Conceptual study of Post Irradiation Examination (PIE) Facility at J-PARC

Saito, Shigeru; Meigo, Shinichiro; Makimura, Shunsuke*; Hirano, Yukinori*; Tsutsumi, Kazuyoshi*; Maekawa, Fujio

JAEA-Technology 2023-025, 48 Pages, 2024/03

JAEA-Technology-2023-025.pdf:3.11MB

JAEA has been developing Accelerator-Driven Systems (ADS) for research and development of nuclear transmutation using accelerators in order to reduce the volume and hazardousness of high-level radioactive waste generated by nuclear power plants. In order to prepare the material irradiation database necessary for the design of ADS and to study the irradiation effects in Lead-Bismuth Eutectic (LBE) alloys, a proton irradiation facility is under consideration at J-PARC. In this proton irradiation facility, 250 kW proton beams will be injected into the LBE spallation target, and irradiation tests under LBE flow will be performed for candidate structural materials for ADS. Furthermore, semiconductor soft-error tests, medical RI production, and proton beam applications will be performed. Among these, Post Irradiation Examination (PIE) of irradiated samples and RI separation and purification will be carried out in the PIE facility to be constructed near the proton irradiation facility. In this PIE facility, PIE of the equipment and samples irradiated in other facilities in J-PARC will also be performed. This report describes the conceptual study of the PIE facility, including the items to be tested, the test flow, the facilities, the test equipment, etc., and the proposed layout of the facility.

Studying the impact of deuteron non-elastic breakup on Zr + d reaction cross sections measured at 28 MeV/nucleon

Chillery, T.*; Hwang, J.*; Dozono, Masanori*; Imai, Nobuaki*; Michimasa, Shinichiro*; Sumikama, Toshiyuki*; Chiga, Nobuyuki*; Ota, Shinsuke*; Nakayama, Shinsuke; 49 of others*

Progress of Theoretical and Experimental Physics (Internet), 2023(12), p.121D01_1 - 121D01_11, 2023/12

https://doi.org/10.1093/ptep/ptad139

The deuteron is a loosely bound system which can easily break up into its constituent proton and neutron whilst in the presence of Coulomb and nuclear fields. Previous experimental studies have shown that this breakup process has a significant impact on residual nucleus production from deuteron bombardment in the high energy range of 50 - 210 MeV/nucleon. However, there remains a lack of cross-section data at energies below 50 MeV/nucleon. The current study determined Zr + d reaction cross sections under inverse kinematics at approximately 28 MeV/nucleon using the BigRIPS separator, OEDO beamline, and SHARAQ spectrometer. Cross sections from this research were compared with previous measurements and theoretical calculations. The experimental results show a large enhancement of the production cross sections of residual nuclei, especially those produced from a small number of particle emissions, compared to the proton-induced reaction data at similar bombarding energy. The DEURACS calculation, which quantitatively takes deuteron-breakup effects into account, reproduces the data well. As a long-lived fission product, Zr remains a challenge for nuclear waste disposal and treatment. This study's low-energy data may assist future consideration of nuclear-waste treatment facilities, where Zr + d may feasibly transmute the waste into short-lived/stable nuclei.

Comparison of Ichimura-Austern-Vincent and Glauber models for the deuteron-induced inclusive breakup reaction in light and medium-mass nuclei

Liu, H.*; Nakayama, Shinsuke; Lei, J.*; Ren, Z.*

Physical Review C, 108(1), p.014617_1 - 014617_8, 2023/07

https://doi.org/10.1103/PhysRevC.108.014617

In this paper, we study deuteron-induced inclusive breakup reaction and explore the and reactions for light and medium mass nuclei. Using the models of Ichimura, Austern, and Vincent and Glauber, we scrutinize the double differential cross-section of nonelastic breakup and compare the results for various reaction systems. Our findings indicate that the Glauber model, combined with a quantum -matrix, produces remarkable results in the deuteron-induced inclusive breakup reaction. While both models are proficient in predicting the outcomes of light and medium mass nuclei, the reaction showcases higher consistency than the reaction. Nevertheless, there are still significant discrepancies between experimental and theoretical cross-sections that require further investigation and analysis. This study opens up a new realm of possibilities for future research in the field.

Deuteron and alpha sub-libraries of JENDL-5

Nakayama, Shinsuke; Iwamoto, Osamu; Sublet, J.-Ch.*

EPJ Web of Conferences, 284, p.14011_1 - 14011_4, 2023/05

https://doi.org/10.1051/epjconf/202328414011

JENDL-5, the latest version of the Japanese evaluated nuclear data library, includes several sub-libraries to contribute to various applications. In this paper, we outline the evaluation and validation of the deuteron reaction sub-library developed mainly for the design of accelerator-based neutron sources and the alpha-particle reaction sub-library developed mainly for use in the back-end field. As for the deuteron sub-library, the data for Li, Be, and C from JENDL/DEU-2020 were partially modified and adopted. The data up to 200 MeV for Al, Cu, and Nb, which are important as accelerator structural materials, were newly evaluated based on the calculations with the DEURACS code. As for the alpha-particle sub-library, the data up to 15 MeV for 18 light nuclides from Li to Si isotopes were evaluated based on the calculations with the CCONE code, and then only the neutron production cross sections were replaced with the data of JENDL/AN-2005. Validation on neutron yield by Monte Carlo transport simulations was performed for both sub-libraries. As a result, it was confirmed that the simulations based on the sub-libraries showed good agreement with experimental data.

Paper award of Atomic Energy Society of Japan in 2021; JENDL/DEU-2020: deuteron nuclear data library for design studies of accelerator-based neutron sources

Nakayama, Shinsuke

Kaku Deta Nyusu (Internet), (133), p.88 - 99, 2022/10

http://www.aesj.or.jp/~ndd/ndnews/No133.html

The content of the paper that received the Paper Award of Atomic Energy Society of Japan in 2021 is outlined. Although the use of deuteron accelerator-based neutron sources has been proposed in various fields, deuteron nuclear database accurate enough to be applied to the design study of such neutron sources had not been developed. Under these situations, we had developed a deuteron nuclear database, JENDL/DEU-2020. It contains evaluated deuteron nuclear data for light nuclei (Li, Be, C), which are candidates for deuteron beam irradiation targets of the neutron sources. Evaluation of JENDL/DEU-2020 was performed by using the code system DEURACS with further modifications. In order to validate the accuracy of the database, simulations using the particle transport code were performed under various conditions with different target nuclides and incident deuteron energies, and the results were compared with the available experimental data. As a result, it was found that JENDL/DEU-2020 significantly improves the prediction accuracy of experimental data under a wider range of conditions than other nuclear reaction databases or the nuclear reaction models implemented in transport calculation codes.

Beam emittance growth due to the strong space-charge field at low energy of a high-intensity ion linac and its mitigation using an octupole magnetic field

Chimura, Motoki; Harada, Hiroyuki; Kinsho, Michikazu

Progress of Theoretical and Experimental Physics (Internet), 2022(6), p.063G01_1 - 063G01_26, 2022/06

https://doi.org/10.1093/ptep/ptac077

In the low-energy region of a high-intensity ion linac, a strong space-charge field causes a rapid beam emittance growth over a short distance of only few meters. The beam emittance growth leads to a beam loss and the machine activation raising a serious issue for regular maintenance of the accelerator component and beam power ramp up. In this work, we studied the mechanism of beam emittance growth due to the space-charge field based on three-dimensional particle-tracking simulation and theoretical considerations. Numerical simulations done for the high-intensity linac at J-PARC shows that the nonlinear terms in the space-charge field directly cause a beam emittance growth and beam halo formation. Then, we also propose a method to mitigate the beam emittance growth by using an octupole magnetic field, which arises as one of the nonlinear terms in the space-charge field. By applying this method in the simulation, we have succeeded mitigating the beam emittance growth.

Theoretical study of deuteron-induced reactions in the nuclear data field

Nakayama, Shinsuke; Iwamoto, Osamu; Watanabe, Yukinobu*; Ogata, Kazuyuki*

Few-Body Systems, 63(1), p.4_1 - 4_6, 2022/03

https://doi.org/10.1007/s00601-021-01712-2

Intensive neutron sources using deuteron accelerators have been proposed for not only science and engineering fields but also medical applications. For the engineering design of such facilities, accurate and comprehensive nuclear data of deuteron-induced reactions are indispensable. However, it is difficult to meet the requirement by employing experimental data alone. Thus, theoretical model calculations play a key role in completing the necessary nuclear data by interpolation and extrapolation of experimental data. Under the above situations, we have been developing a code system dedicated for deuteron-induced reactions, called DEURACS. In the present work, calculations using DEURACS are compared with available experimental data and validation of the present modelling in DEURACS is discussed. Moreover, the importance of consideration of the breakup processes for accurate prediction of deuteron-induced reactions is also presented.

Measurement of nuclide production cross sections for proton-induced reactions on Mn and Co at 1.3, 2.2, and 3.0 GeV

Takeshita, Hayato*; Meigo, Shinichiro; Matsuda, Hiroki*; Iwamoto, Hiroki; Nakano, Keita; Watanabe, Yukinobu*; Maekawa, Fujio

Nuclear Instruments and Methods in Physics Research B, 511, p.30 - 41, 2022/01

https://doi.org/10.1016/j.nimb.2021.10.016

Nuclide production cross sections for proton-induced reactions on Mn and Co at incident energies of 1.3, 2.2, and 3.0 GeV were measured by the activation method at the J-PARC. In total, 143 production cross sections of reaction products were obtained. Among them, the cross sections of Mn(p,X)S and Mn(p,X)Ar were measured for the first time. The stable proton beam and well established beam monitoring system contributed to the reduction of the systematic uncertainties to typically less than 5%, which was better than those of the previous data. To examine the prediction capabilities of spallation reaction models and evaluated data library, the measured data were compared with the spallation reaction models in PHITS (INCL4.6/GEM, etc.), INCL++/ABLA07, and the JENDL/HE-2007 library. The comparison of the mean square deviation factors indicated that both INCL4.6/GEM and JENDL/HE-2007 showed better agreement with the measured data than the others.

Performance of the next-generation LLRF control system for the J-PARC RCS

Tamura, Fumihiko; Sugiyama, Yasuyuki*; Yoshii, Masahito*; Yamamoto, Masanobu; Okita, Hidefumi; Omori, Chihiro*; Nomura, Masahiro; Shimada, Taihei; Hasegawa, Katsushi*; Hara, Keigo*; et al.

Proceedings of 18th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.170 - 174, 2021/10

https://www.pasj.jp/web_publish/pasj2021/proceedings/PDF/WEOB/WEOB08.pdf

A stable and precise LLRF (Low Level RF) control system is indispensable for acceleration of high intensity proton beam in the J-PARC RCS. The original LLRF control system had been operated without major problems for more than ten years since the start of operation of the RCS, while maintenance of the system became difficult due to the obsolesce of the old FPGAs in the modules. We developed and installed the next-generation LLRF control system based on MTCA.4. The key function of the system is the multiharmonic vector rf voltage control feedback. We describe the system overview and the commissioning results. The performance of the beam loading compensation is significantly improved.

Development of laser system for laser stripping injection

Harada, Hiroyuki; Saha, P. K.; Yoneda, Hitoki*; Michine, Yurina*; Fuchi, Aoi*; Sato, Atsushi*; Kinsho, Michikazu

JPS Conference Proceedings (Internet), 33, p.011026_1 - 011026_6, 2021/03

https://doi.org/10.7566/JPSCP.33.011026

The charge-exchange multi-turn injection by using a carbon stripper foil is adopted in high-intensity proton ring accelerators worldwide. It is a beneficial method to compress the pulsed proton beam with high intensity but there are serious issues for high intensity. First issue is a short lifetime of the foil by deformation or breaking itself. Another issue is high radiation dose corresponding to the scattered particles on the foil. Therefore, a non-destructive stripping injection method is required for higher intensity proton beam. We newly propose a non-destructive method of H stripping by using only laser. The new method is called "laser stripping injection". To establish our method, we are preparing for a POP (Proof-of-Principle) experiment of 400 MeV H- stripping to proton at J-PARC. In our presentation we will present the current status of laser system development for laser stripping injection at J-PARC.