 100 064605 (2019)
[3] K.-H. Schmidt, et al., Nucl. Data Sheets 131 107-221 (2016)
[4] R. Yamasaki, et al., proceedings of the 2020 Symposium on Nuclear Data.
Diminishing the amount of high-level nuclear waste accumulated through reactor operation has always been a one of the most important obstacles regarding the long-term implementation of nuclear technologies. While the main efforts have been targeting minor actinides (MAs), long-lived fission products (LLFPs) remain another clear target for which several solutions have already been proposed. Among these solutions is the nuclear transmutation of LLFPs by means of fast nuclear reactors, the feasibility of which has been proven in recent studies [1,2]. For this approach, accurate nuclear data in the keV-neutron region are required for most LLFPs such as
Neutron filter experiments were performed using the NaI(Tl) spectrometer of the ANNRI beamline at J-PARC to determine the neutron capture cross section at the neutron energies of 51.5 and 127.7 keV. A sample containing 404 mg of
In this study, the results of the
[1] Chiba S, Wakabayashi T, Tachi Y, et al. Method to Reduce Long-lived Fission Products by Nuclear Transmutations with Fast Spectrum Reactors. Sci Rep. 2017;7:1–10.
[2] Wakabayashi T, Tachi Y, Takahashi M, et al. Study on method to achieve high transmutation of LLFP using fast reactor. Sci Rep . 2019;9:2–12.
[3] Iwamoto N. Evaluation of Neutron Capture Cross Sections and Covariances on
[4] Rovira G, Kimura A, Nakamura S, et al. Neutron capture cross section measurement of
Technetium-99 is a long-lived fission product (LLFP) which undergoes
The experiment was conducted at the Accurate Neutron-Nucleus Reaction measurement In-strument (ANNRI) beamline at the Materials and Life Science Experimental Facility (MLF) at the Japan Proton Accelerator Research Complex (J-PARC). Capture
References:
[1] G. Noguere et al. Phys. Rev. C, 102, 015807 (2020).
[2] N. Iwamoto Journal of Nuc. Sci. and Tech., Vol. 49, No. 2 (2012).
[3] D. Rochman et al. Nuc. Sci. and Eng., 158, 68-77 (2008).
[4] N. Iwamoto et al. EPJ Web of Conferences, 146, 02049 (2017).
In recent years, the synthesis of new superheavy element
In this presentation, we mainly discuss the effect of Q-value, that depends on the mass tables, on rising positions of cross sections’ excitation functions and the associated difference in evaporation residue cross sections.
[1] Yu. Ts. Oganessian, et al., “Measurements of cross sections and decay properties of the isotopes of elements 112, 114, and 116 produced in the fusion reactions
[2] Yu. Ts. Oganessian, et al., “Synthesis of the isotopes of elements 118 and 116 in the
[3] Y. Aritomo, et al., “Dynamical approach to heavy-ion induced fission using actinide target nuclei at energies around the Coulomb barrier”, Phys. Rev. C 85, 044614 (2012).
[4] K. Hagino, et al., “A program for coupled-channel calculations with all order couplings for heavy-ion fusion reactions”, Computer Physics Communications 123 (1999) 143-152.
[5] Y. Aritomo, et al., “Fluctuation-dissipation model for synthesis of superheavy elements”, Phys. Rev. C 59, 769, February 1999.
The US nuclear safety analysis code system SCALE6.2 [1] is also widely used in Japan, but the bundled AMPX continuous energy libraries are produced only from the US nuclear data library ENDF/B. Thus I produced an AMPX continuous energy library of JENDL-5 with the AMPX-6 code [2] bundled in SCALE6.2. In this nuclear data processing I found out that several produced AMPX continuous energy files of the thermal scattering law data in JENDL-5 had strange cross section data. I examined reasons why the strange cross section data were produced in detail and specified that an inadequate processing method of the thermal scattering law data in AMPX-6 caused the strange cross section data. I improved AMPX-6 and obtained adequate AMPX continuous energy files of the JENDL-5 thermal scattering law data.
References
[1] (Ed.) W.A. Wieselquist, R.A. Lefebvre, M.A. Jessee, “SCALE Code System”, ORNL/TM-2005/39 Version 6.2.4 (2020).
[2] D. Wiarda, M.E. Dunn, N.M. Greene, M.L. Williams, C. Celik, L.M. Petrie, “AMPX-6: A Modular Code System for Processing ENDF/B”, ORNL/TM-2016/43 (2016).
The Japan Aerospace Exploration Agency (JAXA) plans to develop the charged particle spectrum in space to observe the radiation dose for astronauts for Artemis programs. Also, the National Institute of Information and Communications Technology (NICT) plans to develop a spectrum to observe solar flares precisely. Both spectrometers based on Cherenkov radiation are aimed to observe the charged particles up to about 1 GeV. Those institutions want to examine the spectrometers using J-PARC accelerators. To match their requirements and fulfill the safety without disturbing the accelerator operation, a method using beam scattering at the window was developed in J-PARC, which gives us quasi-monoenergetic protons by placing the device at a small angle regarding the incident proton directions. This technique allows us to use the double differential cross sections in several GeV regions, which is explained in this session.
Also, many small space satellites have been planned for future communications. The need for protons for space use has drastically increased, as the need to test the semiconductor devices mounted on the satellites in space environments against failures due to single-event Effects (SEEs). Therefore, the needs are expected to increase drastically worldwide.
For the study of material damage under the beam irradiation circumstance of accelerator-driven systems (ADS), the Japan Atomic Energy Agency (JAEA) had planned to construct a Transmutation Experimental Facility Target Facility (TEF-T) using J-PARC Linac 400 -MeV proton beams and the LBE spallation target. The task force for evaluating partitioning and transmutation technology in the MEXT concluded that the facility should be considered to maximize the advantages of using Linac to meet users' various needs. The proton irradiation facility, a successor of TEF-T, will be constructed to supply the proton beam applications for space use as one of the purposes. In this session, the beam facility, including another purpose, will be explained.
The Heavy-Water Thermal Neutron Facility at the Kyoto University Research Reactor (KUR) has been used for boron neutron capture therapy (BNCT) since 1974. After facility upgrades in 1996, it was renamed the Heavy-Water Neutron Irradiation Facility (HWNIF), and the neutron energy spectrum was measured using the multifoil activation method. In 2010, KUR switched from high- to low-enrichment fuel, but the neutron spectrum in the KUR-HWNIF has not been reevaluated precisely since then. Detail of neutron energy spectrum data in BNCT irradiation fields is essential for various purposes, such as comparing irradiation characteristics across BNCT facilities, developing detectors and spectrometers, and calculating absorption dose.
This study aimed to reevaluate the neutron energy spectrum for the standard epithermal-neutron irradiation mode at KUR-HWNIF using the multifoil activation method. The previous evaluation irradiated the multifoil at 5 MW for 10 hours. Currently, KUR operates at 1 MW for 47 hours and 5 MW for only 6 hours each week. Due to limited 5 MW operation time, we utilized 1 MW power to irradiate the multifoil. With a lower thermal operation power, some foils used in the previous evaluation yielded lower counts during the measurements. In this study, the types of foils used for irradiation, the irradiation time, and the irradiation setup were adjusted from a previous study to obtain measurable results from the irradiated foils. \par
The neutron energy spectrum was evaluated using selected foils and optimized irradiation times, suited for measuring the spectrum in the epithermal and fast neutron ranges, which are predominant in the standard epithermal-neutron irradiation mode. The neutron energy spectrum unfolding process was performed by UMG package which included MAXED and GRAVEL unfolding code [2]. The previous evaluated nominal neutron energy spectrum [1] data was used as initial guess for unfolding process. Comparing with two different unfolding result of UNG package, GRAVEL gave a better evaluation result without any irregularities. Based on the reevaluated results from GRAVEL unfolding code, the epithermal- and fast-neutron fluxes increased by approximately 34% and 19%, respectively. The neutron absorption dose rate at evaluation point was approximately 17% lower than the previous one; however, it remained acceptable from the perspective of BNCT biological irradiation.
References
[1] Y.Sakurai, T.Kobayashi, “Spectrum evaluation at the filter-modified neutron irradiation field for neutron capture therapy in Kyoto University Research Reactor”, Nucl Instrum Methods Phys Res A 531, (2004), pp. 585-595.
[2] M.Reginatto, “The ‘Few-Channel’ Unfolding Programs in the UMG Package: MXD FC33 and GRV FC33 and IQU FC33”, 215 Technical Report, Braunschweig, (2004).
The mass and total kinetic energy (TKE) distribution of fission fragments brings essential information on fission dynamics. The fission dynamics have been investigated theoretically with the multi-dimensional Langevin approach, in particular, for actinide nuclei [1]. In this approach, the deformation potential plays a key role in determining the fragment distribution. In order to understand the results of multi-dimensional Langevin calculations, a specific analysis of the structure of the deformation potential is essential. In general, double-humped barrier structures are known for actinide nuclei, but triple-humped barriers are predicted for some nuclides. Identification of the positions and heights of saddle points corresponding to second and third barriers in the multi-dimensional potential space will explain the mass-TKE distributions obtained by Langevin calculations and contribute to the understanding of the origin of various fission modes.
In this study, to investigate the structure of the energy surface in a multi-dimensional deformation space, we focus on the positions and heights of minima and saddle points. The deformation space is described by the Cassini parameter, which is composed of an overall elongation
In this presentation, the results for Fm isotopes will be presented, since it is known that the mass distribution changes from asymmetric to symmetric between
References
[1] K. Okada, T. Wada, and N. Carjan, “Four-dimensional Langevin approach to fission with Cassini shape parameterization”, EPJ Web of Conferences 284, 04018 (2023).
[2] P. Möller, A.J. Sierk, T. Ichikawa, A. Iwamoto, R. Bengtsson, H. Uhrenholt, and S. Åberg, “Heavy-element fission barriers”, Phys. Rev. C 79, 064304 (2009).
In high-energy and high-intensity neutron environments, such as the fusion reactor blanket, large angle scattering reaction cross sections significantly affect neutron transport calculation results. C. Konno has identified discrepancies between experimental and calculated values in the blanket benchmark experiments in Japan Atomic Energy Agency (JAEA) [1]. Therefore, benchmarking studies for large angle scattering cross sections are indispensable. The authors’ group developed a benchmark experimental system utilizing the foil activation method to validate these cross sections [2]. Four experiments for a certain sample were conducted using two shadow bars composed of conical irons with and without the sample to extract large angle scattering neutrons.
In the previous study, we performed a benchmark experiment for lithium using hafnium as the activation foil. However, due to lithium's low mass, detecting large angle scattering neutrons was challenging, leading to considerable experimental errors caused by neutrons scattered from walls and other surrounding materials. In that study, to investigate whether large angle scattered neutrons from lithium could be detected, the counts obtained with the Ge detector and the associated statistical errors were calculated when various elements were used as the activation foil, concluding that hafnium was the best activation foil. However, the statistical error estimation did not account for background contributions, a significant factor in the experiment. Furthermore, the cooling and measurement times required further optimization.
In this study, we recalculated the statistical error by considering background effects and recalibrating the cooling time, and obtained statistical errors at various measurement times. Six isotopes were selected for measurement based on factors such as isotope abundance, activation cross section, threshold value, and half-life. The reaction rate for each activation reaction was calculated using MCNP5, the Ge detector counts were determined, and the statistical error was recalculated. Our results indicated that using the
In the future we will develop an experimental system that could further minimize statistical errors by optimizing the materials and configurations of surrounding components of the experimental assembly, and carry out benchmark experiments with the assembly for large angle scattering cross section for lithium using magnesium as the activation foil to obtain highly accurate experimental results.
References
[1] S. Ohnishi, K. Kondo, C. Konno
[2] N. Hayashi, S. Ohnishi, I. Murata
Understanding nuclear fission is critical for updating and improving the nuclear data. In particular, significant questions remain regarding fission near the mass number
Recently, measurements of the fragment mass and total kinetic energy (TKE) distributions for the fission of
In this study, we calculate the fission process of
References
[1] K. Nishio \textit{et al}., “Competition between mass-symmetric and asymmetric fission modes in
[2] V. V. Pashkevich, “On the asymmetric deformation of fissioning nuclei”, Nucl. Phys. A \textbf{169}, (1971), pp. 275-293.
The Intranuclear Cascade model has been improved for calculating alpha induced reaction. Alpha inelastic reaction is dominant for the alpha incident reaction, so that its cross section must be calculated accurately. However, it is difficult to optimize the inelastic reaction and fragmentation reaction for all fragment channel in parallel. Therefore, in this study, we focus on the inelastic reaction only and calculate the cross section for alpha particles using the break-up model having dependency of target mass density. The calculation results were compared with experimental data of double differential cross sections for the alpha particle at incident energy of 230 MeV/u on
The intranuclear cascade model has been improved for calculating proton-induced reactions; the calculation results near 0 degrees remain unsatisfactory. It is known that several types of giant resonances exist near 0 degrees. In this study, giant resonances were incorporated, and comparisons with experimental data were conducted to examine mass and energy dependencies. The experimental data includes the double differential cross-section for the reactions, for example,
The four-dimensional Langevin model [1,2,3] is a nuclear physics model that allows for the independent treatment of each fission fragment and accurately reproduces the total kinetic energy (TKE). However, due to the multidimensional nature of the model, it is challenging to quantitatively determine which physical quantities exhibit a strong correlation with nuclear fission. In this study, we applied Principal Component Analysis (PCA) [4] to project the fission trajectory data obtained from the four-dimensional Langevin model onto a space defined by principal component vectors, aiming to identify the most significant physical quantities. Specifically, we used 1000 events for each of the standard and super-short fission modes of
References
[1] M.D. Usang, F.A. Ivanyuk, C. Ishizuka, S. Chiba, Sci. Rep. 9, 1525 (2019).
[2] C. Ishizuka, M.D. Usang, F.A. Ivanyuk, J.A. Maruhn, K. Nishio, S. Chiba, Phys. Rev. C 96, 064616 (2017).
[3] C. Ishizuka, X. Zhang, K. Shimada, M. Usang, F. Ivanyuk, S. Chiba, Front. Phys. 11, 1111868 (2023).
[4] C.M. Bishop, “Pattern Recognition and Machine Learning”, (Springer-Verlag, Berlin, Heidelberg, 2006), Chap. 12, ISBN 0387310738.
At present, using the fusion reaction between the projectile and target nuclei, up to Og has been successfully synthesized and projects to synthesis of new superheavy elements (SHEs) are underway at several facilities around the world. However, the synthesis probability of SHEs is extremely low, and most of them undergo quasi-fission, which cannot sustain a compound nucleus after contact. Therefore, this study aims to elucidate the complex dynamics of quasi-fission by systematically investigating the reaction mechanism.
To understand the dynamics of the fusion process, we focused on the correlation between fragment mass and its emitting angle of quasi-fission [1]. Our group has succeeded in reproducing the mass angular distribution (MAD) of the emitted nuclei by using a dynamical model, considering the deformation of the target nuclei [2]. The dynamical model is based on the liquid drop model and the shell effect to determine the shape of the nucleus and its potential at that time, and the time evolution of the shape from fusion to fission can be traced by solving the langevin equation. Calculations of fusion reactions require fitting of indefinite parameters from experimental data, such as energy dissipation due to friction between nuclei and the transition from diabatic to adiabatic potentials, which are suitable for equilibration of the system.
In this study, we calculated the 42 systems experimented in Ref. [1] under identical conditions except for the number of nucleons and summarized the MAD. Among these, we correct the uncertain parameters and systematically evaluate
References
[1] R. du Rietz et al., “Mapping quasifission characteristics and timescale in heavy element formation reactions”, Phys. Rev. C 88, 054618 (2013)
[2] Shota Amano et al., “Effects of neck and nuclear orientations on the mass drift in heavy ion collisions”, Phys. Rev. C 109, 034603 (2024)
Activation analyses are essential in planning and execution of reactor decommissioning, where the ORIGEN-2 and ORIGEN-S codes are often used in Japan. This presentation points out problems in these codes and introduces the ORIGEN code, which is bundled in the US nuclear safety analysis code system SCALE6.2 [1] or later. ORIGEN solves most of the problems but SCALE6.2 bundles only the libraries from the nuclear data library ENDF/B-VII.0 or later. Thus I produced new libraries [2] for the ORIGEN code from JENDL-5. I also present remarks on calculations with the two-dimensional Sn code DORT [3] which is often used to calculate neutron spectra for activation analyses.
References
[1] (Ed.) W.A. Wieselquist, R.A. Lefebvre, M.A. Jessee, “SCALE Code System”, ORNL/TM-2005/39 Version 6.2.4 (2020).
[2] C. Konno, M. Kochiyama, H. Hayashi, “Generation and verification of ORIGEN and ORIGEN-S activation cross-section libraries of JENDL-5 and JENDL/AD-2017”, Mechanical Eng. Journal, Vol. 11, Paper No.23-00386 (2024).
[3] ORNL RSICC, “DOORS3.2a: One, Two- and Three-Dimensional Discrete Ordinates Neutron/Photon Transport Code System”, RSIC CODE PACKAGE CCC-650 (2007).
Nuclear data are essential for the research and development of nuclear energy systems and accelerator facilities, and applications involving radioactive isotopes. However, the increasing complexity of theoretical models and the demands of large-scale computations have made sustainable nuclear data evaluation challenging with limited human resources. To overcome these difficulties and continue providing reliable nuclear data, it is crucial to advance nuclear data evaluation methods.
In this talk, I will explore possible solutions to these issues through Bayesian machine learning, using examples from our recent work. [1,2].
References
[1] H. Iwamoto, S. Meigo, K. Sugihara, “Comprehensive estimation of nuclide production cross sections using a phenomenological approach”, Phys. Rev. C,
[2] H. Iwamoto, M. Niikura, R. Mizuno, “Comprehensive Bayesian machine learning approach to estimating the total nuclear capture rate of a negative muon”, Phys. Rev. C (submitted).
The negative muon (
In preparation
In the TEPCO’s Fukushima Daiichi Nuclear Power Plant accident, fuel debris was formed by fuel melting and mixing with in-core structures. Although the detailed properties of the fuel debris are still unknown, it is thought to contain materials such as iron and concrete. Then, in order to understand the criticality characteristics of fuel debris, JAEA is conducting a comprehensive numerical analysis assuming the composition of fuel debris containing concrete and iron. However, integral experimental data including these materials are scarce, and the validation of the analytical results has not been fully investigated. Thus, JAEA modified the criticality facility STACY in order to obtain experimental data that will contribute to the validation. This report describes the outline and status of the modified-STACY, and the plan is also presented.
The modified-STACY core is assembled in the open-top core tank using fuel rods and light water moderator. Each fuel rods consists of a zirconium alloy clad tube (9.5 mm outer diameter) and UO
Experiments on the core containing the structural materials will be conducted in January 2025. In these experiments, stainless steel rods of the same size as the fuel rods and Al cladding tubes of the same size filled with a concrete simulant will be used as the experimental apparatus to simulate the structural materials. By using them, the effects of contaminants such as iron, silicon, and calcium on criticality will be investigated. In addition, the presentation will also report on plans after the debris experiment is completed.
Institute for Integrated Radiation and Nuclear Science, Kyoto University (KURNS) has been operated two research reactors, namely, Kyoto University Research Reactor (KUR) and Kyoto University Critical Assembly (KUCA).
KUR whose maximum power is 5MW starts its operation in 1964 and it has been utilized mainly for supplying fast and thermal neutron in various kinds of research field, however, Kyoto University decided to stop its operation in May-2026 because of several reasons; treatment of spent fuels, facility aging problem, increasing operation cost and so on. After shutdown, we will soon submit decommissioning application of KUR to Nuclear Regulation Authority (NRA) and, firstly, all spent fuels are planning to ship to U.S.A.
KUCA whose maximum power is 100W starts its operation in 1974 and it has been utilized for basic reactor physics experiments and nuclear human resources development through student education experiments. It had used highly enriched uranium (HEU) fuels both at the solid moderated core and the light water moderated core, and according to the reduced enrichment program for research reactors conducted by U.S.A., all HEU fuels was sent back to U.S.A. until 2022 and new low enriched uranium (LEU) fuels have been prepared for KUCA including obtaining license from NRA. For light water moderated core, uranium silicide plate type fuels have been already fabricated in a foreign fuel company and some of them were just transported to KUCA last month. For solid moderated core, world-first uranium-molybdenum alloy coupon type fuels are now under fabrication. We are planning to restart operation of KUCA in 2025 and will utilize it for research and student education.
KURNS owns other radiation facilities such as a hot laboratory where unsealed radioactive material and nuclear materials can be handled for research purpose and operates accelerators; the electron linear accelerator, the proton cyclotron and so on. After shutdown of KUR, we will continue to utilize those unique radiation facilities as joint use research center.
The Japan Atomic Energy Agency (JAEA) has been developing various non-destructive assay (NDA) techniques [1] to verify nuclear materials. However, one major challenge in NDA is measuring highly radioactive materials. To address this, neutron resonance analysis (NRA) has been proposed as a promising active neutron NDA technique. NRA combines neutron resonance transmission analysis (NRTA) [2] with neutron resonance capture analysis (NRCA) [2, 3] and the newly introduced neutron resonance fission neutron analysis (NRFNA) [4]. In an NRA system, a pulsed neutron beam, in conjunction with the neutron time-of-flight (TOF) method [2], is used to measure transmitted neutrons, capture gamma-rays, and fission neutrons from a fissile material sample. The system employs a GS20 glass scintillator for detecting transmitted neutrons, while a pulse shape discrimination (PSD) plastic scintillator is used to detect and discriminate between capture gamma-rays and fission neutrons. The positions and depths of resonance peaks or dips in the TOF spectra are determined by the neutron cross sections of nuclides and their amount in the sample. Therefore, to accurately identify and quantify fissile materials based on these spectra, the use of the evaluated nuclear data library is essential. This presentation will provide a detailed overview of the NRA project and discuss the critical role of accurate nuclear data in its success.
References
[1] M. Koizumi, Non-destructive Nuclear Detection and Measurement Technology Development Projects of JAEA for Nuclear Non-proliferation and Security, Proceedings of the INMM & ESARDA Joint Virtual Annual Meeting. 201, (2021).
[2] P. Schillebeeckx, B. Becker, H. Harada, and S. Kopecky, Neutron Resonance Spectroscopy for the Characterization of Materials and Objects, JRC Science and Policy Reports, JRC 91818, EUR 26848 EN (2012).
[3] H. Postma and P. Schillebeeckx, Neutron resonance capture and transmission analysis, Encyclopedia of Analytical Chemistry (New York: John Wiley & Sons Ltd.), (2009).
[4] K. Hironaka, J. Lee, M. Koizumi, F. Ito, J. Hori, K. Terada, and T. Sano, Neutron resonance fission neutron analysis for nondestructive fissile material assay, Nucl. Instr. Methods Phys. Res. A. 1054, (2023), 168467
Delayed gamma ray assay (DGA) is a promising technique for estimating fission rate ratio of uranium (U) and plutonium isotopes contained in spent nuclear fuel [1]. The accuracy of DGA relies on that of the data of fission product yield and decay (FPY & FPD). To enhance the accuracy of the FPY & FPD data, differential measurements have been conducted in the LINAC neutron source facility in KURNS. In the facility, pulsed electron beam with time width of 5
An U – aluminum sample placed 11.4 m form the target was irradiated by the moderated neutrons and
Radio-activities of FPs and emission rates of
References
[1] D. C. Rodriguez, T. Bagucarska, M. Koizumi, et al., NIM-A 997, 165146, 2021.
[2] J. Katakura, JAEA-Data/Code 2011-025, 2012.
Radioisotopes (RIs) are widely used as tracers and radiation sources in basic research in physics, chemistry and biology, as well as in medical, agricultural and industrial applications. We are developing production technologies for useful RIs and promoting RI application research in various research fields using the heavy-ion accelerators in the RIKEN RI Beam Factory [1–3]. More than 100 RIs covering almost the entire periodic table of elements, from beryllium (Be) to element 107, bohrium (Bh) have been produced with the RIKEN AVF cyclotron and the RIKEN linear accelerator. On the other hand, RIs of a large number of elements (multitracer) are simultaneously produced from metallic targets such as
References
[1] H. Haba et al., in Handbook of Nuclear Chemistry (2nd ed.), edited by A. Vértes et al., Vol. 3, Springer, (2010), pp. 1761–1792.
[2] H. Haba, J. Part. Accel. Soc. Jpn.
[3] RIKEN Accel. Prog. Rep., each volume, Sect. Radiochemistry and Nuclear Chemistry, and the references cited in it (http://www.nishina.riken.jp/researcher/APR/index_e.html).
[4] H. Haba, Drug Deliv. Syst.
[5] X. Yin et al., RIKEN Accel. Prog. Rep.
[6] X. Yin et al., RIKEN Accel. Prog. Rep.
[7] H. Arata et al., RIKEN Accel. Prog. Rep.
[8] X. Yin et al., RIKEN Accel. Prog. Rep.
Time Projection Chambers (TPCs) and silicon (Si) semiconductor detectors are useful to examine residual nuclei in nuclear reaction.
We developed MAIKo and MAIKo+, which are TPC-based active target systems [1]. They enable tracking of low-energy charged particles over a large solid angle by using gas as both the detection medium and target. We utilize them to study triple-alpha reaction, which is one of the most important in nucleosynthesis in the universe. We inject a neutron beam into the MAIKo(+) active targets filled with a detection gas containing carbon, and measure 3 alpha particles emitted from excited states of residual carbon nuclei. A test measurement was conducted at the OKTAVIAN neutron beam facility in Osaka University, and it showed significant potential to measure residual nuclei in nuclear reactions [2].
We also developed a Si detector array SAKRA to detect decay particles from residual nuclei. It has particle-identification capabilities via pulse shape analysis. We demonstrated that SAKRA is capable to distinguish protons from alpha particles at E > 2 MeV and alpha particles from carbon nuclei at E > 5 MeV, and useful to examine decay processes of residual nuclei and to clarify their internal structures. We employed SAKRA to search for alpha cluster states in
In this talk, we will report the performance of MAIKo(+) and SAKRA, and present their application in our recent experimental works.
References
[1]. T. Furuno, T. Kawabata
[2]. T. Furuno
[3]. Y. Fujikawa, T. Kawabata