Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Iwamoto, Yosuke; Matsuda, Hiroki*; Meigo, Shinichiro; Yonehara, Katsuya*; Pellemoine, F.*; Liu, Z.*; Lynch, K.*; Yoshida, Makoto*; Yabuuchi, Atsushi*; Yoshiie, Toshimasa*; et al.
Nuclear Instruments and Methods in Physics Research B, 557, p.165543_1 - 165543_8, 2024/12
Times Cited Count：2 Percentile：41.12(Instruments & Instrumentation)The number of displacements per atom is widely used as an indicator of irradiation damage to materials in proton accelerator facilities. Experiments have been carried out on protons below 3 GeV to verify the dpa of metallic materials. However, the dpa for high-energy protons above 3 GeV has not been measured. In order to validate the displacement cross sections of metals in the high-energy region, the electrical resistivity changes of aluminium, copper and tungsten wires at a temperature of 8 K were measured using protons with energy of 120 GeV. The results show that the conventional irradiation damage model of PHITS overestimates the experimental data. On the other hand, the calculation results using the athermal recombination correction model were in agreement with the experimental data.
Iwamoto, Yosuke; Yoshida, Makoto*; Meigo, Shinichiro; Yonehara, Katsuya*; Ishida, Taku*; Nakano, Keita; Abe, Shinichiro; Iwamoto, Hiroki; Spina, T.*; Ammigan, K.*; et al.
JAEA-Conf 2021-001, p.138 - 143, 2022/03
To predict the operating lifetime of materials in high-energy radiation environments at proton accelerator facilities, Monte Carlo code are used to calculate the number of displacements per atom (dpa). However, there is no experimental data in the energy region above 30 GeV. In this presentation, we introduce our experimental plan for displacement cross sections with 120-GeV protons at Fermilab Test Beam Facility. Experiments will be performed for the US fiscal year 2022. We developed the sample assembly with four wire sample of Al, Cu, Nb and W with 250-
m diameter and 4-cm length. The sample assembly will be maintained at around 4 K by using a cryocooler in a vacuum chamber. Then, changes in the electrical resistivity of samples will be obtained under 120-GeV proton irradiation. Recovery of the accumulated defects through isochronal annealing, which is related to the defect concentration in the sample, will also be measured after the cryogenic irradiation.
Ishida, Taku*; Wakai, Eiichi; Makimura, Shunsuke*; Casella, A. M.*; Edwards, D. J.*; Prabhakaran, R.*; Senor, D. J.*; Ammigan, K.*; Bidhar, S.*; Hurh, P. G.*; et al.
Journal of Nuclear Materials, 541, p.152413_1 - 152413_12, 2020/12
Times Cited Count：28 Percentile：91.49(Materials Science, Multidisciplinary)A high-intensity proton beam exposure with 181 MeV energy has been conducted at Brookhaven Linac Isotope Producer facility on various material specimens for accelerator targetry applications, including titanium alloys as a beam window material. The radiation damage level of the analyzed capsule was 0.25 dpa at beam center region with an irradiation temperature around 120 degree C. Tensile tests showed increased hardness and a large decrease in ductility for the dual 
+
-phase Ti-6Al-4V Grade-5 and Grade-23 extra low interstitial alloys, with the near alpha-phase Ti-3Al-2.5V Grade-9 alloy still exhibiting uniform elongation of a few % after irradiation. Transmission Electron Microscope analyses on Ti-6Al-4V indicated clear evidence of a high-density of defect clusters with size less than 2 nm in each alpha-phase grain. The -phase grains did not contain any visible defects such as loops or black dots, while the diffraction patterns clearly indicated omega-phase precipitation in an advanced formation stage. The radiation-induced omega-phase transformation in the -phase could lead to greater loss of ductility in Ti-6Al-4V alloys in comparison with Ti-3Al-2.5V alloy with less -phase.
(
,
)
and (,)
reactions for 
=1.5-2.4 GeVZegers, R. G. T.*; Sumihama, Mizuki*; Ahn, D. S.*; Ahn, J. K.*; Akimune, Hidetoshi*; Asano, Yoshihiro; Chang, W. C.*; Dat
, S.*; Ejiri, Hiroyasu*; Fujimura, Hisako*; et al.
Physical Review Letters, 91(9), p.092001_1 - 092001_4, 2003/08
Times Cited Count：131 Percentile：94.49(Physics, Multidisciplinary)no abstracts in English
= +1 Baryon resonance in photoproduction from the neutronNakano, Takashi*; Ahn, D. S.*; Ahn, J. K.*; Akimune, Hidetoshi*; Asano, Yoshihiro; Chang, W. C.*; Date, S.*; Ejiri, Hiroyasu*; Fujimura, Hisako*; Fujiwara, Mamoru; et al.
Physical Review Letters, 91(1), p.012002_1 - 012002_4, 2003/07
Times Cited Count：1039 Percentile：99.84(Physics, Multidisciplinary)no abstracts in English
Iwamoto, Yosuke; Hashimoto, Shintaro; Yoshida, Makoto*; Iwamoto, Hiroki; Meigo, Shinichiro; Yonehara, Katsuya*; Spina, T.*; Hurh, P.*
no journal, ,
For defect production, it is the number of recoils weighted by the damage energy produced in each recoil that is most important. This quantity is determined by "weighed" the recoil spectra by the damage energy produced in each recoil. However, the damage energy spectra have not been investigated yet for the proton energy range from several MeV to hundred GeV, where recoil is regarded as nuclear reaction product. In this work, we calculated damage energy spectra of all nuclear reaction products under high energy proton irradiation on tungsten with the energy range from 10 MeV to 120 GeV using the PHITS code. The average damage energy of tungsten was 30-80 keV including nuclear elastic and non-elastic components and that of lutetium was 550-900 keV including non-elastic component. In this presentation, we will also introduce our experimental plan for measurement of dpa cross sections with 120 GeV protons at Fermi National Accelerator Laboratory (FNAL).
raysYamazaki, Takumi; Takada, Chie; Nakamura, Keisuke; Sagawa, Naoki; Hoshi, Katsuya; Nakagawa, Takahiro; Takimoto, Misaki; Tanimura, Yoshihiko*; Takahashi, Fumiaki; Momose, Takumaro; et al.
no journal, ,
no abstracts in English
