• The Journal of the Korea Contents Association
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• v.5 no.5
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• pp.133-139
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• 2005

The neutron capture cross section of $^{99}Tc$ has been measured relative to the $^{10}B(n,\gamma)$ standard cross section by the neutron time-of-flight(TOF) method in the energy range of 0.007 eV to 47 keV using a 46-MeV electron linear accelerator(linac) at the Research Reactor. Institute, Kyoto University(KURRI). In order to experimentally prove the result obtained, the supplementary cross section measurement has been made from 0.3 eV to 1 keV using the Kyoto University Lead stowing-down spectrometer (KULS) coupling to the linac. The relative measurement by the TOF method has been normalized to the reference value(20.01 b) at 0.0253 eV and the KULS measurement to that by the TOF method. The existing experimental data and the evaluated capture cross sections in ENDF/B-VI, JENDL-3.2, and JEF-2.2 have been compared with the current measurements by the linac TOF and the KULS experiments.

• Nuclear Engineering and Technology
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• v.34 no.2
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• pp.154-164
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• 2002

Neutron cross section data on Dy-160, Dy-161, Dy-162, Dy-163 and Dy-164 were calculated and evaluated in the energy range of 1 keV to 20 MeV using a spherical optical model, statistical model and pre-equilibrium model. The energy dependent optical model potential parameters were obtained based on the recent experimental data. The width fluctuation correction in Hauser-Feshbach particle decay and the quantum mechanical approach in pre-equilibrium analysis were introduced and gave a better cross section calculation in EMPIRE-II. The total, elastic scattering and threshold reaction cross sections were evaluated and compared with the evaluated files. The model calculated (n, tot), (n, ${\gamma}$) and (n, p) cross sections were in good agreement with the experimental data in the measured energy range. The results will be applied to ENDF/B-VI for data improvement.

• Proceedings of the Korean Nuclear Society Conference
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• 1997.10a
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• pp.185-190
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• 1997

고속로 검증실험의 2차원 상세해석을 MATXS형 라이브러리와 TWODANT를 이용하여 수행하였다. 80군자료를 2차원 coarse mesh 계산으로 생산된 중성자속을 가중함수로하여 25군으로 축약하고, P$_3$S$_{8}$, 2차원 R-Z모델로 임계도 및 중심반응률비를 계산하여 실험값과 비교하였다. 이 과정에서 ENDF/B-VI$_3$, JEF-2.2 그리고 JENDL-3.2 라이브러리를 상호 비교, 검토하였다.

• Proceedings of the Korean Nuclear Society Conference
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• 1996.05a
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• pp.125-130
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• 1996

최근 고리원자력 4호기 압력용기에 대한 제 3차 감시시험$^{(1)}$ 이 수행되었고 그 과정 중 측정된 시편에서의 반응률을 근거로 선량분석을 수행하였다. ENDF/B-VI를 근거로 만들어진BUGLE93$^{(2)}$ 라이브러리를 사용하여 각분할코드인 DORT version 2.7.3$^{(3)}$ 를 이용한 forward 및 adjoint 수송 계산 결과와 측정된 반응률을 결합하여 고리 4호기 원자로의 감시시편 X를 대상으로 1 MeV이상의 중성자속, 0.1 MeV 이상의 중성자속 및 dpa(displacement per atom)를 계산하여 측정치와 계산치를 비교하였다.

• Nuclear Engineering and Technology
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• v.48 no.3
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• pp.642-649
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• 2016

Important safety parameters such as the fuel temperature coefficient (FTC) and the power coefficient of reactivity (PCR) of the CANada Deuterium Uranium (CANDU-6) reactor have been evaluated using the Monte Carlo method. For accurate analysis of the parameters, the Doppler broadening rejection correction scheme was implemented in the MCNPX code to account for the thermal motion of the heavy uranium-238 nucleus in the neutron-U scattering reactions. In this work, a standard fuel lattice has been modeled and the fuel is depleted using MCNPX. The FTC value is evaluated for several burnup points including the mid-burnup representing a near-equilibrium core. The Doppler effect has been evaluated using several cross-section libraries such as ENDF/B-VI.8, ENDF/B-VII.0, JEFF-3.1.1, and JENDL-4.0. The PCR value is also evaluated at mid-burnup conditions to characterize the safety features of an equilibrium CANDU-6 reactor. To improve the reliability of the Monte Carlo calculations, we considered a huge number of neutron histories in this work and the standard deviation of the k-infinity values is only 0.5-1 pcm.

• Journal of the Korean Society of Radiology
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• v.7 no.3
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• pp.245-249
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• 2013

Neutron sources from photonuclear reaction with 46-MeV electron linear accelerator at Research Reactor Institute, Kyoto University used for resonance energy measurement of natural tantalum. BGO($Bi_4Ge_3O_{12}$) scintillation detectors used for measurement of the prompt gamma ray from the natural tantalum sample. The BGO spectrometer was composed geometrically as total energy absorption detector. The electric signal from the spectrometer was analyzed for TOF(Time-of-Flight) spectrum which is used identification of neutron capture resonance energy. In this study, the neutron energy region is from 1 to 200 eV, because of strong X-ray effect produced photonuclear reaction in Ta target, the measurement was performed to below 1 keV energy region. The resonance energy was compared with the evaluated values(ENDF/B-VI, Mughabghab). All of the resonances from 4.28 ~ 200 eV were seen in the present measurement except 144.3 eV resonance.

• Proceedings of the Korean Nuclear Society Conference
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• 1998.05b
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• pp.771-776
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• 1998

TORT is employed for fast neutron fluence calculation at the reactor pressure vessel. KORI Unit 1 reactor at cycle 1 is modeled for this calculation. Three-dimensional cycle averaged assembly power distributions for KORI Vnit 1 at cycle 1 are calculated by using the core physics code, NESTLE 5.0. The root mean square error is within 4.3% compared with NDR (Nuclear Design Report) far all burnup steps. The C/E (Calculated/Experimental) values for the in-vessel dosimeters distribute between 0.98 and 1.36. The most updated cross-section library. BUGLE-96 based on ENDF/B-VI is used for the neutron fluence calculation. The makimum fast neutron nun calculated on reactor pressure vessel for KORI Unit 1 operated for 411.41 effgctive full power days is 1.784x10$^{18}$ n/$\textrm{cm}^2$. The position of the maximum neutron fluence in RPV wall 1/4 T is nearby 60cm below the midplane at zero degree.

• Proceedings of the Korean Nuclear Society Conference
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• 1997.10a
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• pp.50-57
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• 1997

영광 2호기 9주기 노심을 대상으로 다양한 운전조건에서 노외계측기 weighting function을 계산하고 영향 인자들에 대한 민감도 분석을 수행하였다. Weighting function 계산은 2차원 각분할 수송코드인 DORT 2.8.14를 사용하였고 핵단면적 라이브러리는 ENDF/B-VI에 근거한 BUGLE93 라이브러리를 사용하였다. Weighting function은 축방향 weighting function(R-Z 모델)과 집합체별 weighting function(R- 모델)을 계산하였고, 민감도 분석에 사용한 인자는 출력준위, 연소도, 제어봉 삽입, 붕소농도이다. 민감도 분석결과 노외계측기 weighting function은 출력 준위에 민감하고 그외 모든 인자의 영향은 무시할 수 있을 만큼 작았다. 또한 출력분포와 weighting function으로부터 계산되는 단순노외계측기 교정법의 계측기반응상수는 출력준위와 연소도를 고려하여 생산해야함을 확인하였다.

• Proceedings of the Korea Contents Association Conference
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• 2004.11a
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• pp.495-500
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• 2004

The neutron capture cross section of $^{99}Tc$ has been measured relative to the $^{10}B$(n,g) standard cross section by the neutron time-of-flight(TOF) method in the energy range of 0.007 eV to 47keV using a 46-MeV electron linear accelerator(linac) at the Research Reactor Institute, Kyoto University(KURRI). In order to experimentally prove the result obtained, the supplementary cross section measurement has been made from 0.3 eV to 1 keV using the Kyoto University Lead slowing-down Spectrometer(KULS) coupling to the linac. The relative measurement by the TOF method has been normalized to the reference value(20.01 b) at 0.0253 eV and the KULS measurement to that by the TOF method. The existing experimental data and the evaluated capture cross sections in ENDF/B-VI, JENDL-3.2, and JEF-2.2 have been compared with the current measurements by the linac TOF and the KULS experiments. The energy dependency of the KULS data is close to that of the TOF data which are energy-broadened by the resolution function of the KULS.

• Nuclear Engineering and Technology
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• v.31 no.4
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• pp.401-407
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• 1999

We have performed two experiments in the fast critical assembly BFS to measure the effective delayed neutron fraction $\beta$$_{eff}$ values and compared the results to validate the $\beta$$_{eff}$ computation code, BETA-K. Measurements of $\beta$$_{eff}$ were carried out in a metallic plutonium core and a metallic uranium core with Cf$^{252}$ source pseudo-reactivity method. Fission integrals and correction factors, which were used to obtain the experimental $\beta$$_{eff}$ values, were calculated by using the LMR core design computation code system of KAERI. BETA-K has been developed consistently with the hexagonal Nodal Expansion Method (NEM) and it used delayed neutron data of ENDF/B-VI. By comparing the computed $\beta$$_{eff}$ values with the measured ones, we found that the results from BETA-K agreed with the experimental values within the experimental error bound.ror bound.