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Jin, H.*; Choi, E. S.*; Wu, H.-C.*; Curro, N. J.*; Nawa, Kazuhiro*; Sato, Taku*; Kiyanagi, Ryoji; Ohara, Takashi; Klavins, P.*; Taufour, V.*
Physical Review B, 111(3), p.035103_1 - 035103_7, 2025/01
Times Cited Count:0 Percentile:0.00(Materials Science, Multidisciplinary)Baccou, J.*; Glantz, T.*; Ghione, A.*; Sargentini, L.*; Fillion, P.*; Damblin, G.*; Sueur, R.*; Iooss, B.*; Fang, J.*; Liu, J.*; et al.
Nuclear Engineering and Design, 421, p.113035_1 - 113035_16, 2024/05
Times Cited Count:6 Percentile:97.93(Nuclear Science & Technology)Kondo, Yasuhiro; Kitamura, Ryo; Fuwa, Yasuhiro; Morishita, Takatoshi; Moriya, Katsuhiro; Takayanagi, Tomohiro; Otani, Masashi*; Cicek, E.*; Ego, Hiroyasu*; Fukao, Yoshinori*; et al.
Proceedings of 31st International Linear Accelerator Conference (LINAC 2022) (Internet), p.636 - 641, 2022/09
The muon linac project for the precise measurement of the muon anomalous magnetic and electric dipole moments, which is currently one of the hottest issues of the elementary particle physics, is in progress at J-PARC. The muons from the J-PARC muon facility are once cooled to room temperature, then accelerated up to 212 MeV with a normalized emittance of 1.5 mm mrad and a momentum spread of 0.1%. Four types of accelerating structures are adopted to obtain the efficient acceleration with a wide beta range from 0.01 to 0.94. The project is moving into the construction phase. We already demonstrated the re-acceleration scheme of the decelerated muons using a 324-MHz RFQ in 2017. The high-power test of the 324-MHz Interdigital H-mode (IH) DTL using a prototype cavity was performed in 2021. The fabrication of the first module of 14 modules of the 1296-MHz Disk and Washer (DAW) CCL will be done to confirm the production process. Moreover, the final design of the travelling wave accelerating structure for the high beta region is also proceeding. In this paper, the recent progress toward the realization of the world first muon linac will be presented.
Herranz, L. E.*; Jacquemain, D.*; Nitheanandan, T.*; Sandberg, N.*; Barr, F.*; Bechta, S.*; Choi, K.-Y.*; D'Auria, F.*; Lee, R.*; Nakamura, Hideo
Progress in Nuclear Energy, 127, p.103432_1 - 103432_14, 2020/09
Times Cited Count:6 Percentile:22.19(Nuclear Science & Technology)Carter, L. M.*; Crawford, T. M.*; Sato, Tatsuhiko; Furuta, Takuya; Choi, C.*; Kim, C. H.*; Brown, J. L.*; Bolch, W. E.*; Zanzonico, P. B.*; Lewis, J. S.*
Journal of Nuclear Medicine, 60(12), p.1802 - 1811, 2019/12
Times Cited Count:28 Percentile:80.64(Radiology, Nuclear Medicine & Medical Imaging)Voxel human phantoms have been used for internal dose assessment. More anatomically accurate representation become possible for skins or layer tissues owing to recent developments of advanced polygonal mesh-type phantoms and thus internal dose assessment using those advanced phantoms are desired. However, the Monte Carlo transport calculation by implementing those phantoms require an advanced knowledge for the Monte Carlo transport codes and it is only limited to experts. We therefore developed a tool, PARaDIM, which enables users to conduct internal dose calculation with PHITS easily by themselves. With this tool, a user can select tetrahedral-mesh phantoms, set radionuclides in organs, and execute radiation transport calculation with PHITS. Several test cases of internal dosimetry calculations were presented and usefulness of this tool was demonstrated.
Nakazawa, Yuga*; Bae, S.*; Choi, H.*; Choi, S.*; Iijima, Toru*; Iinuma, Hiromi*; Kawamura, Naritoshi*; Kitamura, Ryo; Kim, B.*; Ko, H. S.*; et al.
Nuclear Instruments and Methods in Physics Research A, 937, p.164 - 167, 2019/09
Times Cited Count:3 Percentile:28.35(Instruments & Instrumentation)A muon linac is under development for the precise measurement of the muon anomalous magnetic moment (-2) and electric dipole moment (EDM) with a reaccelerated thermal muon beam. An H
source driven by an ultraviolet light has been developed for the muon acceleration experiment. Prior to the acceleration experiment, a beamline commissioning was performed using this H
beam, since the accelerated muon intensity is very low. We successfully measured the magnetic rigidity, which is essential for identifying the accelerated muons. This H
source is capable of utilizing as a general-purpose beam source for other beamline.
Dioguardi, A. P.*; Yasuoka, Hiroshi*; Thomas, S. M.*; Sakai, Hironori; Cary, S. K.*; Kozimor, S. A.*; Albrecht-Schmitt, T. E.*; Choi, H. C.*; Zhu, J.-X.*; Thompson, J. D.*; et al.
Physical Review B, 99(3), p.035104_1 - 035104_6, 2019/01
Times Cited Count:10 Percentile:43.10(Materials Science, Multidisciplinary)We present a detailed nuclear magnetic resonance (NMR) study of Pu in bulk and powdered single-crystal plutonium tetraboride (PuB
), which has recently been investigated as a potential correlated topological insulator. The
Pu NMR spectra are consistent with axial symmetry of the shift tensor showing for the first time that
Pu NMR can be observed in an anisotropic environment and up to room temperature. The temperature dependence of the
Pu shift, combined with a relatively long spin-lattice relaxation time (
), indicate that PuB
adopts a nonmagnetic state with gaplike behavior consistent with our density functional theory calculations. The temperature dependencies of the NMR Knight shift and
imply bulk gaplike behavior confirming that PuB
is a good candidate topological insulator.
Otani, Masashi*; Sue, Yuki*; Fukao, Yoshinori*; Futatsukawa, Kenta*; Kawamura, Naritoshi*; Mibe, Tsutomu*; Miyake, Yasuhiro*; Shimomura, Koichiro*; Yamazaki, Takayuki*; Iijima, Toru*; et al.
Journal of Physics; Conference Series, 1067(5), p.052012_1 - 052012_7, 2018/09
Times Cited Count:1 Percentile:44.97(Physics, Particles & Fields)We have measured the muon beam profile after acceleration using a radio frequency quadrupole linac (RFQ). Positive muons are injected to an aluminum degrader and negative muoniums (Mu) are generated. The generated Mu
s are extracted by an electrostatic lens and accelerated to 89 keV by the RFQ. The accelerated Mu
s are transported to a beam profile monitor (BPM) through a quadrupole magnet pair and a bending magnet. The BPM consists of a micro-channel plate, a phospher screen, and a CCD camera. Measured profile in the vertical direction is consistent to the simulation. This profile measurement is one of milestones for realizing a muon linac for measurement of the muon anomalous magnetic moment at the Japan Proton Accelerator Research Complex.
Kim, B.*; Bae, S.*; Choi, H.*; Choi, S.*; Kawamura, Naritoshi*; Kitamura, Ryo*; Ko, H. S.*; Kondo, Yasuhiro; Mibe, Tsutomu*; Otani, Masashi*; et al.
Nuclear Instruments and Methods in Physics Research A, 899, p.22 - 27, 2018/08
Times Cited Count:7 Percentile:52.46(Instruments & Instrumentation)A beam profile monitor (BPM) based on a microchannel plate has been developed for muon beams with low transverse momentum for the measurement of the muon anomalous magnetic moment and electric dipole moment at high precision, with capability of diagnosing muon beams of kinetic energy range from a few keV to 4 MeV. The performance of the BPM has been evaluated using a surface muon beam at J-PARC and additionally with an ultraviolet (UV) light source. It has been confirmed that the BPM has a dynamic range from a few to 10 muons per bunch without saturation. The spatial resolution of the BPM has been estimated to be less than 0.30 mm. The positron background from muon decays is an obstacle in muon beam profile monitoring and a partial discrimination of the positrons has been achieved under discrete particle conditions.
Bae, S.*; Choi, H.*; Choi, S.*; Fukao, Yoshinori*; Futatsukawa, Kenta*; Hasegawa, Kazuo; Iijima, Toru*; Iinuma, Hiromi*; Ishida, Katsuhiko*; Kawamura, Naritoshi*; et al.
Physical Review Accelerators and Beams (Internet), 21(5), p.050101_1 - 050101_6, 2018/05
Times Cited Count:16 Percentile:75.43(Physics, Nuclear)Muons have been accelerated by using a radio-frequency accelerator for the first time. Negative muonium atoms (Mu), which are bound states of positive muons and two electrons, are generated from through the electron capture process in an aluminum degrader. The generated Mu
's are initially electrostatically accelerated and injected into a radio-frequency quadrupole linac (RFQ). In the RFQ, the Mu
's are accelerated to 89 keV. The accelerated Mu
's are identified by momentum measurement and time of flight. This compact muon linac opens the door to various muon accelerator applications including particle physics measurements and the construction of a transmission muon microscope.
Kim, S. B.*; Zhang, Y.*; Won, S. M.*; Bandodkar, A. J.*; Sekine, Yurina; Xue, Y.*; Koo, J.*; Harshman, S. W.*; Martin, J. A.*; Park, J. M.*; et al.
Small, 14(12), p.1703334_1 - 1703334_11, 2018/03
Times Cited Count:128 Percentile:96.25(Chemistry, Multidisciplinary)Adare, A.*; Afanasiev, S.*; Aidala, C.*; Ajitanand, N. N.*; Akiba, Y.*; Al-Bataineh, H.*; Alexander, J.*; Aoki, K.*; Aphecetche, L.*; Armendariz, R.*; et al.
Physical Review D, 84(1), p.012006_1 - 012006_18, 2011/07
Times Cited Count:33 Percentile:74.58(Astronomy & Astrophysics)We report on the event structure and double helicity asymmetry () of jet production in longitudinally polarized
collisions at
= 200 GeV. Photons and charged particles were measured by the PHENIX experiment. Event structure was compared with the results from PYTHIA event generator. The production rate of reconstructed jets is satisfactorily reproduced with the next-to-leading-order perturbative QCD calculation. We measured
= -0.0014
0.0037 at the lowest
bin and -0.0181
0.0282 at the highest
bin. The measured
is compared with the predictions that assume various
distributions.
Adare, A.*; Afanasiev, S.*; Aidala, C.*; Ajitanand, N. N.*; Akiba, Yasuyuki*; Al-Bataineh, H.*; Alexander, J.*; Aoki, Kazuya*; Aphecetche, L.*; Armendariz, R.*; et al.
Physical Review C, 83(6), p.064903_1 - 064903_29, 2011/06
Times Cited Count:192 Percentile:99.41(Physics, Nuclear)Transverse momentum distributions and yields for , and
in
collisions at
= 200 and 62.4 GeV at midrapidity are measured by the PHENIX experiment at the RHIC. We present the inverse slope parameter, mean transverse momentum, and yield per unit rapidity at each energy, and compare them to other measurements at different
collisions. We also present the scaling properties such as
and
scaling and discuss the mechanism of the particle production in
collisions. The measured spectra are compared to next-to-leading order perturbative QCD calculations.
Adare, A.*; Afanasiev, S.*; Aidala, C.*; Ajitanand, N. N.*; Akiba, Yasuyuki*; Al-Bataineh, H.*; Alexander, J.*; Aoki, Kazuya*; Aphecetche, L.*; Aramaki, Y.*; et al.
Physical Review C, 83(4), p.044912_1 - 044912_16, 2011/04
Times Cited Count:10 Percentile:54.83(Physics, Nuclear)Measurements of electrons from the decay of open-heavy-flavor mesons have shown that the yields are suppressed in Au+Au collisions compared to expectations from binary-scaled collisions. Here we extend these studies to two particle correlations where one particle is an electron from the decay of a heavy flavor meson and the other is a charged hadron from either the decay of the heavy meson or from jet fragmentation. These measurements provide more detailed information about the interaction between heavy quarks and the quark-gluon matter. We find the away-side-jet shape and yield to be modified in Au+Au collisions compared to
collisions.
Adare, A.*; Afanasiev, S.*; Aidala, C.*; Ajitanand, N. N.*; Akiba, Y.*; Al-Bataineh, H.*; Alexander, J.*; Aoki, K.*; Aphecetche, L.*; Armendariz, R.*; et al.
Physical Review D, 83(5), p.052004_1 - 052004_26, 2011/03
Times Cited Count:179 Percentile:98.34(Astronomy & Astrophysics)The PHENIX experiment at RHIC has measured the invariant differential cross section for production of ,
,
and
mesons in
collisions at
= 200 GeV. The spectral shapes of all hadron transverse momentum distributions are well described by a Tsallis distribution functional form with only two parameters,
and
, determining the high
and characterizing the low
regions for the spectra, respectively. The integrated invariant cross sections calculated from the fitted distributions are found to be consistent with existing measurements and with statistical model predictions.
Yang, H. L.*; Kim, Y. S.*; Park, Y. M.*; Bae, Y. S.*; Kim, H. K.*; Kim, K. M.*; Lee, K. S.*; Kim, H. T.*; Bang, E. N.*; Joung, M.*; et al.
Proceedings of 23rd IAEA Fusion Energy Conference (FEC 2010) (CD-ROM), 8 Pages, 2011/03
Because the 2010 operation of Korea Superconducting Tokamak Advanced Research (KSTAR) mainly aims to achieve strongly elongated and diverted plasma, all the necessary hardware systems to provide an essential circumstance for the plasma shaping were newly installed and upgraded in 2010. In this paper, general configuration of the upgraded systems described earlier will be outlined. Moreover, several key performances and test results of the systems will be also reported in summary.
Kang, J.-S.*; Kim, J. H.*; Sekiyama, Akira*; Kasai, Shuichi*; Suga, Shigemasa*; Han, S. W.*; Kim, K. H.*; Choi, E. J.*; Kimura, Tsuyoshi*; Muro, Takayuki*; et al.
Physical Review B, 68(1), p.012410_1 - 012410_4, 2003/07
Times Cited Count:21 Percentile:67.54(Materials Science, Multidisciplinary)no abstracts in English
Haga, Yoshinori; Matsumoto, Yuji; Tateiwa, Naoyuki; Matsuda, Tatsuma; Yamamoto, Etsuji; Choi, E. S.*; Bauer, E. D.*; Fisk, Z.
no journal, ,
no abstracts in English
Joung, S.*; Ji, Y.-Y.*; Choi, Y.*; Lee, E.*; Ji, W.*; Sasaki, Miyuki; Ochi, Kotaro; Sanada, Yukihisa
no journal, ,
KAERI (Korea Atomic Energy Research Institute) has developed the MARK A1 aerial survey system for unmanned aerial vehicles for use in contaminated areas. The MARK A1 system consists of a CZT detector, signal processing unit, and positioning and interface units to a PC on the ground. To validate the effectiveness of the detectors, field tests were conducted in high dose rate environments near the Fukushima Daiichi Nuclear Power Station. The JAEA and KAERI detectors were each mounted on an unmanned helicopter to make measurements at different altitudes. For both systems, the air dose rates obtained from the airborne survey gave results with a similar trend to the air dose rates obtained from the walking survey. Therefore, it is expected that MARK A1 can be used to quickly scan large and highly contaminated areas that are difficult for humans to access in the event of a nuclear accident.