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Meleshenkovskii, I.*; Van den Brandt, K.*; Ogawa, Tatsuhiko; Datema, C.*; Mauerhofer, E.*
European Physical Journal Plus (Internet), 139, p.565_1 - 565_9, 2024/07
Times Cited Count:0 Percentile:0.00(Physics, Multidisciplinary)Fast neutron inelastic scattering is a promising non-destructive assay technique for various analytical applications. As an active neutron interrogation technique, its performance is a function of various different factors and parameters that require optimization. Monte Carlo simulation codes are indispensable for such tasks. However, the internal simulation routines implemented in such codes can rely on different physical models that can yield discrepancies in the simulation results. In this work we conduct an intercomparison of PHITS and Geant4 codes performance in application to fast neutron inelastic scattering simulations. The goal of this paper is twofold. First, we explain the differences in code configuration with respect to gamma and neutron transport, as well as internal simulation routines. Second, we conduct a performance assessment of the two codes using two different measurement configurations. One configuration consisted of a source of gamma-rays in a broad energy range (100 keV - 9000 keV) and a CeBr detector. The other configuration consisted of a monoenergetic 2.5 MeV fast neutron source, Fe, Nd, Dy, B targets and a CeBr detector. Selected simulation configurations were chosen with a goal to compare the performance differences in neutron energy distribution, produced prompt gamma-rays and energy deposition in CeBr detector between the two codes. Results of our study reveal a good coherence of both codes performance in the application of fast neutron inelastic scattering simulations. The simulation geometries and observed differences are described in detail.
Meleshenkovskii, I.*; Ogawa, Tatsuhiko; Sari, A.*; Carrel, F.*; Boudergui, K.*
Nuclear Instruments and Methods in Physics Research B, 483, p.5 - 14, 2020/11
Times Cited Count:10 Percentile:63.90(Instruments & Instrumentation)For the purpose of fissile material detection, the technique to observe neutrons ejected from photo-fission induced by bremsstrahlung X-rays is being developed. This technique is advantageous in the sense that the machine can be compact compared to conventional neutron generators. However, photo-fission reaction cross sections are generally smaller than those of neutron-induced fission cross sections therefore optimization of the beam line is of high importance. In this study, we investigated the factors necessary to be optimized by using Monte-Carlo transport codes MCNP and PHITS. It was found that high-Z materials are advantageous to effectively produce bremsstrahlung X-rays but photons produce neutrons by secondary (,n) reactions resulting in mixing of prompt and delayed fission reactions. Moreover, secondary neutrons are produced not only inside the target but also in the materials surrounding the target. Therefore it is necessary to select elements whose neutron separation energy is high to suppress parasitic secondary neutrons.
Constantini, J.-M.*; Seo, P.*; Yasuda, Kazuhiro*; Bhuian, AKM S. I.*; Ogawa, Tatsuhiko; Gourier, D.*
Journal of Luminescence, 226, p.117379_1 - 117379_10, 2020/10
Times Cited Count:8 Percentile:51.44(Optics)Cathodo-luminescence is used for detection of lattice defects, in particular oxygen vacancies in ceramics induced by electrons. However, how oxygen vacancy production efficiency depends on sample temperature, incoming electron flux, and electron energy was not clear. In this study, oxygen vacancies were made in the specimens of CeO by irradiation of 400-1250 keV electrons and the cathodoluminescence from thus induced vacancies were observed by photo-fiber probe combined with CCD. As the result, the dependence of luminescence intensity on specimen temperature depends on the carrier trapping frequency and luminescence efficiency while luminescence center production/annihilation speed determines the dependency on the incoming electron flux. Moreover, radiation transport calculation conducted by the particle transport simulation code PHITS indicates that the number of electrons above the defect production threshold energy is vital to explain incoming electron energy dependence.
Meleshenkovskii, I.*; Ogawa, Tatsuhiko; Pauly, N.*; Labeau, P.-E.*
Nuclear Instruments and Methods in Physics Research B, 467, p.108 - 113, 2020/03
Times Cited Count:2 Percentile:21.81(Instruments & Instrumentation)CdZnTe (CZT) semiconductor detectors are featured by the fact that it can be operated in room-temperature. In CZT, however, the hole collection efficiency is substantially less than 100% owing to its low hole-mobility. Therefore the detector signal is suppressed depending on the distance of ionization from the anode. In particular, gamma-rays interact with the detector at random, which result in asymmetric pulse-height distribution. Among the radiation transport codes available up to now, other than PHITS which can consider symmetric gaussian distribution, any codes did not have functions to consider arbitrary response functions. On the other hand, Melechankovski et al proposed a function form that can reproduce the pulse-height spectrum of CZT detectors. In this study, the pulse-height spectra of a 500 mm CZT detector exposed to gamma rays from 59 keV (
Am) to 1332 keV (
Co) was measured and compared with the energy deposition spectrum calculated PHITS with incorporating the Melechankovski's CZT detector response formula. The comparison showed satisfactory agreement between the calculated and measured pulse-height distribution featured by the gaussian peak shape and exponential decline in the lower energy side. This new function enables experimental design considering realistic detector performance as well as detector system design considering detector response. The arbitrary detector response function was incorporated to PHITS Ver.3.10 and later.
Makii, Hiroyuki; Nishio, Katsuhisa; Hirose, Kentaro; Orlandi, R.; Lguillon, R.; Ogawa, Tatsuhiko; Soldner, T.*; K
ster, U.*; Pollitt, A.*; Hambsch, F.-J.*; et al.
Physical Review C, 100(4), p.044610_1 - 044610_7, 2019/10
Times Cited Count:12 Percentile:72.85(Physics, Nuclear)Constantini, J.-M.*; Ogawa, Tatsuhiko; Bhuian, A. S. I.*; Yasuda, Kazuhiro*
Journal of Luminescence, 208, p.108 - 118, 2019/04
Times Cited Count:5 Percentile:33.18(Optics)Cathodo-luminescence is used for detection of lattice defects, in particular oxygen vacancies in ceramics induced by electrons. However, how oxygen vacancy production efficiency depends on sample temperature, incoming electron flux, and electron energy was not clear. In this study, oxygen vacancies were made in the specimens of AlO
, ZrO
:Y(Yttrium stabilized zirconia), MgAl
O
, and TiO
by irradiation of 400-1250keV electrons and the cathodoluminescence from thus induced vacancies were observed by photo-fiber probe combined with CCD. As the result, the dependence of luminescence intensity on specimen temperature depends on the carrier trapping frequency and luminescence efficiency while luminescence center production/annihilation speed determines the dependency on the incoming electron flux. Moreover, radiation transport calculation conducted by the particle transport simulation code PHITS indicates that the number of electrons above the defect production threshold energy is vital to explain incoming electron energy dependence.
Makii, Hiroyuki; Nishio, Katsuhisa; Hirose, Kentaro; Orlandi, R.; Lguillon, R.*; Ogawa, Tatsuhiko; Soldner, T.*; Hambsch, F.-J.*; A
che, M.*; Astier, A.*; et al.
Nuclear Instruments and Methods in Physics Research A, 906, p.88 - 96, 2018/10
Times Cited Count:3 Percentile:26.77(Instruments & Instrumentation)We have developed a new setup to measure prompt fission -ray spectra in neutron induced fission up to energies sufficient to reveal the structure associated with giant dipole resonances of fission fragments. The setup consists of multi-wire proportional counters, to detect both fission fragments in coincidence, and two large volume (101.6 mm in diameter and 127.0 mm in length) LaBr
(Ce) scintillators, to measure the
-rays. The setup was used to obtain the prompt fission
-ray spectrum for thermal neutron induced fission of
U at the PF1B cold-neutron beam facility of the Institut Laue-Langevin, Grenoble, France. We have successfully measured the
-ray spectrum up to energies of about 20 MeV, what extends the currently known
-ray spectrum limit to higher energies by approximately a factor of two.
Makii, Hiroyuki; Nishio, Katsuhisa; Hirose, Kentaro; Orlandi, R.; Lguillon, R.; Ogawa, Tatsuhiko; Soldner, T.*; Hambsch, F.-J.*; Astier, A.*; Pollitt, A.*; et al.
EPJ Web of Conferences, 146, p.04036_1 - 04036_4, 2017/09
Times Cited Count:4 Percentile:89.07(Nuclear Science & Technology)The measurement of the prompt fission -ray spectrum (PFGS) is quite important to study the de-excitation process of neutron-rich fission fragments as well as to generate data required to design a generation-IV reactors. The PFGS measured for spontaneous fission of
Cf shows a broad hump at energies more than 8 MeV. This is interpreted as a giant dipole resonance (GDR) of the fragments centered around 15 MeV. To understand how the GDR is populated in the fission process, one needs to measure the PFGS for the reactions with the mass yields different from the spontaneous fission of
Cf, such as (n,f). The measurements of the PFGS for (n,f), however, are limited less than 9 MeV even in the recent experiment. This prompts us to make a new measurement to extend the know PFGS up to 20 MeV. The measurement has been carried out at the PF1B beam line of Institut Laue-Langevin. In this contribution we will present the results obtained the measurement.
Watanabe, H.*; Lorusso, G.*; Nishimura, Shunji*; Otsuka, T.*; Ogawa, K.*; Xu, Z. Y.*; Sumikama, Toshiyuki*; Sderstr
m, P.-A.*; Doornenbal, P.*; Li, Z.*; et al.
Physical Review Letters, 113(4), p.042502_1 - 042502_6, 2014/07
Times Cited Count:25 Percentile:76.50(Physics, 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:32 Percentile:74.89(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:191 Percentile:99.42(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:55.04(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:180 Percentile:98.41(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.
Ishii, Tetsuro; Makii, Hiroyuki*; Asai, Masato; Tsukada, Kazuaki; Toyoshima, Atsushi; Matsuda, Makoto; Makishima, Akiyasu*; Shigematsu, Soichiro*; Kaneko, Junichi*; Shizuma, Toshiyuki; et al.
Physical Review C, 78(5), p.054309_1 - 054309_11, 2008/11
Times Cited Count:16 Percentile:67.70(Physics, Nuclear)Ishii, Tetsuro; Makii, Hiroyuki; Asai, Masato; Koura, Hiroyuki; Shigematsu, Soichiro*; Tsukada, Kazuaki; Toyoshima, Atsushi; Matsuda, Makoto; Makishima, Akiyasu*; Shizuma, Toshiyuki; et al.
Nuclear Physics A, 805(1-4), p.257 - 259, 2008/06
no abstracts in English
Ishii, Tetsuro; Shigematsu, Soichiro*; Makii, Hiroyuki; Asai, Masato; Tsukada, Kazuaki; Toyoshima, Atsushi; Matsuda, Makoto; Makishima, Akiyasu*; Shizuma, Toshiyuki; Kaneko, Junichi*; et al.
Physics of Atomic Nuclei, 70(8), p.1457 - 1461, 2007/08
Times Cited Count:11 Percentile:60.98(Physics, Nuclear)We have measured deexcitation rays in the neutron-rich nuclei of
U,
Pu and
Cm. These nuclei were produced by the (
O,
O) two-neutron transfer reactions with a 200, 162 and 162 MeV
O beams and a
U,
Pu and
Cm targets, respectively, using the tandem accelerator at Tokai, Japan. The
rays in residual nuclei were measured by taking coincidence with scattering particles using Si
-
detectors. We have identified
rays in
U,
Pu and
Cm by selecting the kinetic energies of
O particles which correspond to the excitation energies in these nuclei below their neutron separation energies. The ground-state bands of
U,
Pu and
Cm were established up to 12
states and the
octupole band of
U was established up to 9
state. Because the deformations of these nuclei are well developed, the moments of inertia reflect the pairing gap, which is expected to be smaller, resulting in a larger moment of inertia, at the deformed shell closure. We have found that the moment of inertia of the ground-state band of
Cm
is considerably larger than that of
Cm
. This fact supports the existence of the deformed subshell closure at
in Cm isotopes. On the other hand, the moment of inertia of
Pu
was found to be smaller than that of
Pu
, which suggests that the deformed subshell closure at
weakens or disappears in Pu isotopes. These results are consistent with the prediction by a cranking model calculation.
Ishii, Tetsuro; Makii, Hiroyuki; Asai, Masato; Koura, Hiroyuki; Shigematsu, Soichiro*; Tsukada, Kazuaki; Toyoshima, Atsushi; Matsuda, Makoto; Makishima, Akiyasu*; Kaneko, Junichi*; et al.
Physical Review C, 76(1), p.011303_1 - 011303_5, 2007/07
Times Cited Count:15 Percentile:68.97(Physics, Nuclear)The ground-state bands of the neutron-rich Th and
U nuclei were established up to spin 10 and 8, respectively, by in-beam
-ray spectroscopy using the (
O,
Ne) two-proton pickup reaction with a
U and a
Pu target. Deexcitation
rays in
Th and
U were identified by selecting the kinetic energies of
Ne using Si
-
detectors. The excitation energies of the first 2
states in U and Pu isotopes have local minima at
, suggesting the possibility that nuclei with
have a spherical shell closure of
. Calculation using the Koura-Yamada single-particle potential gives an energy gap of 1.8 MeV at
for
U.
Ishii, Tetsuro; Shigematsu, Soichiro; Makii, Hiroyuki; Asai, Masato; Tsukada, Kazuaki; Toyoshima, Atsushi; Matsuda, Makoto; Makishima, Akiyasu*; Shizuma, Toshiyuki; Kaneko, Junichi*; et al.
Journal of the Physical Society of Japan, 75(4), p.043201_1 - 043201_4, 2006/04
Times Cited Count:19 Percentile:67.86(Physics, Multidisciplinary)The ground-state band of the neutron-rich transuranium nucleus Cm was established up to spin 12 by in-beam
-ray spectroscopy using the two-neutron-transfer reaction with a
Cm target and a 162 MeV
O beam. Deexcitation
rays in
Cm were identified by selecting the kinetic energies of
O particles with Si
-
detectors. The moment of inertia of
Cm
is considerably smaller than that of
Cm
, which supports the existence of the deformed subshell closure at
in Cm isotopes.
Ishii, Tetsuro; Shigematsu, Soichiro; Asai, Masato; Makishima, Akiyasu*; Matsuda, Makoto; Kaneko, Junichi*; Hossain, I.*; Ichikawa, Shinichi; Kono, Toshiyuki*; Ogawa, Masao*
Physical Review C, 72(2), p.021301_1 - 021301_5, 2005/08
Times Cited Count:20 Percentile:75.78(Physics, Nuclear)In the two-neutron-transfer reaction of a 200-MeV O beam with a
U target, deexcitation
rays in a neutron-rich nucleus of
U were measured. The
rays in
U were identified by taking coincidence with
O, using Si
-
detectors. The kinetic energies of
O particles allowed us to select the excitation energies of
U below the neutron separation energy. The ground-state band and the
octupole band of
U were established up to 12
and 9
, respectively. The octupole-band head of
U is higher than those of
U by about a hundred keV, suggesting that a secondary maximum of octupole correlations exists at
in U isotopes.
Pinard, J.*; Duong, H. T.*; Marescaux, D.*; Stroke, H. H.*; Redi, O.*; Gustafsson, M.*; Nilsson, T.*; Matsuki, S.*; Kishimoto, Yasuaki*; Kominato, K.*; et al.
Nuclear Physics A, 753(1-2), p.3 - 12, 2005/05
Times Cited Count:4 Percentile:35.56(Physics, Nuclear)The hfs separation of
Cs(
m) in the 6s
S
ground state was obtained in a precision measurement near zero magnetic field by means of atomic beam magnetic resonance with laser optical pumping on-line with the CERN-PSB-ISOLDE mass separator. The result,
MHz, corrects significantly a previous published value from a high-field experiment. With our result, the precision of the nuclear magnetic moment,
Cs)
, is now limited by the influence of extended nuclear structure on the hfs (the Bohr-Weisskopf effect).