Symposium on Nuclear Data
2020
Thursday, 26 November 2020 - Friday, 27 November 2020
RIKEN Wako Campus

Book of Abstracts

iiContents
Nuclear Data Activities in Nishina Center . . . . . . . . . . . . . . . . . . . . . . . . . .

1

Proposal of 1 A class deuteron single cell linac . . . . . . . . . . . . . . . . . . . . . . . .

1Development of energy-degraded RI beam and expansion of nuclear reaction studies . .

1

Nuclear spectroscopy at KISS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1

Fission experiment with Es at JAEA tandem accelerator facility . . . . . . . . . . . . . .

1

Theoretical analysis of deuteron-induced reactions and development of deuteron nuclear
database . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1

Nuclear data study for Accelerator Driven System at J-PARC . . . . . . . . . . . . . . . .

2

Production and Applications of Radioisotopes at RIKEN RI Beam Factory - Search for New
Elements through Diagnosis and Therapy of Cancer - . . . . . . . . . . . . . . . . . .

2

Measurements of production cross sections of medical radioisotopes via charged-particle
induced reactions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2Development of Radioisotopes Production Method by Accelerator-based Neutron: Activity
at Kyushu University 2020 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2

Deep Learning for Basic Science . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2

Nuclear data generation using machine learning . . . . . . . . . . . . . . . . . . . . . . .

2

Data-driven approaches for nuclear shell-model calculations . . . . . . . . . . . . . . . .

3

Exploration of automated data processing for mass production of nuclear data at RIBF .

3

Unified description of the fission probability for highly excited nuclei . . . . . . . . . . .

3Isotope production in spallation reaction of 93Zr and 93Nb induced by proton and deuteron. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3Introduction to Nuclear Reactor Theory . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3Roles and current status of reactor physics experiment in research reactors . . . . . . . .

3Opening/Welcome . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

4

Closing Remarks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

4iii

Detection of Gamma Ray from Sort-Lived Fission Products at KUCA and KURNS-LINAC

4

Evaluation of Neutron Nuclear Data on Cobalt-59 for JENDL-5 . . . . . . . . . . . . . . .

5

Nuclear data generation using machine learning . . . . . . . . . . . . . . . . . . . . . . .

5Theoretical analysis of deuteron-induced reactions and development of deuteron nuclear
database . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

5

Experimental plan for displacement damage cross sections using 120-GeV protons at FNAL
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6

Theoritical analysis of the fission process by 258 Md . . . . . . . . . . . . . . . . . . . . .

7

Unified description of the fission probability for highly excited nuclei . . . . . . . . . . .

7

Nuclear spectroscopy at KISS / KISS での核分光実験 . . . . . . . . . . . . . . . . . . . .

8

SCALE6.2 ORIGEN library produced from JENDL/AD-2017 . . . . . . . . . . . . . . . . .

8

Nondestructive Determination of Water Content in Concrete Using Am-Be Neutron Source- Experimental Verification - . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

9Development of Absolute Epi-thermal and Fast Neutron Flux Intensity Detectors for BNCT
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

9Study on characteristics of neutron and γ-ray fields at compact neutron source RANS-II
facility by simulation by the PHITS code . . . . . . . . . . . . . . . . . . . . . . . . . 10
Neutron Filtering System for Fast Neutron Cross-Section Measurement at ANNRI . . . . 11
The origin of correlation between mass and angle in quasi-fission . . . . . . . . . . . . . 12
Isotope production in spallation reaction of 93Zr and 93Nb induced by proton and deuteron/ 93Zr 及び 93Nb に対する陽子・重陽子入射核破砕反応からの同位体生成 . . . 12
Experimental program of nuclear data for accelerator-driven nuclear transmutation systemusing FFAG accelerator –First subprogram: spallation neutron measurement . . . . . 13
Estimation of Flux and Residual Radioactivity for the COMET Phase-I Experiment . . . . 13
Neutron emission during fission process by dynamical model/ . . . . . . . . . . . . . . . 14
Production and Applications of Radioisotopes at RIKEN RI Beam Factory - Search for New
Elements through Diagnosis and Therapy of Cancer - . . . . . . . . . . . . . . . . . . 15
Optimization of Activation Detector for Benchmark Experiment of Large-angle Elastic Scattering Reaction Cross Section by 14MeV Neutrons . . . . . . . . . . . . . . . . . . . . 15
Production cross sections of 175Hf in the natLu(p,xn) and natLu(d,xn) reactions . . . . . 16
Introduction to Nuclear Reactor Theory . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Development of Evaluation Method of Uncertainty of Radioactivity by Propagating Nuclear Data Covariance for Clearance Verification in Decommissioning of Nuclear Power
Plants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17iv

Development of a neutron detector for nuclear data measurement using high-intensity neutron beam . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Study of the fission path energy of U-236 using microscopic mean-field model . . . . . . 18
Roles and Current Status on Reactor Physics Experiment in Research Reactors . . . . . . 19
The fission fragments of neutron-rich nuclei by the Langevin method toward application
to r-process calculations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Comparison of photon spectra emitted from fuel debris using different decay data libraries. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Nuclide production cross sections of natLu target irradiated with 0.4-, 1.3-, 2.2-, 3.0-GeV
protons . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
A New Method to Reduce Systematic Uncertainties of Capture Cross Section Measurement
Using a Sample Rotation System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Measurement of neutron total cross sections of Sn-Pb alloys in solid and liquid states . . 22
Comparison of double-differential cross sections between JENDL/PD-2016.1 and experimental data for photo-neutron production of medium-heavy nuclei at 16.6 MeV . . . 23
Nuclear data study for Accelerator Driven System at J-PARC . . . . . . . . . . . . . . . . 23
Development of Radioisotopes Production Method by Accelerator-based Neutron: Activity
at Kyushu University 2020 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Measurements of production cross sections of medical radioisotopes via charged-particle
induced reactions / 荷電粒子入射反応による医療用 RI 生成断面積測定実験 . . . 24
Research for nuclear transmutation of high-radiotoxic nuclide 90 Sr via proton- and deuteroninduced reactions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Theoretical evaluation of non-resonant background strength in binary breakup reaction

25

Proposal of 1 A class deuteron single cell linac / 大強度重陽子加速器 ImPACT2017 の提案 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Conference Photo . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26v

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Facility / 1

Nuclear Data Activities in Nishina Center
Author: Hiroyoshi Sakurai1
1

RIKEN Nishina Center for Accelerator-Based Science

Corresponding Author: sakurai@ribf.riken.jp

Nuclear Data Activities in Nishina Center

Facility / 2

Proposal of 1 A class deuteron single cell linac

NuclearPhysics2 / 3

Development of energy-degraded RI beam and expansion of nuclear reaction studies
Development of energy-degraded RI beam and expansion of nuclear reaction studies

NuclearPhysics1 / 4

Nuclear spectroscopy at KISS
Nuclear spectroscopy at KISS

NuclearPhysics1 / 5

Fission experiment with Es at JAEA tandem accelerator facility

NuclearPhysics2 / 6

Theoretical analysis of deuteron-induced reactions and development of deuteron nuclear database
Theoretical analysis of deuteron-induced reactions and development of deuteron nuclear database

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Facility / 7

Nuclear data study for Accelerator Driven System at J-PARC
Nuclear data study for Accelerator Driven System at J-PARC

NuclearMedicine / 8

Production and Applications of Radioisotopes at RIKEN RI Beam
Factory - Search for New Elements through Diagnosis and Therapy of Cancer Production and Applications of Radioisotopes at RIKEN RI Beam Factory - Search for New Elements
through Diagnosis and Therapy of Cancer -NuclearMedicine / 9

Measurements of production cross sections of medical radioisotopes via charged-particle induced reactions
Measurements of production cross sections of medical radioisotopes via charged-particle induced
reactions

NuclearMedicine / 10

Development of Radioisotopes Production Method by Acceleratorbased Neutron: Activity at Kyushu University 2020
Development of Radioisotopes Production Method by Accelerator-based Neutron: Activity at Kyushu
University 2020

DeepLearning / 11

Deep Learning for Basic Science
Deep Learning for Basic Science

DeepLearning / 12

Nuclear data generation using machine learning
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Nuclear data generation using machine learning

DeepLearning / 13

Data-driven approaches for nuclear shell-model calculations
Data-driven approaches for nuclear shell-model calculations

DeepLearning / 14

Exploration of automated data processing for mass production of
nuclear data at RIBF
Exploration of automated data processing for mass production of nuclear data at RIBF

NuclearPhysics1 / 15

Unified description of the fission probability for highly excitednuclei
Unified description of the fission probability for highly excited nuclei

NuclearPhysics2 / 16

Isotope production in spallation reaction of 93Zr and 93Nb induced by proton and deuteron
Isotope production in spallation reaction of 93Zr and 93Nb induced by proton and deuteron

Tutorial / 17

Introduction to Nuclear Reactor Theory

Tutorial / 18

Roles and current status of reactor physics experiment in research
reactors
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Roles and current status of reactor physics experiment in research reactors

19

Opening/Welcome

20

Closing Remarks

Poster / 23

Detection of Gamma Ray from Sort-Lived Fission Products at KUCA
and KURNS-LINAC
Author: yasushi nauchi 1
Co-authors: Junichi Hori 2 ; Tadafumi Sano 3 ; Yoshiyuki Takahashi 2 ; Koji Kusumi 1 ; Hironobu Unesaki 4
1

Central Research Institute of Electric Power Industry

2

Institute for Integrated Radiation and Nuclear Science, Kyoto University

3

Kindai University

4

Institute for Integrated Radiation and Nuclear Science, Kyoto University

Quantification of radioactivity of fission products (FP) is very important for assessment of decay
heat after shutdown of a core, etc. For such assessments, comprehensive data sets of fission yieldand decay chain, such as JENDL/FPY&FPD-2011, have been developed. However, validation of eachnuclide in such data sets has still been cumbersome. In this work, two detection techniques of FPs
are studied to give data for such validation.
In order to characterize reactions occurred in nuclear fuel, gamma ray spectroscopy was conducted
at Kyoto university critical facility assembly (KUCA). At KUCA, uranium (U)fuel of 93 wt% 235U
enrichment was loaded in C-core. They were moderated and shielded by light water. The core
power during the critical operation was 4.6 mW. Outside the tank of the core, a HP-Ge detector of
30 % relative efficiency was set and the gamma ray was measured. As the results, peak spectra offission products such as 90, 95, 97Y, 90,90m,91Rb, 87,88Br, 136Te, etc. were detected although they
were overwrapped by prompt gamma ray components. Due to the prompt components, the relative
statistical accuracy was from 2 to 20 %. Thanks to the measurements during the critical operation,
gamma rays of half-life shorter than 4 s was achieved.
Contrarily, 238U(n,g) gamma ray spectroscopy was conducted with the same HP-Ge for neutrons ofthermal and resonance energy at the KU-LINAC-pulsed neutron source facility. The time of flight(TOF) of neutron was measured associated with beam pulse to identify the incident neutron energy.
The repetition rate of the pulse was 50 Hz. In the TOF spectrum after the so called “thermal neutronpeak”, time-background region was identified. The gamma ray in the region out of phase of thebeam pulse was considered emitted by decay of radioactive material of which half-life is longer than
20 ms. The measured peak structure was found fairly resemble to that of measured at KUCA.
The detection efficiency of the gamma rays at KUCA was calculated with MCNP-5. That at LINAC
was experimentally determined. With the measured count rate and the efficiency, the gamma ray
emission rate was deduced and compared against that calculated based on JENDL/FPY&FPD-2011.
The ratio of the measured to the calculated value against each gamma ray by the two experiments
show fairly resemble trend. That indicates the both experiments are promising to give reference datafor validation of FP yield and decay data sets such as JENDL/FPY&FPD-2011.
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Poster / 24

Evaluation of Neutron Nuclear Data on Cobalt-59 for JENDL-5
Author: Iwamoto Nobuyuki1
1

JAEA

Cobalt (Co) is one of the structural materials in nuclear and accelerator facilities. It is contained incarbon steel and concrete as well as SUS304. 59 Co is only stable isotope of Cobalt. The nuclear dataof 59 Co are considered to be important specifically for radioactivity estimation of 58,60 Co related
to decommissioning of the facilities. JENDL-4.0 includes the nuclear data of 59 Co, which based theevaluation in 1988. Major revision was carried out at the JENDL-3.3 evaluation in 2001, followed by
the covariance estimation in 2002. After the release of JENDL-3.3, many measured data for capture,(n,2n), (n,p), and (n,α) reactions have been published. Therefore, the reconsideration of nuclear data
is required for JENDL-5.
The evaluation of 59 Co was divided into three energy regions: resolved resonance region, unresolved
resonance region, and fast neutron energy region. In the resolved resonance region, the resonanceparameters and scattering radius were taken from de Saussure et al. (1992). In the unresolved resonance region, the data of thick sample of de Saussure et al. were adopted, supplemented with thedata of thin sample for large resonances. In the fast neutron energy region, the nuclear reaction
model code CCONE was used to calculate cross sections, angular distributions and double differential cross sections. The evaluation was performed based on many types of measured data. The
obtained results are in good agreement with the measured data and will be shown in the poster
presentation.

DeepLearning / 25

Nuclear data generation using machine learning
Author: Hiroki Iwamoto1
1

Japan Atomic Energy Agency

Corresponding Author: iwamoto.hiroki@jaea.go.jp

We have developed a method to generate nuclear data using Gaussian process regression (GPR) [1],which is one of the machine learning techniques. This method generates nuclear data by treating
measured data as the training data in machine learning. GPR is based on nonparametric Bayesianinference, the generated nuclear data are expressed as a predictive distribution including uncertainty
information. In this presentation, the basics of the Gaussian process model, some examples of theapplication to nuclear data generation, and other related topics will be presented.
[1] H. Iwamoto, “Generation of nuclear data using Gaussian process regression”, Journal of Nuclear
Science and Technology, 50:8, 932-938 (2020).

NuclearPhysics2 / 26

Theoretical analysis of deuteron-induced reactions and development of deuteron nuclear database
Author: Shinsuke Nakayama1
1

Japan Atomic Energy Agency

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Corresponding Author: nakayama.shinsuke@jaea.go.jp

Since deuteron is a weakly bound system consisting of a proton and a neutron, it easily breaks up
and emits a neutron through interaction with a target nucleus. Utilizing this property, intensive neutron sources using deuteron accelerators have been proposed for not only science and engineering
fields but also medical applications. For design studies of such facilities, accurate and comprehensive
nuclear data of deuteron-induced reactions are indispensable.
Toward evaluation of deuteron nuclear data, we have developed a code system dedicated for deuteroninduced reactions, called DEURACS. In DEURACS, breakup processes of incident deuteron are taken
into account. DEURACS was so far successfully applied to analyses of production of nucleons, composite particles up to A = 4, and residual nuclei. In this talk, we will present the results of theseanalyses and discuss how important it is to consider the breakup processes for accurate predictionof deuteron-induced reactions.
Moreover, we have recently developed JENDL/DEU-2020, a deuteron nuclear database for Li-6,7,
Be-9, and C-12,13 up to 200 MeV. DEURACS was employed for evaluation of JENDL/DEU-2020. Validation of JENDL/DEU-2020 was carried out by simulation with the Monte Carlo transport codes.
As a result, the simulation using JENDL/DEU-2020 reproduced the measured thick-target neutron
yields better than both simulations using the deuteron sub-library of TENDL and the reaction models
implemented in the PHITS code. These validation results will also be presented.

Poster / 27

Experimental plan for displacement damage cross sections using
120-GeV protons at FNAL
Authors: Yosuke Iwamoto1 ; Makoto Yoshida 2 ; Shin-ichiro Meigo 3 ; Keita Nakano4 ; Shin-ichiro Abe5 ; Taku Ishida2 ;Atsushi Yabuuchi6 ; Atsushi Kinomura6 ; Toshimasa Yoshiie6 ; Katsuya Yonehara7 ; T. Spina7 ; K. Ammigan7 ; N. Mokhov7

1

Nuclear Science and Engineering Center, Japan Atomic Energy Agency (JAEA)

2

J-PARC Center, High Energy Accelerator Research Organization (KEK) / 高エネルギー加速器研究機構 J-PARC
センター

3

J-PARC Center, Japan Atomic Energy Agency (JAEA) / 日本原子力研究開発機構 J-PARC センター

4

J-PARC Center, Japan Atomic Energy Agency (JAEA) / J-PARC Center, Japan Atomic Energy Agency (JAEA) / 日
本原子力研究開発機構 J-PARC センター

5

Nuclear Science and Engineering Center, Japan Atomic Energy Agency (JAEA) / 日本原子力研究開発機構原子力基礎工学研究センター

6

Institute for Integrated Radiation and Nuclear Science, Kyoto University / 京都大学複合原子力科学研究所

7

Fermi National Accelerator Laboratory (FNAL) / 米国フェルミ国立加速器研究所

Corresponding Author: iwamoto.yosuke@jaea.go.jp

To predict the operating lifetime of materials in high-energy radiation environments at accelerator
facilities, Monte Carlo codes such as PHITS, MARS, and FLUKA are used to calculate the numberof displacements per atom (dpa) related to the number of Frenkel pairs. The Norgertt–Robinson–
Torrens (NRT) model has been widely used to predict the number of “initial”Frenkel pairs (NRT-dpa).
For more accurate estimation of the actual damage production, athermal-recombination-correcteddisplacement damage (arc-dpa) was proposed, recently. For the validation of codes, it is necessary
to measure displacement cross-sections of metals in relation to changes in electrical resistivity at
cryogenic temperature (around 4 K) where the recombination of Frenkel pairs by thermal motion iswell suppressed. The comparison between the experimental data and calculated results for proton
irradiation with energies from 0.1 to 30 GeV indicates that the arc-dpa results are good agreementswith the experimental data and the NRT-dpa results are larger than the data by a factor of aroundthree.
In this presentation, we introduce our experimental plan for displacement cross sections with 120GeV protons at Fermilab Test Beam Facility (FTBF) in Fermi National Accelerator Laboratory (FNAL).
Experiments will be performed at the M03 beam line high rate tracking area in FTBF for the US fiscal
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year 2022 (October 2021 –September 2022). For the preparation of experiments, we developed thesample assembly with four wire sample of Al, Cu, Nb and W with 250-µm diameter and 4-cm length.
Annealing under vacuum condition (~10−4 Pa) was performed by heating an Al sample at 840 K for
30 minutes, a Cu sample at 1289 K for 30 minutes, a Nb sample at 1923 K for 15 minutes, and a W
sample at 2473 K for 15 minutes, respectively. The sample assembly will be maintained at around4 K by using a Gifford–McMahon (GM) cryocooler in a vacuum chamber. Then, changes in theelectrical resistivity of samples will be obtained under 120-GeV proton irradiation. Recovery of theaccumulated defects through isochronal annealing, which is related to the defect concentration in
the sample, will also be measured after the cryogenic irradiation.
This work was supported by JSPS KAKENHI Grant Number JP19H02652.

Poster / 28

Theoritical analysis of the fission process by 258 Md
Author: Shoma Ishizaki1
Co-authors: Mizuki/瑞貴 Okubayashi/奥林 2 ; Yoshihiro/嘉浩 Aritomo/有友 2 ; Katsuhisa/勝久 Nishio/西尾 3 ;Kentaro/健太郎 Hirose/廣瀬 3
1

Kindai University

2

Kindai University/近畿大学

3

JAEA/日本原子力研究開発機構

It has been shown that fission has multiple modes, characterized by mass asymmetric fission andmass symmetric fission[1]. In neutron-rich heavy element region,it is argued that several fission
modes coexist, with a significant change of their yields in accordance with the number of neutronscontained in the fissionig nucleus. A typical example is found in the isotope dependence of fission
for fermium isotopes.
For Fm, the dominant mode transitions from the asymmetric splitting for 257 Fm to the symmetricfor 258 Fm[2].
This transitions was interpreted as due to the lowering of the fission barrier for symmetric fission,and the becoming energy advantage fission path of symmetric fission then asymmetric fission.
It’s important to know of the potential energy surface structure and nuclear’s deformation process
to understand fission mechanism in neutron-rich heavy element region[3].
258Md, which is the target of this work, is located near the boundary line where the transition frommass asymmetric fission to mass symmetric fission is expected to occur, and in recent years, theJapan Atomic Energy Agency has obtained the world’s first fission data. As a result of data analysis,
it shown that the mode of mass symmetric fission (superlong-mode) and the mode of asymmetricfission (standard-mode) coexist.
In this work, we compared the calculation using the fluctuation dissipation model(Langevin calculation)[4] with the experimental data, and considered the characteristics of the fission mode shownby the experimental data.
Reference[1] U. Brosa, S. Grossmann, and A. Muller, Phys. Rep. 197,167 (1990).
[2] D.C. Hoffman et al., Phys. Rev. C, 21, 1980 (637)[3] Y. Miyamoto et al., Phys. Rev. C, 99, 051601(R) (2019).
[4] S. Tanaka, Y. Aritomo, Y. Miyamoto, K. Hirose, and K. Nishio PRC 100, 064605 (2019).

NuclearPhysics1 / 29

Unified description of the fission probability for highly excitednucleiPage 7

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Authors: Hiroki Iwamoto1 ; Shin-ichiro Meigo2
1

Japan Atomic Energy Agency

2

J-PARC/JAEA

Various spallation reaction models have been developed for the use of neutronic and shielding designof high-energy accelerator facilities such as J-PARC and ADS. However, their complicated theory forthe de-excitation process has made improving their prediction accuracy difficult. In particular, it has
been pointed out that the conventional models underestimate the yield of the spallation products
produced from the fission reaction. This work has thus aimed to model the probability was describedusing a simpler, systematic expression, and then confirmed to predict fission cross sections for various incident energies and target nuclei with improved accuracy [1]. In this presentation, we will
present a description of our model and research results.
[1] H. Iwamoto, S. Meigo, “Unified description of the fission probability for highly excited nuclei”,
Journal of Nuclear Science and Technology, 56:2, 160-171 (2020).

NuclearPhysics1 / 30

Nuclear spectroscopy at KISS / KISS での核分光実験
Author: Yoshikazu/賀一 HIRAYAMA/平山1
1

KEK/KEKFor nuclear spectroscopy in the vicinity of N=126 and U-238, we have developed KEK Isotope Separation System (KISS), which is an argon-gas-cell-based laser ion source combined with an on-line isotope separator, installed in the RIKEN Nishina center [1]. The nuclei around N = 126 are produced bymulti-nucleon transfer reactions (MNT) [2] of Xe-136 beam (10.75 MeV/A) impinging upon a Pt-198
target. The KISS facility has a detector station for beta-gamma spectroscopy and a MRTOF systemfor precise mass measurement. By using these devices, we have successfully performed beta-gamma
spectroscopy of Os, Ta [3], and Re isotopes for the half-life measurements and study of beta-decay
schemes, and in-gas-cell laser ionization spectroscopy of Pt, Ir, and Os isotopes for evaluating themagnetic moments and the trend of the charge-radii (deformation parameters).
In the presentation, we will report the present status of KISS, experimental results of nuclear spectroscopy in the heavy region, and future plan of KISS activities.
[1] Y. Hirayama et al., Nucl. Instrum. Methods B 353 (2015) 4.; B 463 (2020) 425.
[2] Y.X. Watanabe et al., Phys. Rev. Lett. 115 (2015) 172503.
[3] P. Walker et al., Phys. Rev. Lett 125 (2020) 192505.

Poster / 31

SCALE6.2 ORIGEN library produced from JENDL/AD-2017
Author: Chikara Konno 1
Co-authors: Mami / 真美 Kochiyama / 河内山 2 ; Hirokazu / 宏一 Hayashi / 林 2
1

Japan Atomic Energy Agency

2

Japan Atomic Energy Agency / 日本原子力研究開発機構

Oak Ridge National Laboratory released the SCALE6.2 code [1] in 2016 (the latest version is SCALE6.2.4).
The ORIGEN code [1] in SCALE6.2 is completely different from the ORIGEN-S code [2] until SCALE6.0
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1) ORIGEN uses one group cross section data generated from a specified neutron spectrum and amultigroup activation library with the COUPLE code [1], not three group cross section data with atypical neutron spectrum.
2) The input format of ORIGEN is easy to use and understand.
3) It is expected that the calculation accuracy improves because ORIGEN uses one group cross section data generated from neutron spectra in all calculation points.
4) The calculation time of ORIGEN including COUPLE is at most about twice of that of ORIGEN-S
even for 200 groups.
We expect that ORIGEN in SCALE6.2 will be mainly used for activation calculations in nuclear facility decommissioning. Thus we produced a SCALE6.2 ORIGEN library from JENDL Activation Cross
Section File for Nuclear Decommissioning 2017 (JENDL/AD-2017) [3] with the AMPX-6 [4] in orderto popularize JENDL/AD-2017 widely. The processing conditions are as follows.
- Temperature : 300 K- Group structure : 200 groups (the same as one of libraries attached in SCALE6.2)- Weight function : Maxwell+1/E+Fission spectrum + 1/E (above 10 MeV)
- Infinite dilution
We tested the SCALE6.2 ORIGEN library of JENDL/AD-2017 with the JPDR decommissioning data[5], which demonstrated the library had no problem.
References[1] ORNL, “SCALE: A Modular Code System for Performing Standardized Computer Analyses forLicensing Evaluation,”ORNL/TM-2005/39 Version 6, Oak Ridge National Laboratory (2009).
[2] (Ed.) W.A. Wieselquist, R.A. Lefebvre, M.A. Jessee, “SCALE Code System,”ORNL/TM-2005/39
Version 6.2.4, Oak Ridge National Laboratory (2020).
[3] https://wwwndc.jaea.go.jp/ftpnd/jendl/jendl-ad-2017.html[4] 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, Oak Ridge National Laboratory (2016).
[5] T. Sukegawa, N. Sasamoto, K. Fujiki, “ACCURACY VERIFICATION FOR CALCULATION OF
INVENTORY IN JPDR DUE TO NEUTRON ACTIVATION,”INDC(JPN)-164, International Atomic
Energy Agency (1993).

Poster / 32

Nondestructive Determination of Water Content in Concrete Using Am-Be Neutron Source - Experimental Verification Author: Yoshihiro Miyaji 1
Co-authors: Isao Murata 2 ; Fuminobu Sato 2 ; Shingo Tamaki 2 ; Sachie Kusaka 2
1

Graduate School of Engineering Osaka University Osaka

2

Graduate School of Engineering Osaka University / 大阪大学大学院工学研究科

A new nondestructive measurement technique has been developed to evaluate the amount of waterin concrete. A concrete wall is irradiated with fast neutrons to activate a gold foil set on the concrete.
By evaluating in advance the relation of the gold activity and water content by calculations, we candetermine the water content in the concrete, the water content of which is not known. In thisstudy, to validate the present technique experiments were performed with concrete samples having
different water contents, which were made from only cement and water. It was confirmed fromthe experiments that water content could be estimated by the present nondestructive measurement
technique though the system is still simple with cement and water. Now we are examining thevalidity for concretes made from cement, water and sand.

Poster / 33
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Development of Absolute Epi-thermal and Fast Neutron Flux Intensity Detectors for BNCT
Author: Kazushi Aoki1
Co-authors: Shingo Tamaki 1 ; Sachie Kusaka 1 ; Fuminobu Sato 1 ; Isao Murata 1
1

Graduate School of Engineering, Osaka Univ.

Corresponding Author: aoki@qr.see.eng.osaka-u.ac.jp

BNCT is a promising cancer therapy which kills tumor cells while suppressing exposure dose tonormal tissues. Normally, the neutron field of BNCT, which is produced by a nuclear reactor or an
accelerator-based neutron source, has an energy distribution spreading within thermal, epi-thermal
and fast neutron regions. Because epi-thermal neutrons are generally used for BNCT, we must measure the epi-thermal neutron flux intensity to evaluate the therapeutic effect and patient’s exposure
dose. In addition, we also have to measure the fast neutron flux intensity to evaluate the exposure
dose that may be harmful to the human body. However, it is quite difficult to measure such intensities directly and accurately because there is no suitable neutron spectrometer and no activationmaterial covering epi-thermal or fast neutrons separately. The objective of this work is hence todevelop new detectors to precisely measure the absolute integral flux intensities of epi-thermal andfast neutrons.
An epi-thermal neutron detector we develop controls its sensitivity by using cadmium and polyethylene. A fast neutron detector controls by using cadmium, B4C and polyethylene. The shape of the
epi-thermal neutron detector is a cube, each side of which is 5.52 cm covered with a cadmium sheet.
However, the epi-thermal neutron detector is a little sensitive to fast neutrons. To clarify the fastneutron contribution, we develop the fast neutron detector. To extract only fast neutrons, the fastneutron detector consists of two sub-detectors, and the fast neutron intensity is estimated by making
difference of the two sub-detectors. The shape of one of them is a cube covered with polyethylene
with a side of 4.4 cm and that of the other is a cube covered with B4C with a side of 4.6 cm. Moderated neutrons are measured by activation reaction of 71Ga (n, γ) 72Ga of a GaN foil positioned at
the center of the detector. Design calculations were carried out by MCNP5.
After fabricating the detectors, in order to test the performance of the epi-thermal and fast neutron
detectors, verification experiments were conducted at KUR, Kyoto University and FNL facility, Tohoku University, respectively.
As the result, the epi-thermal neutron flux intensity could be measured with an error of 3.9 % bycorrecting the high energy neutron contribution with the calculated value. The fast neutron flux
intensity could be measured accurately, that is, the experimental and calculated values agree wellwithin the error range.

Poster / 34

Study on characteristics of neutron and γ-ray fields at compact
neutron source RANS-II facility by simulation by the PHITS code
Author: Kenta SUGIHARA 1
Co-authors: Yujiro IKEDA 2 ; Tomohiro KOBAYASHI 3 ; Kunihiro FUJITA 3 ; Nobuhiro Shigyo 4 ; Kanenobu TANAKA
5; Yoshie OTAKE 3
1

RIKEN Nishina Center, Department of Applied Quantum Physics and Nuclear Engineering, Kyushu University

2

RIKEN Center for Advanced Photonics, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan / 理化学研究所光
量子工学研究センター中性子ビーム技術開発チーム, J-PARC Center, Japan Atomic Energy Agency, 2-4
Shirakata, Tokai-mura, Naka-gun, Ibaraki 319-1195, Japan / 日本原子力研究開発機構 J-PARC センター

3

RIKEN Center for Advanced Photonics, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan / 理化学研究所光
量子工学研究センター中性子ビーム技術開発チーム

4

Department of Applied Quantum Physics and Nuclear Engineering, Kyushu University, Motooka, Nishi-ku, Fukuoka
819-0395, Japan / 九州大学大学院工学研究院エネルギー量子工学部門

5

RIKEN Nishina Center

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RIKEN Accelerator driven compact Neutron Source-II (RANS-II) based on the 7 Li(p, n)7 Be reaction
for neutron production with 2.49 MeV proton beam, has been under beam commissioning to demonstrate specific performance of the system. RIKEN has a prospect of realizing novel non-destructive
neutron inspection for infrastructures with the use of RANS. As prominent characteristics, RANS-II
has the maximum neutron energy of 0.8 MeV, which is lower than that of 5 MeV at RANS based on
the 9 Be(p, n)9 B reaction with 7 MeV proton injection, and gives extremely forward favored angular
distribution with respect to the proton beam direction. Also, it should be emphasized that RANS-II
system is installed in a relatively small space isolated by concrete shield with boron containment.
Accordingly, there should be quite large differences in neutronic performances between RANS-IIand RANS in terms of neutron spectrum and angular distributions. In preparation of experiments at
RANS-II, the simulation of radiation fields for neutron and γ-ray in RANS-II experimental hall playsa critical important role for designing experimental set-up in low background.
Then, we have performed simulations to characterize radiation fields of RANS-II The cross section
libraries implemented in PHITS are utilized in neutron and γ-ray transportations. Several importantconditions of RANS-II modeling are as follows:
・The lithium (Li) target is made by depositing thin Li layer of about 100 µm on a 5 mm thick Cu
substrate cooled by water in the target station.
・The target station with about 90 cm side cubic shape, configures five layers; polyethylene, lead,borated polyethylene, lead and iron, to reduce the radiation leakage.
・There is a hole with a 15 × 15 cm2 cross section in the forward direction.
・The experimental hall has dimensions of 14 × 5.5 × 3.0 m3 surrounded by floor and wall made ofconcrete (partly the borated concrete) and polyethylene ceiling.
As a result, the neutron and γ-ray distribution spreads widely in the experimental hall due to thewide openings in the target station. The scattered radiation could be the major contributor to thebackground of experiments. On the other hand, primary neutrons produced at the target are shielded
reasonably by the target station. To design effective collimators for high quality beam extraction,
we have calculated neutron beam profiles with parameters of collimator diameters and materials. It
is shown that there is an optimized collimator configuration to extract suitable beam.

Poster / 35

Neutron Filtering System for Fast Neutron Cross-Section Measurement at ANNRI
Author: Gerard Rovira Leveroni1
Co-authors: Nobuyuki Iwamoto 1 ; Shunsuke Endo 1 ; Shoji Nakamura 1 ; Atsushi Kimura 1 ; Osamu Iwamoto 1 ;Tatsuya Katabuchi 2 ; Kazushi Terada 1 ; Yu Kodama 2 ; Yuji Shibahara 3 ; Jun-ichi Hori 3 ; Hideto Nakano 2
1

JAEA

2

Tokyo Institute of Technology

3

Kyoto University

The Accurate Neutron-Nucleus Reaction Measurement Instrument (ANNRI) beamline in the Materials and Life Science (MLF) experimental facility of the Japan Proton Accelerator Research Complex(J-PARC) provides the most intense neutron beam available in the world and was carefully designed
to precisely measure neutron-induced reactions using the time-of-flight (TOF) method. Currently,
the J-PARC accelerator is operated in double-bunch mode in which two 0.1 μs wide proton
bunches are shot into a spallation target with a time difference of 0.6 μs. Because of this, events
detected with a specific time-of-flight (TOF) have two different energies as they could have beenoriginated from each of the two different proton pulses. This is particularly important in the continuum
region (keV region) where the cross section can be expressed as a smooth averaged function. In thisregion, it is impossible to separate the contribution from each proton pulse and, hence, this mode
introduces serious ambiguities into the cross-section measurements.
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A neutron filtering system has been designed in order to bypass the double-bunched structure of
the neutron beam as part of the “Study on accuracy improvement of fast-neutron capture reaction
data of long-lived MAs for development of nuclear transmutation systems”project. Filter materials
were introduced into the ANNRI beamline in order to produce quasi-monoenergetic neutron filteredbeams. The materials suitable to be used as filters present sharp minima in the total cross-section
due to the interference between the potential and s-wave resonance scattering. Neutrons havingthat energy can be transmitted through the filters and, therefore, produce a quasi-monoenergetic
beam. Filter assemblies consisting of Fe with a thickness of 20 cm, and Si with thicknesses of 20 cm
and 30 cm of Si were used separately to produce filtered neutron peaks with energies of 24 keV (Fe)and of 54 and 144 keV (Si).
In this study, the characteristics and performance of the neutron filtering system at ANNRI using
Fe and Si determined from both measurements and simulations are presented. The incident neutron flux was analyzed by means of transmission experiments using Li-glass detectors and captureexperiments using a boron sample which was measured with a NaI(Tl) spectrometer. Moreover,simulations using the PHITS code were performed in order to determine the energy distribution of
the integrated filtered peaks and assess the reliability of experimental results. Finally, preliminary
results of the capture cross section of 197 Au are presented using the NaI(Tl) spectrometer alongside
the neutron filtering system.

Poster / 36

The origin of correlation between mass and angle in quasi-fission
Author: Shota Amano1
Co-authors: Yoshihiro Aritomo 1 ; Shoma Ishizaki 2 ; Mizuki Okubayashi 1 ; Seiya Okugawa 2
1

Kindai University

2

Kindai university

Mass-angle distribution (MAD) measurement of heavy and superheavy element fragmentation reactions is one of the powerful tools for investigating the mechanism of fission and fusion process.
MAD shows a strong correlation between mass and angle when the quasi-fission event is dominant.
It has characteristic that appears diagonal correlation as long as the quasi-fission event is dominant.
This diagonal correlation could not be reproduced in previous our model before the introduction of
the parameters.
In this study, we systematically evaluate the uncertainty model parameters contained in our modeland clarify those model parameters to reproduce the diagonal correlation that appears in MAD. Usinga dynamical model based on the fluctuation diffraction theorem that employs Langevin equations,
we calculate the mass angle distribution and mass distribution of the four reaction systems 48Ti +186W, 34S + 232Th, 48Ti + 208Pb, and 28S + 238U, which are dominated by quasi-fission. We wereable to clarify the effects of uncertain model parameters on the mass angle distribution and mass
distribution. In addition, we identified the values of model parameters that can reproduce the correlation between mass and angle. As a result, it found that the balance of tangential friction andmoment of inertia values is important for the correlation between mass and angle.

NuclearPhysics2 / 37

Isotope production in spallation reaction of 93Zr and 93Nb induced by proton and deuteron / 93Zr 及び 93Nb に対する陽子・重陽子入射核破砕反応からの同位体生成
Author: Kieta / 敬太 Nakano / 中野1

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1

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JAEA / JAEA

Nuclear transmutation technology has been attracting attention as a method for treating high-level
radioactive waste. One of the candidates is the spallation reaction using high-energy particles, especially for the nuclides with relatively small neutron-capture cross sections such as long-lived fission
product (LLFP) 93 Zr. The accumulation of nuclear reaction data and the development of nuclear
reaction models based on the data are indispensable for the accurate prediction of the amount of
conversion of 93 Zr to stable nuclides and/or short-lived nuclides and residual long-lived nuclides
after the transmutation. Therefore, under the ImPACT program (Period: 2014 –2018), we have measured isotope-production cross sections in proton- and deuteron-induced spallation reactions on
LLFP 93 Zr and adjacent nuclide 93 Nb at RIKEN RIBF.
In the experiment, a 93 Zr beam at 50 MeV/nucleon and a 93 Nb beam at 113 MeV/nucleon
were produced by inflight-fission of 238 U. These beams were irradiated to secondary targets containing hydrogen and deuterium to induce spallation reactions, and the product yields were analyzed by
ZeroDegree Spectrometer to determine the product cross sections. The results are compared with
the nuclear reaction models.

Poster / 38

Experimental program of nuclear data for accelerator-driven nuclear transmutation system using FFAG accelerator –First subprogram: spallation neutron measurement
Author: Keita Nakano 1
Co-authors: Hiroki Iwamoto 1 ; Shin-ichiro Meigo 2 ; Katsuhisa Nishio 3 ; Yoshihiro Ishi 4 ; Kentaro Hirose 1 ; Yosuke
Iwamoto 1 ; Yasutoshi Kuriyama 4 ; Fujio Maekawa 1 ; Hiroyuki Makii 3 ; Kota Okabe 1 ; Orlandi Riccardo 5 ; Akito
Oizumi 3 ; Daiki Sato 1 ; Fumi Suzaki 1 ; Kazuaki Tsukada 1 ; Tomonori Uesugi 6 ; Hiroshi Yashima 6
1

JAEA

2

J-PARC Center, Japan Atomic Energy Agency (JAEA), Japan

3

JAEA

4

Kyoto University

5

JAEA / JAEA

6

Kyoto University

For accurate prediction of neutronic characteristics for accelerator-driven system (ADS) and a source
term of spallation neutrons for reactor physics experiments for the ADS at Kyoto University Critical
Assembly (KUCA), we have launched an experimental program to measure nuclear data on ADS
using the Fixed Field Alternating Gradient (FFAG) accelerator at Kyoto University (Period: October
2019 –March 2023). This program is composed of two subprograms, focusing on two nuclear reaction
mechanisms, (1) spallation reactions and (2) high-energy fission, for incident proton energies fromseveral tens of MeV to 100 MeV. In the first subprogram, we will measure neutron energy spectra of
double-differential cross-sections (DDXs) and thick-target neutron-yields (TTNYs) for several targets(i.e. Pb, Bi, Fe, etc.); in the second subprogram, fission fragment mass number induced from heavy
targets (i.e. Pb, Bi) will be measured. In this poster session, the present status of the first subprogram
will be presented.

Poster / 39

Estimation of Flux and Residual Radioactivity for the COMET
Phase-I Experiment
Author: Naoki Tokunaga 1

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Co-authors: Nobuhiro Shigyo 1 ; Shunsuke Makimura 2 ; Yoshinori Fukao 2 ; Naoya Kamei 2 ; Makoto Yoshida

3

1

Kyushu University

2

Institute of Particle and Nuclear Studies J-PARC Center Particle and Nuclear Physics Division Hadron Section Tokai
campus / 素粒子原子核研究所Ｊ－ＰＡＲＣセンター素粒子原子核ディビジョンハドロンセクショ
ン東海キャンパス

3

J-PARC Center, High Energy Accelerator Research Organization (KEK) / 高エネルギー加速器研究機構 J-PARC
センター

COherent Muon to Electron Transition (COMET) is an experiment at J-PARC, which will search forcoherent neutrino-less conversion of a muon to an electron in muonic atoms. The experiment will be
carried out in two steps: Phase-I and Phase-II. In the Phase-I experiment, 3.2 kW 8 GeV proton beamirradiates a 70-cm long graphite target to produce negative pions. The negative pions are captured in
the magnetic field and delivered to pion-decay and muon-transport sections. The Phase-I experiment
aims to detect the µ− e conversion events and measure the beam-related background events for thePhase-II experiment. Now, it has been planned that the maintenance by radiation workers would be
conducted after the 150-day operation and the following 180-day cooling. It is necessary to evaluate
the residual radiation dose for the safety of the workers during the maintenance. On this study, we
calculated fluxes of neutron, photon, proton and other charged particles in the beam room during thebeam operation and the residual activity after the cooling time by using Monte Carlo simulation code
PHITS version 3.22 and DCHAIN-PHITS version 3.21. The calculation results show that the designof components around the target and beam dump needs to be improved to reduce the radioactivities
after the cooling time.

Poster / 40

Neutron emission during fission process by dynamical model/
Author: Ryota Yamasaki1
Co-authors: Shoya Tanaka 2 ; Yoshihiro Aritomo 1 ; Katuhisa Nishio 3
1

Kindai University

2

kindai University

3

Advanced Science Research Center, Japan Atomic Energy Agency/日本原子力研究開発機構先端基礎研究センター

Through joint research by the Japan Atomic Energy Agency (JAEA) and Kindai University, it has
become clear that the yield distribution of fission products (fission fragments) changes significantly
depending on the neutrons emitted from the compound nucleus. In the so-called multichance fission(MCF) concept, fission takes place after emitting several neutrons. This revives the shell structure ofa nucleus responsible for mass-asymmetric fission, thus change the fission-fragment mass distribution. The effect of MCF is particularly important to treat high energy fissions, such as ADS system
which transmute long lived minor actinide nucleus by fission. Until now, the calculation was performed by combining the fission model calculation (Langevin equation) and a statistical model usinga code such as GEF [1,2]. However, this method does not introduce neutron emission during the fission process.
In the present work, we have introduced the neutron evaporation during fission process in theLangevin model. For this, a change of potential energy in each neutron evaporation step is treated.
Fission fragment mass distribution of 236−238 U,238−240 Np, and 240−242 Pu were calculated in theinitial excitation energy range of E*=15-55MeV. The results show that the double-peak structure ismaintained even at the highest excitation energies, and successfully reproduced the experimental
data taken at the JAEA tandem facility [3-5].
Reference[1] K, H, Schmidt, B. Jurado, C. Amouroux, and C. Schmitt, Nucl.Data Sheets 131, 107(2016).
[2] S.Tanaka, Y.Aritomo et al., Phys. Rev. C 100, 064605(2019).
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/ Book of Abstracts[3] R. Leguillon, K. Nishio et al., Phys. Lett. B 761, 125(2016).
[4] K. Hirose, K. Nishio et al., Phys. Rev. Lett. 119, 222501(2017).
[5] M. Vermeulen, K. Nishio et al., Phys. Rev. C, in print.

NuclearMedicine / 41

Production and Applications of Radioisotopes at RIKEN RI Beam
Factory - Search for New Elements through Diagnosis and Therapy of Cancer Author: Hiromitsu Haba1
1

Nishina Center for Accelerator-Based Science, RIKENAt RIKEN RI Beam Factory (RIBF), we have been developing production technologies of radioisotopes (RIs) and conducting RI application studies in the fields of physics, chemistry, biology, engineering, medicine, pharmaceutical and environmental sciences [1]. With light- to heavy-ion beams
from the AVF cyclotron, we produce more than 100 RIs from 7Be (atomic number Z = 4) to 262Db (Z= 105). Recently, we often produce 211At in the 209Bi(α,2n)211At reaction for nuclear medicine [2].
RIs of a large number of elements (multitracer) are simultaneously produced from metallic targets
such as natAg, 197Au, and 232Th irradiated with a 135-MeV nucl.–1 14N beam from RIKEN Ring Cyclotron [3]. The multitracer is useful to trace the behavior of many elements simultaneously under an
identical experimental condition. We installed a gas-jet transport system to the GAs-filled Recoil Ion
Separator (GARIS) as a novel technique for superheavy element chemistry [4]. Long-lived isotopes of
261Rfa,b, 262Db, 265Sga,b (Z = 106), and 266Bh (Z = 107) useful for chemistry studies were producedin the heavy-ion induced reactions on a 248Cm target and their decay properties were investigatedin detail using a rotating wheel apparatus for α and spontaneous fission spectrometry [5–8]. Thanks
to the pre-separation of Sg atoms with GARIS, chemical synthesis and gas-chromatographic analysisof the first organometallic compound of SHEs, Sg(CO)6 were conducted under a large international
collaboration lead by the Univ. Mainz and GSI groups [9].
[1] H. Haba et al., in Handbook of Nuclear Chemistry (2nd ed.), edited by A. Vértes, S. Nagy, Z.
Klencsár, R. G. Lovas, and F. Roesch, Vol. 3, Springer, (2010) 1761–1792.
[2] K. Fujiki et al., Chem. Sci. 10 (2019) 1936.
[3] H. Haba et al., Radiochim. Acta 93 (2005) 539.
[4] H. Haba et al., Chem. Lett. 38 (2009) 426.
[5] H. Haba et al., Phys. Rev. C 83 (2011) 034602.
[6] H. Haba et al., Phys. Rev. C 85 (2012) 024611.
[7] H. Haba et al., Phys. Rev. C 89 (2014) 024618.
[8] H. Haba et al., Phys. Rev. C 102 (2020) 024625.
[9] J. Even et al., Science 345 (2014) 1491.

Poster / 42

Optimization of Activation Detector for Benchmark Experimentof Large-angle Elastic Scattering Reaction Cross Section by 14MeV
Neutrons
Author: Takehara Ryohei1
Co-authors: Kazuki Fukui 1 ; Sota Araki 1 ; Shingo Tamaki 2 ; Sachie Kusaka 3 ; Isao Murata 2
1

Graduate school of Engineering, Osaka University

2

Osaka University

3

osaka University

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/ Book of Abstracts<span> The elastic scattering reaction cross section data commonly show smaller in backward angles compared to those of forward angles when the energy of the incident neutron is high. However,in high neutron flux field, such as fusion reactor, the back-scattering reaction cross section is becoming not negligible on the calculation result. Until now, there were differences reported between
experimental and calculated values of neutron benchmark experiments using a DT neutron source,which focused on back-scattering phenomena like a gap streaming experiment. For this problem,the author’s group developed a benchmark method for large-angle scattering cross sections and has
carried out experiments with an iron sample for the last few years. The benchmark method was
successfully established based on the activation of Nb foil having a large activation cross section ataround 14 MeV.
<span>We are now planning to carry out benchmark experiments for other fusion structural
materials such as tungsten, lead, F82H and so on. And in the next step, we aim to consider benchmark experiments for lighter materials like Li, Be, B, C, N and O. In this case, the energy of neutrons
generated by backscattering is low. Especially for Li, being one of the most important materials in
fusion reactor, back-scattering neutrons cannot be captured by Nb foil due to the high thresholdenergy of <sup>93</sup>Nb(n,2n) reaction.
<span>In this study, to solve this problem, we examined possible nuclides having a low activation reaction threshold energy, so that it can react with low energy neutrons generated by thebackscattering of Li, and simultaneously having not too low threshold energy, so that the influenceof room-return neutrons can be eliminated properly. The optimization was achieved by calculating
and comparing the number of counts for all the possible reactions of all the existing stable nuclides
considering appropriate irradiation and measuring times. The activation reaction cross section data
were taken from JENDL/AD-2017.
<span>As a result, we have found that <sup>181</sup>Ta(n,2n) was the most suitable reaction
giving us the largest number of counts in an acceptable short experimental time. Then experiments
were carried out to confirm whether <sup>181</sup>Ta(n,2n)<sup> cross section was consistent
with the nuclear data.

Poster / 43

Production cross sections of 175Hf in the natLu(p,xn) and natLu(d,xn)
reactions
Author: Yukiko Komori1
Co-authors: Hiromitsu Haba 2 ; Masayuki Aikawa 3 ; Moemi Saito 4 ; Sandor Takacs 5 ; Ferenc Ditroi 5
1

RIKEN Nishina Center

2

RIKEN bNishina Center3

Grad. School of Biomed. Sci. and Eng., Hokkaido Univ./北大院医理工4Hokkaido Univ.

5

ATOMKI

A long-lived isotope of Hf, 175Hf (T1/2 = 70 d), is useful for basic studies for rutherfordium (Rf, Z =104). This isotope is producible in no-carrier-added form in the proton- and deuteron-induced reactions on natLu. However, excitation functions of these nuclear reactions have been scarcely studied.
In this work, we measured the excitation functions of the natLu(p,xn)175Hf and natLu(d,xn)175Hf
reactions up to 18-MeV proton and 24-MeV deuteron energies using a stack-foil technique anda γ-ray spectrometry. We performed these experiments at RIKEN and Institute for Nuclear Research (ATOMKI). The target stacks of Ta/Lu/Ti and Lu/Ti foils were irradiated for 2 h with proton or deuteron beams of approximately 180‒240 nA. After the irradiation, each foil was subjectedto γ-ray spectrometry with Ge detectors. We noticed that the half-life of 173Hf is slightly longer
than that adopted in the current nuclear database. Therefore, we measured a precision half-life of
173Hf in a separate experiment. In this work, we could measure the excitation functions of thenatLu(p,xn)173,175Hf and natLu(d,x)173,175Hf, 173,174m,174g,176m,177m,177gLu reactions. Thicktarget yields of 175Hf were also deduced from the measured excitation functions. The yields are 0.47
MBq/µA·h at 17.2-MeV proton and 2.0 MBq/µA·h at 24.0 MeV deuteron. We determined the half-lifeof 173Hf to be 24.176 ± 0.012 h which is 0.58 ± 0.10 h longer than that in the database.
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Tutorial / 44

Introduction to Nuclear Reactor Theory
Author: Tomohiro Endo1
1

Nagoya University

In this tutorial, I would like to briefly introduce the nuclear reactor theory.
Please keep in mind that the whole nuclear fission power plant is a too complicated system, thus
it is not easy to understand the multi-physics in the nuclear power plant. From the overall view of
the nuclear power plant, thermal energy via fission in the nuclear reactor core is utilized to finallygenerate electricity.
To appropriately design and control the nuclear reactor, we must understand and predict the behavior of neutrons and nuclear reactions. For this purpose, reactor physics has been developing as anengineering science to systematize the relevant knowledge.
The effective neutron multiplication factor keff is an important core-characteristics parameter tojudge whether the nuclear reactor core is subcritical, critical, or supercritical. The keff value indicates the ratio of fission-induced neutron-production to neutron loss (absorption or leakage). In the
nuclear reactor, fission power is constantly maintained at the “critical state”of the fission chain reaction.
To roughly predict the neutron multiplicity by the fission chain reaction, the point kinetics equation
is simple and useful. If we think of a point kinetic equation without delayed neutrons, this equation
is similar to that of the Susceptible-Infected-Removed (SIR) model, which is used in the epidemiology. However, if there were no delayed neutrons in the fission event, we could never control thefission chain power reaction. In other words, the delayed neutron plays an important role to control
the fission power in the actual nuclear reactor core by humans.
In order to predict the macroscopic and average behavior of neutrons, the Boltzmann neutron transport equation is utilized as the master equation. Note that the rigorous Boltzmann equation is toocomplicated to obtain the solution. At the dawn of the nuclear age, scientists and engineers simplified the prediction model based on ingenious approximations such as diffusion and Fermi-age
theories. Recently, as computing performance and computational science improve, we can accurately solve the numerical solution of the Boltzmann equations as much as possible. At the end of
this tutorial, I will briefly explain unique numerical analysis methods, which have been developed
and utilized in the field of reactor physics. Through this tutorial, I would like to promote understanding that the nuclear data such as microscopic nuclear cross section are essential input data for thereactor physics analysis.

Poster / 45

Development of Evaluation Method of Uncertainty of Radioactivity by Propagating Nuclear Data Covariance for Clearance Verification in Decommissioning of Nuclear Power Plants
Author: Tatsuki AMITANI 1
Co-authors: Tsunenori INAKURA 1 ; Naoki YAMANO 2 ; Ken-ichi TANAKA 3 ; Chikako ISHIZUKA 1 ; Masato
WATANABE 4 ; Ryoji MIZUNO 5 ; Satoshi CHIBA 1
1

Tokyo Institute of Technology

2

Tokyo Institute of Technology

3

The Institute of Applied Energy

4

Chubu Electric Power Co., Inc.

5

Chuden CTI Co., Ltd.

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To optimize disposal of low-level radioactive waste originating from decommissioning of nuclear
facilities, required are 1) reliable assessment of radioactivity level by calculation and measurementand 2) a good estimate of the uncertainty of those results for the classification of radioactive waste.
In order to improve the reliability of the calculations in clearance verification, we established aprocedure of estimating the uncertainty of radioactivity concentration due to that of nuclear data.
For that, we estimated covariance of neutron cross sections of important nuclides that account forover 90 % in ΣD/C of concrete material and carbon steel by employing a propagation of uncertainties
in the resonance parameters and statistical model parameters with nuclear data code group T6. Here,D stands for radioactivity concentration, and C stands for clearance level. Then, we developed a
new method to calculate uncertainty of radioactivity with Total Monte Carlo method by connecting
randomly perturbed endf-format files generated by the T6 calculation to a cross section processing
code NJOY and an activation calculation code ORIGEN2 using ORLIBJ40, a set of cross section library
based on JENDL-4.0. It was concluded that the uncertainty of the radioactivity due to that of nuclear
data for nuclides which dominate the ΣD/C is sufficiently small, and the main factor of uncertaintyof radioactivity comes from that of the neutron flux.

Poster / 47

Development of a neutron detector for nuclear data measurement
using high-intensity neutron beam
Author: Hideto Nakano1
Co-authors: Tatsuya Katabuchi 2 ; Gerard Rovira Leveroni 3 ; Yu Kodama 4 ; Kazushi Terada 5 ; Atsushi Kimura 3 ;Shoji Nakamura 3 ; Shunsuke Endo 3
1

Tokyo Institute of Technology

2

Tokyo Institute of Technology

3

JAEA

4

Tokyo Tech

5

Kyoto University

Highly precise neutron nuclear data is required in nuclear transmutation research of long-lived minor actinides (MA) in nuclear waste. In neutron capture cross section measurement, monitoring thenumber of the incident neutrons is necessary. However, in measurement with J-PARC/ANNRI, direct neutron monitoring system has not been employed. To make measurement with ANNRI morerobust, an additional neutron beam monitor is required. Conventional neutron detectors cannot
be used as a beam monitor at ANNRI because of two reasons, high counting rate environment and
gamma-flash. The neutron flux at ANNRI is one of the highest in the world. Gamma-flash, an intense
gamma-ray burst produced when the proton beam pulse bombards the spallation target, can paralyze a detector generally used in nuclear data measurement. In general, a semiconductor detector
or an inorganic scintillator, which is adopted for a neutron detector, has relatively longer responsetime and is unsuitable for beam monitoring at ANNRI.
Therefore, a combination of a thin plastic scintillator and a 6 LiF foil was selected as a detection
system, whose fast response enabled detecting neutrons at a high counting rate. Low gamma raysensitivity of a thin plastic scintillator allows measuring fast TOF region without count loss or detector paralysis. The geometry of the 6 LiF foil, the plastic scintillator, and photomultiplier tube (PMT)
was designed. The optimal thickness of the 6 LiF foil was determined with simulation codes, SRIM
and PHITS. A 6 LiF foil was made by vacuum deposition method. A test detector system was built to
study the feasibility of the method.
The detector system was tested under the high neutron irradiation condition at J-PARC /ANNRI. A
neutron TOF spectrum was successfully measured without significant count loss or detector paralysis. A neutron energy spectrum was driven from difference of TOF spectrum with and without
6
LiF. The neutron spectrum was compared with a past neutron spectrum and good agreement was
obtained. Statistic error was 0.68 % at 6.0 meV even though measurement times in this study waspretty short (~11 min).

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Poster / 48

Study of the fission path energy of U-236 using microscopic meanfield model
Author: Kazuki Fujio 1
Co-authors: Satoshi Chiba 1 ; Shuichiro Ebata 2 ; Tsunenori Inakura 1
1

Tokyo Institute of Technology

2

Saitama university

Microscopic mean-field model is one of strong methods for providing and improving fission-related
nuclear data.
It needs appropriate effective interaction, but there is no effective interaction designed for fissionpath.
In order to tackle this problem, we calculate the U-236 potential energy surface with respect to theelongation of a nucleus and the mass asymmetry with existing Skyrme effective interactions.
We report the energy characteristics of potential energy surface and important parts for correcting
the fission barrier.

Tutorial / 49

Roles and Current Status on Reactor Physics Experiment in Research Reactors
Author: Cheol Ho Pyeon1
1

Kyoto University

Nuclear reactors are mainly categorized as two parts: a commercial power reactor; a test and research
reactor for generating electric power and conducting research of radiation utilization, respectively.
Of two reactors, main roles of the test and research reactor are to conduct the research and development of nuclear engineering and radiation detection fields with the use of radiation, including
neutron, alpha-ray, beta-ray, gamma-ray, and so on, and to contribute to the education of young generation. Many research reactors are importantly equipped with experimental facilities to research
objectives, including irradiation holes, neutron beams and spectrum shift changers, although thecommercial reactors insufficiently meet the items. An index of classification of research reactors is
to provide a wide range of neutron spectrum and thermal reactor power, with the combined use of
nuclear fuel, moderators, reflectors and coolant materials by varying the kinds, the geometries, theconfigurations and the utilization purposes.
Another part of the presentation is to contain the feasibility study on the accelerator-driven system(ADS) conducted for nuclear transmutation analyses with the combined use of the solid-moderated
and solid-reflected core and the fixed-field alternating gradient (FFAG) accelerator, in the Institutefor Integrated Radiation and Nuclear Science, Kyoto University. Through the experimental analyses by MCNP with major nuclear data libraries (JENDL-4.0. ENDF/B-VII.1, JENDL/HE-2007 andJENDL/D-99), static and kinetic parameters of reactor physics are interestingly revealed for nuclear
transmutation of minor actinides (Np-237 and Am-241) and uncertainty quantification of a coolantmaterial (lead and bismuth), with respect to ADS. Additionally, experimental education programs fordomestic and overseas students conducted at the Kyoto University Critical Assembly are introducedin the presentation.

Poster / 50

The fission fragments of neutron-rich nuclei by the Langevin method
toward application to r-process calculations
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Author: Mizuki Okubayash1
Co-authors: Yoshihiro Aritomo 1 ; Shoya Tanaka 2 ; Shoma Ishizaki 3 ; Shota Amano 1 ; Nobuya Nishimura 4
1

Kindai University

2

Kindai University, Japan Atomic Energy Agency

3

Kindai university

4

Riken

Nuclear fission plays an essential role in nucleosynthesis by the rapid-neutron-capture process (rprocess), which is a cosmic origin of heavy elements beyond iron. For very neutron-rich environments in neutron star mergers, the strong r-process can be achieved, and the nucleosynthesis pathgoes into the trans-uranium region. In such conditions, fission is important to shape the r-process
abundances due to fission recycling, which determined the termination of the r-process in the heavy
nuclei region. Besides abundance prediction, fission is also a key role as the main heating source ofkilonovae, which are electromagnetic transients of neutron star mergers. A sign of fission heating
may have been observed in the light curve of the kilonova associated with the gravitational wave,
GW170817. The precise understanding of fission becomes much crucial in the era of gravitational
astronomy.
In this study, we calculate the fission-fragment mass distributions of very neutron-rich nuclei, which
are important for the nucleosynthesis calculations of the r-process, but experimental nuclear data
is not available. We adopt the Langevin method [1], widely adopted in the study of low-energy fission in the past few years. We found that the calculated mass distributions for uranium, of which
Z distribution is calculated with UCD (unchanged charge distribution assumption), well reproduce
experimental data in JENDL (232 U to 238 U) [2]. We also found that the fission distribution changes
from the two peak feature (asymmetric fission) to the one-peak (symmetric fission) as the neutron
number increases. The confirmation by future experiments would be desirable for these theoreticalpredictions to develop a complete theory set of fission distributions applicable to r-process nucleosynthesis simulations.
[1] S. Tanaka, Y. Aritomo, Y. Miyamoto, K. Hirose, and K. Nishio PRC 100, 064605 (2019).
[2] K. Shibata, O. Iwamoto et al.: “JENDL-4.0: A New Library for Nuclear Science and Engineering,”
J. Nucl. Sci. Technol. 48(1), 1-30 (2011).

Poster / 51

Comparison of photon spectra emitted from fuel debris using different decay data libraries
Authors: Taichi Matsumura1 ; Manabu Fujita2 ; Keisuke Okumura2
1

Japan Atomic Energy Agency

2

Japan Atomic Energy Agency

We require reliable nuclear data that can appropriately evaluate the radiation characteristics of fueldebris for the purpose such as development of new sensors, non-destructive assay technologies andoptimization of radiation shielding. In the past, even if different results were obtained dependingon calculation codes, it was difficult to clarify what caused the differences. To overcome it, we havedeveloped a new reliable code to calculate radiation decay and radioactive source spectra that canaccurately treats with large amounts of nuclides and all decay modes in the decay data file.
As the first step, we compared the photon spectra of fuel debris by using the recent decay data files:
JENDL/DDF-2015, decay sub-libraries of ENDF/B-VIII.0 and JEFF-3.3. As shown in Fig.1, the resultof JENDL/DDF-2015 is smaller than those of ENDF/B-VIII.0 and JEFF-3.3. This is mainly caused by
the following reasons:(1) X-ray data of 137mBa (T1/2 =2.6 min.) in JENDL/DDF-2015 is missing. The 137mBa is generated
from β- decay from large amount of 137Cs (T1/2 = 30 years) and it will remain for a long time byradiation equilibrium.
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/ Book of Abstracts(2) Gamma ray data of 241Am in 60 keV is missing in JENDL/DDF-2015.
(3) Gamma ray data of 106Rh (T1/2 = 2 hour) is missing in JENDL/DDF-2015 in the energy range
from 3.0 to 3.4 MeV. The 106Rh is in the radiation equilibrium with 106Ru (T1/2=1.0 year)
In the presentation, we will report requests for the modifications on the decay schemes and branching ratios of decay modes for the next JENDL decay data file.

Poster / 52

Nuclide production cross sections of natLu target irradiated with
0.4-, 1.3-, 2.2-, 3.0-GeV protons
Authors: Hayato Takeshita1 ; Shin-ichiro Meigo2 ; Hiroki Matsuda3 ; Hiroki Iwamoto4 ; Keita Nakano5 ; Yukinobu
Watanabe1 ; Fujio Maekawa6
1

Kyushu University2

J-PARC/JAEA

3

J-PARC Center, JAEA

4

Japan Atomic Energy Agency

5

JAEA

6

JAEA

Reliable assessment of radioactivity in target and structural materials for high-energy accelerator
facilities such as accelerator-driven systems and spallation neutron sources requires detailed information on nuclide production cross sections by spallation reactions. To obtain the systematic crosssection data for nuclide productions by spallation reactions, we have conducted irradiation experiments at Japan Proton Accelerator Research Complex (J-PARC). So far, we have measured nuclide
production cross sections for light to medium-heavy target elements (Z≤47) with proton energies
ranging from 0.4 to 3.0 GeV. To investigate heavier target elements, we conducted an experiment fortarget elements with atomic number around Z=70, including nat Lu (Z=71) target.
Four sets of Ho (90mg/cm2 ), Lu (100mg/cm2 ), and Re (210mg/cm2 ) foils were packed in aluminum
containers together with 0.1-mm-thick aluminum catchers to avoid recoil contamination. Each set oftargets was irradiated with 0.4-, 1.3-, 2.2-, and 3.0-GeV protons accelerated by 3-GeV Rapid Cycling
Synchrotron (RCS). The beam current was monitored by a current transformer installed in front of
the irradiation position. After the irradiation, gamma-rays emitted from the samples were detectedby two high-purity Germanium detectors (relative efficiency 20%, Canberra Co., Ltd.).
The measured cross sections were compared with theoretical predictions by Particle and Heavy Ion
Transport code System (PHITS) [1], and INCL++/ABLA[2,3]. The figure shows experimental andcalculated nat Lu(p, X)nat Be reaction cross sections. INCL/GEM model implemented in PHITS underestimated the experimental cross sections by a factor of about 2.
In the presentation, we will report our experimental results for the natLu target, and more detailed
discussion on reaction mechanics will be given.
References[1] T. Sato, et al., J. Nucl. Sci. Technol. 55, pp.684 (2018).
[2] D. Mancusi et al., Phys. Rev. C 91:034602 (2015).
[3] A. Kelic et al., Proceedings of Joint ICTP-IAEA Advanced Workshop on Model Codes for Spallation Reactions, ICTP Trieste, Italy pp.181 (2008).

Poster / 53

A New Method to Reduce Systematic Uncertainties of Capture
Cross Section Measurement Using a Sample Rotation System
Author: Yu Kodama1
Co-authors: Tatsuya Katabuchi 1 ; Gerard Rovira 2 ; Hideto Nakano 1 ; Kazushi Terada 3 ; Atsushi Kimura 4 ; ShojiNakamura 4 ; Shunsuke Endo 4

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1

Tokyo Institute of Technology

2

Japan Atomic Energy Agency/日本原子力研究開発機構

3

Kyoto University

4

Japan Atomic Energy Agency

Precise nuclear data for neutron-induced reactions are necessary for the design of nuclear transmutation system. Nevertheless, current uncertainties of nuclear data for minor actinide (MA) does notachieve requirements for the design of transmutation facilities. Measurements of the neutron capture cross section are ongoing at the Accurate Neutron Nucleus Reaction measurement Instrument(ANNRI) in the Materials and Life science experiment Facility (MLF) of the Japan Proton Accelerator
Research Complex (J-PARC). The determination of an incident neutron flux for measurements ofneutron capture cross section is one of the main causes that affect the final uncertainty of the crosssection results.
In the present work, we suggest a new method to reduce systematic uncertainties of capture crosssection measurements. The method employs change of the self-shielding effect with sample rotation
angle. In the new technique, a sample area density of a boron sample which is used for measurements of the incident neutron spectrum. In capture cross section measurements in ANNRI, a boron
sample is placed to determine the incident neutron spectrum by counting 478 keV γ-ray from the10
B(n,αγ)7 Li reaction. The uncertainty of the boron sample area density that is usually calculated
from the mass and the area introduces the uncertainty of the incident neutron spectrum. In thismethod, the boron sample is tilted with respect to the neutron beam direction, thereby changing
the effective area. The neutron self-shielding effect increases with the effective area density. This
results in change of the shapes of time-of-flight(TOF) spectrum of 478 keV γ-ray counts form the10
B(n,αγ)7 Li reaction with the tilted angle. Comparing the difference of the TOF spectra at different
angles and assuming the 1/v energy dependence of cross section of the 10 B(n,αγ)7 Li reaction, thearea density of the boron sample can be determined without using the sample mass and area.
Theoretical and experimental studies on the new method are ongoing. Calculation using Monte
Carlo simulation code PHITS were carried out to study the feasibility of the present method. Test
experiments using a sample rotation system at ANNRI were also performed. Preliminary results will
be given in this poster session.

Poster / 54

Measurement of neutron total cross sections of Sn-Pb alloys insolid and liquid states
Author: Takuya Uemura 1
Co-authors: Jun-ichi Hori 1 ; Kazushi Terada 2 ; Tadafumi Sano 3 ; Jun Nishiyama 4 ; Rei Kimura 5 ; Ken Nakajima
2

1

Kyoto University

2

Kyoto University

3

Kindai University

4

Tokyo Institute of Technology

5

Toshiba Energy Systems ＆ Solutions Corporation / 東芝エネルギーシステムズ

Recently, a small modular reactor (SMR) with inherent and passive safety has been receiving attention all over the world. In Japan, a very small modular reactor, namely, MoveluX<sup>TM</sup>(MobileVery-Small reactor for Local Utility in X-mark) has been developing by Toshiba Energy Systems ＆Solutions Corporation. MoveluX<sup>TM</sup> is a thermal reactor that uses a calcium hydride
as a neutron moderator. The use of a Sn-Pb alloy as an in-core heat transport medium is being considered. The Sn-Pb alloy is in a solid state when the reactor is started, and becomes liquid since thecore temperature reaches 660℃ during operation. Therefore, the total cross section data of the Sn-Pb
alloy is important for evaluating the effect of the change in the total cross section depending on thestate of Sn-Pb alloy on the reactor characteristics. However, there are no reports on experimental
data for total cross section of Sn-Pb alloys in both solid and liquid states in spite of the fact that
it is important data for nuclear engineering. In the present study, the neutron total cross section
was obtained from neutron transmission measurements by the time-of-flight (TOF) method using
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the Kyoto University Institute for Institute for Integrated Radiation and Nuclear Science –Linear Accelerator (KURNS-LINAC). The sample temperature was changed from room temperature (solid) up
to 300℃ (liquid). The total cross sections of solid and liquid states were compared and the change
in Bragg edge due to the difference of crystal structure was observed in the energy region below
0.01 eV. Comparing the total cross sections of the solid and the solid resolidificated after melting, it
was confirmed that some Bragg edges, which are thought to be due to the crystal structure of Pb,
disappeared by the resolidification. At the poster presentation, the detail of the total cross section
measurement experiment and the results obtained so far will be discussed.

Poster / 55

Comparison of double-differential cross sections between JENDL/PD2016.1 and experimental data for photo-neutron production of
medium-heavy nuclei at 16.6 MeV
Author: Kim Tuyet Tran1
Co-authors: Yasuhito Sakaki 2 ; Toshiya Sanami 3 ; Hirohito Yamazaki 3 ; Toshiro Itoga 4 ; Akihiro Takeuchi 5 ;Miyamoto Shuji 6 ; Yoshihiro Asano 6
1

SOKENDAI/KEK

2

KEK

3

KEK/SOKENDAI

4

JASRI

5

QST

6

University of Hyogo

Corresponding Author: tuyet@post.kek.jp

The double differential cross-section (DDX) of the photoneutron is an important quantity for radiation shielding and shielding calculation of the electron accelerator design. Shielding calculation
is usually carried out by Monte Carlo simulation codes, which use the nuclear data library in thecalculation. We measured the DDXs of the (γ, xn) reaction using 16.6 MeV polarized photon onnat.
Pb, 197 Au, nat. Sn, nat. Cu, nat. Fe, and nat. Ti targets [1], and showed the neutron spectra including the evaporation and direct components. In this presentation, we compared the DDXs from thephotonuclear data JENDL/PD-2016.1 and the experiment to check their consistency. The DDXs wereextracted from the JENDL/PD-2016.1 library by our python-based software. The abundances of eachtarget’s isotopes were considered in calculating the DDXs from the JENDL/PD-2016.1 library. This
comparison showed the differences in the photoneutron’s energy distributions, and the differenceswere mostly in the direct component. The evaporation components were found in both JENDL/PD2016.1 and the experimental data; however, they were not totally consistent. This result can be thefirst comparison of the DDXs from JENDL/PD-2016.1 and the experiment. The quantitative comparison and discussion will be presented at the symposium.
Keywords: differential double cross-section photoneutron, 16.6 MeV polarized photon, JENDL/PS2016.1.
[1] T.K. Tuyet et al., “Double differential cross section of the (γ, xn) reaction on medium-heavy
nuclei for 16.6 MeV polarized photons. 2020 Fall meeting of AESJ, Sep. 16th –18th.

Facility / 56

Nuclear data study for Accelerator Driven System at J-PARC
Author: Shin-ichiro Meigo1
1

J-PARC/JAEA

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In order to decrease the toxic waste produced at the nuclear reactor, a study of the Accelerator Driven
System (ADS) is going around the world. Since the neutron production target at ADS is designed tobe irradiated by protons in the kinetic energy of several GeV, a study with the high-energy particles in
the kinetic energy region around GeV is essential for the research and development of ADS. However,many accelerator facilities using several GeV-protons, which were built 1970’s, are going to shut
down due to their lifetime. Eventually, the facilities to be able to use protons with several GeV are
scarce in the world. In Japan, J-PARC can only apply for the sake of ADS using the hadron including
proton. At the 3-GeV proton synchrotron (RCS) facility and the beam transport line, some studies
are going at J-PARC aimed for nuclear data of ADS.
In this session, some results of the experiment related to nuclear data for ADS are introduced, suchas nuclide production cross-section induced by proton and displacement cross-section.

NuclearMedicine / 57

Development of Radioisotopes Production Method by Acceleratorbased Neutron: Activity at Kyushu University 2020
Author: Tadahiro Kin1
1

Kyushu Unversity

Radioisotopes (RIs) production using deuteron accelerator-based neutrons has been studying at
Kyushu University. We especially focus on neutrons generated via the C or Be(d, n) reactions ina target whose thickness is thicker than the deuteron range. These reactions are selected because,(1) high intense neutrons having high kinetic energy are possible to be generated by the elastic andnon-elastic break-up reaction of deuterons, and (2) neutron energy spectrum has maximum arounda half incident deuteron energy, i.e. the spectrum shape can be adjusted by varying deuteron energy.
The study has been conducted by the two approaches: proposal of new production routes or new
RIs with the accelerator-based neutron method and systematic measurements of double-differential
thick-target neutron yields (DDTTNYs) up to 40 MeV. Present paper shows some example of pastworks (high purity 64Cu production starting from
Zn which includes multiple stable isotopes),present status (chemistry, systematic DDTTNY measurement results), and future prospects (covariance application for neutron spectrum unfolding to take nuclear data uncertainty into account) of
our project.

NuclearMedicine / 58

Measurements of production cross sections of medical radioisotopes via charged-particle induced reactions / 荷電粒子入射反応による医療用 RI 生成断面積測定実験
Author: Masayuki / 正幸 AIKAWA / 合川1
1

Hokkaido University / 北海道大学

Radioisotopes can be used for a variety of applications, e.g., radiotherapy and diagnostics in nuclear
medicine. There are basically several reactions to produce each radioisotope. Investigations of suchreactions are necessary to find better reactions with less byproducts and with higher cost effectiveness. Production cross sections of the radioisotopes are thus important nuclear data. However, there
still exist a lack of data and data with large errors. It is necessary to obtain more accurate and reliabledata for the application. Recent technical development of accelerators and detectors enables us toreach such data.
We focus on charged-particle-induced reactions among the possible reactions for the production.
The charged-particle-induced reactions have an advantage to be able to produce radioisotopes withatomic numbers different from those of targets. We can expect to chemically separate the reaction
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products from the targets and to obtain the radioisotopes with high specific activity.
Experiments to measure the production cross sections are performed at RIKEN, Japan and ATOMKI,
Hungary. The well-developed methods, stacked foil activation technique and high-resolution gammaray spectrometry, are adopted. The targets consisted of thin foils were irradiated with the chargedparticles beams. Gamma-rays emitted from the irradiated foils without chemical separation were
measured by HPGe detectors. Nuclear data required for deduction of cross sections were obtained
from online databases. The cross sections of the monitor reactions were compared with the IAEA
recommended values to assess the beam parameters and target thicknesses.
The production cross sections can be derived and compared with previous studies and theoreticalmodel calculation in the TENDL-2019 library. Thick target yields of the products for practical use
can also be derived from the measured cross sections. The results are expected to contribute nuclear
medicine.
We report our research activity on the experiments for the production cross sections of several medical radioisotopes.

Poster / 60

Research for nuclear transmutation of high-radiotoxic nuclide90
Sr via proton- and deuteron-induced reactions
Author: Riku Matsumura 1
1

Saitama University

Processing of spent fuel from nuclear power plants is a worldwide problem. The high-level radioactive waste is the product after the reprocessing of spent fuel, which includes minor actinides andfission products of radioactive waste. Especially, 90 Sr (T1/2 = 28.8 years) is the highest radiotoxic
nuclide in the fission products. It is highly desired to develop nuclear transmutation technology
using accelerator facilities to reduce these harmful nuclides. The simplest way can be to irradiatea neutron beam on the radioactive waste. However, it is not well known that 90 Sr is transmuted
into how much and which nuclide in this reaction. Therefore, it is essential to study, in advance, thereaction-cross-sections to each nuclide from 90 Sr. From this point of view, the inverse kinematics,
i.e. including the 90 Sr beam incident on light-particle targets, is an effective method the reaction
products can be identified at the forward directions.
To realize this purpose, we have planned the proton- and deuteron-induced reaction-cross-section
measurements in inverse kinematics and performed the experiment using the BigRIPS separator [1]and the ZeroDegree spectrometer [1] at the RIKEN Radioactive Isotope Beam Factory. The radioactive 90 Sr beam with 104 MeV/u, produced and separated in the BigRIPS, incident on the C, CH2 , andCD2 targets. The reaction products in the forward directions were transferred to the ZeroDegree andidentified using the detectors at the focal plane. The reaction-cross-sections were obtained from themeasured yields of each reaction channel. At this time, the contributions from carbon and beam-line
materials were subtracted as a background. The obtained reaction-cross-sections were compared to
the PHITS calculation [2] and the data with different energy of 185 MeV/u [3].
[1] T. Kubo, et al., Progr. Theor. Exp. Phys. 2012, 03C003 (2012).
[2] T. Sato, et al., J. Nucl. Sci. Technol. 50, 913 (2013).
[3] H. Wang, et al., Phys. Lett. B 754, 104 (2016).

Poster / 61

Theoretical evaluation of non-resonant background strength inbinary breakup reaction
Authors: Riu Nakamoto1 ; Makoto Ito2 ; Saito Akito3 ; Shimoura Susumu4

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1

Department of Pure and Applied physics, Kansai University

2

Department of Pure and Applied physics, Kansai University/関西大学システム理工学部物理・応用物理学科

3

Department of Radiation Oncology,

4

Center for Nuclear Study, School of Science, University of Tokyo

Inelastic scattering is useful tool to explore the nuclear structure in the excited states. In particular,
the inelastic excitation to the continuum energy states above the particle decay threshold, which isoften called breakup reaction, is very important because we can pin down a specific nuclear structure by controlling the exit channels, which are the combination of the emitted fragments.
A typical and good example about the inelastic scattering to the continuum can be seen in the
breakup reaction of 12 Be into the α + 8 He and 6 He + 6 He channels. In this experiment, the careful multi-pole decomposition analysis (MDA) was performed, and the MDA analysis elucidates thatmany resonant states with a sharp width exist in the spins from J π = 0+ to 8+ . The 0+ resonancesin the α + 8 He channel appear in a close energy spacing of 0.5 MeV in the lower energy region
below Ee.x. ≤ 15 MeV, which is quite consistent to the energy scheme expected from the cluster
resonances.
Basic and important quantities in the analysis of the resonance enhancement embedded in the continuum strength are the resonance parameters, such as the resonance energy and the decay width. In
determining the resonance parameters, the evaluation of the non-resonant background strength isindispensable because the resonant enhancement, which has the strong energy dependence, are embedded in the non-resonant background contribution with a broad structure. Since the backgroundstrength is structure-less and must have the weak energy dependence, the shape of the non-resonantbackground strength is often assumed by the simple analytic function or evaluated from the simple
reaction mechanism, such as the direct breakup without the final state interaction between the decaying fragments.
In this report, we investigate the structure of the non-resonant background continuum, which is
generated by the binary breakup reaction, and explore the prescription to evaluate the backgroundcontribution by extending the Migdal-Watson formula for the s-wave breakup in the charge neutral
system. In the calculation of the strength function for the binary breakup, we employ the complex
scaling method (CSM), which is a powerful tool to describe the few-body continuum states. We
handle the breakup reaction of 20 Ne into α + 16 O and 12 Be into α + 8 He. From the CSM calculationand the Migdal-Watoson theory, we propose the analytic function, which is appropriate to evaluate
the background contribution for the binary breakup.

Facility / 62

Proposal of 1 A class deuteron single cell linac / 大強度重陽子加速器 ImPACT2017 の提案
Author: Hiroki Okuno1
1

RIKEN Nishina center for accelerator-based science

A 1-ampere-class high-intensity deuteron linac (ImPACT2017 model) is proposed for mitigating longlived fission products (LLFPs) by nuclear transmutation. This accelerator consists of single-cell rf cavities with magnetic focusing elements to accelerate deuterons beyond 1A up to 200MeV/u.

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