Measurement of Neutron Capture Gamma-ray Spectrum of Natural Gold in the keV Energy Region

Jae Hong Lee,Samyol Lee,Sangbock Lee,Junhaeng Lee,Gyehwan Jin 한국방사선학회 2007 한국방사선학회 논문지 Vol.1 No.1

keV-neutron capture gamma-ray spectrum of 197Au(natural gold) sample have been measured in neutron energy range from 10 to 90 keV using the 3-MV pelletron accelerator of the Research Laboratory for Nuclear Reactors at the Tokyo Institute of Technology. Pulsed keV neutrons were produced from the 7Li(p,n)7Be reaction by bombarding on the 7Li target with the 1.5-ns bunched proton beam. The incident neutron spectrum on the Au sample was measured by a 6Li-glass scintillation detector and TOF method. Capture gamma-rays from Au sample were measured by anti-Compton NaI(TI) spectrometer. Five average neutron energy regions were selected to obtain the neutron capture spectrum. Several gamma-ray peaks in the spectrum were found in the present experiment. 동경공업대학교의 3MV 펠레트론가속기를 사용하여 10에서 90keV 영역에 대하여 197 Au의 중성자포획 스펙트럼을 측정하였다. 중성자 펄스빔은 7Li(p,n)7 Be반응을 통하여 발생되었다. 사용되어진 양성자 빔 의 폭은 1.5-ns였다. 금 시료에 입사된 중성자의 에너지 스펙트럼은 6 Li-glass 섬광검출기의 중성자 비행 시간법을 사용하여 측정하였다. 금 시료의 중성자포획에 의해서 발생된 감마선은 anti-Compton NaI(TI) 검출장비를 사용하여 측정되었다. 본 연구에서는 5개의 중성자 에너지 역영을 선택했고, 각각의 에너지 영역에서 얻어진 감마선파고스펙트럼을 표시하였다. 본 연구에서 얻어진 스펙트럼은 처음으로 얻어진 결과이며, 중성자 결합에너지부근에 몇 개의 천이 피크가 보인다.

Estimation of Neutron Absorption Ratio of Energy Dependent Function for ¹⁵⁷Gd in Energy Region from 0.003 to 100 eV by MCNP-4B Code

Samyol Lee 한국방사선학회 2009 한국방사선학회 논문지 Vol.3 No.3

Gd-157 material has very large neutron capture cross section in the thermal region. So it is very useful to shield material for thermal neutrons. Futhermore, in the neutron capture experiment and calculation, the neutron absorption and scattering are very important. Especially these effects are conspicuous in the resonance energy region and below the thermal energy region. In the case of very narrow resonance, the effect of scattering is to be more considerable factor. In the present study, we obtained energy dependent neutron absorption ratios of natural indium in energy region from 0.003 to 100 keV by MCNP-4B Code. The coefficients for neutron absorption was calculated for circular type and 1 ㎜ thickness. In the lower energy region, neutron absorption is larger than higher region, because of large capture cross section (1/v). Furthermore it seems very different neutron absorption in the large resonance energy region. These results are very useful to decide the thickness of sample and shielding materials.

Measurement of Branching Ratio for broad 27-keV Resonance of 19F(n,g)20F Reaction by using Time-of-flight Method with Anti-Compton NaI(Tl) Spectrometer

Samyol Lee 한국방사선학회 2008 한국방사선학회 논문지 Vol.2 No.1

The neutron capture spectrum for the light nuclide was very useful to study the nuclear structure. In the present study, the capture gamma-ray from the 27-keV resonance of 19F(n,g)20F reaction were measured with an anti-Compton NaI(Tl) spectrometer and the 3-MV Pelletron accelerator of the Research Laboratory for Nuclear Reactors at the Tokyo institute of technology. A neutron Time-of-Flight method was adopted with a 1.5 ns pulsed neutron source by the 7Li(p,n)7Be reaction. In the present experiment, a Teflon((CF2)n) sample was used The sample was disk with a diameter of 90mm. The thickness of sample was determined so that reasonable counting rates could be obtained and the correction was not so large for the self-shielding and multiple scattering of neutrons in the sample, and was 5mm. The primary gamma-ray transitions were compared with previous measurement of Kenny.

A Study on Measurement of Gamma-ray Spectrum for the Natural Tungsten nuclear reaction by using KOMAC proton Linear Accelerator

Samyol Lee(이삼열) 한국방사선학회 2018 한국방사선학회 논문지 Vol.12 No.2

The measurement of gamma-ray spectrum of nat W(p,xn) reaction with natural tungsten were performed by using a high energy proton generated from a 100-MeV proton linear accelerator of the Korea Multi-purpose Accelerator Complex (KOMAC). Gamma rays generated by various nuclides generated through the nuclide were measured using a gamma-ray spectroscopy system composed of HPGe detector. A gamma-ray standard source was used for energy calibration and efficiency measurement of the detector. Analysis of the gamma rays observed in the measured spectra showed that the radionuclides produced were 167 Re, 178 Re, 179 Re, 180 Re, 181 Re, 182 Re, 184 Re, 172 Ta, 174 Ta, 178 Ta, 182 Ta, 184 Ta, 175 W, 176 W, 177 W and 179 W. Nuclides were generated. The results of this study will be applied to nuclear fusion, astrophysics, and nuclear medicine applications in the future. 양성자가속기연구센터(KOMAC)의 100-MeV 양성자 선형가속기에서 생성된 고에너지 양성자를 사용하여 천연 텅스텐과 핵반응을 일으켰다. 핵반응을 통해 생성된 다양한 핵종으로 부터의 감마선은 HPGe 검출기 감마선 분광시스템을 사용하여 측정하였다. 감마선 표준선원은 에너지 교정 및 검출기의 효율 측정에 사용 되었다. 측정된 스펙트럼에서 관찰된 감마선을 분석한 결과 방사성 핵종은 167 Re, 178 Re, 179 Re, 180 Re, 181 Re, 182 Re, 184 Re, 172 Ta, 174 Ta, 178 Ta, 182 Ta, 184 Ta, 175 W, 176 W, 177 W 및 179 W 으로 총 16 종류의 핵종이 생성되었다. 이 연구의 결과는 미래의 핵융합, 천체 물리학 및 핵의학 응용 분야에 적용될 것으로 생각된다.

Estimation of Neutron Absorption Ratio of Energy Dependent Function for ¹⁵⁷Gd in Energy Region from 0.003 to 100 eV by MCNP-4B Code

( Samyol Lee ) 한국방사선학회 2009 한국방사선학회 논문지 Vol.3 No.3

Gd-157 material has very large neutron capture cross section in the thermal region. So it is very useful to shield material for thermal neutrons. Futhermore, in the neutron capture experiment and calculation, the neutron absorption and scattering are very important. Especially these effects are conspicuous in the resonance energy region and below the thermal energy region. In the case of very narrow resonance, the effect of scattering is to be more considerable factor. In the present study, we obtained energy dependent neutron absorption ratios of natural indium in energy region from 0.003 to 100 keV by MCNP-4B Code. The coefficients for neutron absorption was calculated for circular type and 1 mm thickness. In the lower energy region, neutron absorption is larger than higher region, because of large capture cross section (1/v). Furthermore it seems very different neutron absorption in the large resonance energy region. These results are very useful to decide the thickness of sample and shielding materials

Resonance Integral of Neptunium(²³⁷Np) from Energy Dependent Differential Neutron Capture Cross-Section by Using the Linac TOF Method and C₆D₆ Scintillation Spectrometer

Samyol Lee 한국방사선학회 2011 한국방사선학회 논문지 Vol.5 No.4

²³⁷Np is very important material in the fission products of nuclear reactors. Resonance integral(RI) tests of this material is necessary to check between the experiments and the evaluated data. Such feedback to the evaluated data is very important to correct data and improve of codes. The RI for the ²³⁷Np(n,γ)²³⁸Np reaction were measured by using the 46-MeV electron linear accelerator (linac) at the Research Reactor Institute, Kyoto University (KURRI). The measurement was performed in the energy region from 0.005 eV and 10 keV. RI obtained as 804.7 barns, compared with those of the evaluated data in JENDL-4.0 and Mughabghab.

Calculation of Energy Dependent Neutron Correction Coefficient Ratios of Natural Rhodium in Energy Region from 0.003 to 100 eV

Samyol Lee 한국방사선학회 2008 한국방사선학회 논문지 Vol.2 No.3

In the neutron capture experiment and calculation, the neutron absorption and scattering are very important. Especially these effects are conspicuous in the resonance energy region and below the thermal energy region. In the present study, we obtained energy dependent neutron absorption ratios of natural rhodium in energy region from 0.003 to 100 eV by MCNP-4B Code. The coefficients for neutron absorption was calculated for several types of thickness. In the lower energy region, neutron absorption is larger than higher region, because of large capture cross section (1/v). Furthermore it seems very different neutron absorption in the large resonance energy region. These results are very useful to decide the thickness of sample and shielding materials.

Estimation of Neutron Absorption Ratio of Energy Dependent Function for (^157)Gd in Energy Region from 0.003 to 100 eV by MCNP-4B Code

Samyol Lee 한국방사선학회 2009 한국방사선학회 논문지 Vol.3 No.3

Gd-157 material has very large neutron capture cross section in the thermal region. So it is very useful to shield material for thermal neutrons. Futhermore, in the neutron capture experiment and calculation, the neutron absorption and scattering are very important. Especially these effects are conspicuous in the resonance energy region and below the thermal energy region. In the case of very narrow resonance, the effect of scattering is to be more considerable factor. In the present study, we obtained energy dependent neutron absorption ratios of natural indium in energy region from 0.003 to 100 keV by MCNP-4B Code. The coefficients for neutron absorption was calculated for circular type and 1 mm thickness. In the lower energy region, neutron absorption is larger than higher region, because of large capture cross section (1/v). Furthermore it seems very different neutron absorption in the large resonance energy region. These results are very useful to decide the thickness of sample and shielding materials.

양성자 가속기 연구센터의 100 MeV 양성자 가속기를 이용한 208Pb(p,x)Tl의 상대 단면적 측정

이지은(Lee Jieun),윤정란(Yoon Jungran),노태익(Ro Taeik),이삼열(Lee Samyol) 한국방사선학회 2014 한국방사선학회 학술대회 논문집 Vol.2014 No.추계

중선화 포획을 이용한 핵자료는 다양한 방법으로 구축되고 있으나 양성자 핵반응에 대한 핵자료는 핵반응 연구, 중성자 발생, 원자력 재료 개발 등 원자력분야에서 원자핵을 다룰 수 있는 중요한 역할을 담당하고 있음에도 불구하고 양성자 각속기의 제약으로 인하여 그 결과가 양적인 면이나 질적인 면에서 부족한 것이 현실이다. 그러나 최근 양성자를 이용한 각종시설의 증가(핵융합로, 우주선, 인공위성 등)로 양성자 핵반응에 대한 핵자료의 필요성이 매우 증가되고 있는 현실이다. 본 연구에서는 경주에 소재하고 있는 양성자 가속기 연구센터의 100MeV 양성자 가속기를 이용하여 천연 Pb의 (p,x)반응에 대하여 지발 감마선의 에너지 스펙트럼을 HPGe 검출기를 이용하여 측정하고, 각각의 반응에 대한 분기비를 측정하여 상대단면적을 측정하였다. 측정된 결과는 Evaluated Nuclear Data File(ENDF)와 Experimental Nuclear Reation Data(EXFOR)에 등록되어 있는 결과들을 이용하여 비교 분석 하였다. generator, and accelerator. Nuclear data using proton nuclear reaction plays an important role that can handle the study of nuclear reaction, neutron generation, and nuclear power material development, the nuclei in the nuclear field. However, it is a reality due to limitations of proton acceleration system, is the missing in qualitative terms and quantitative aspects of the results. It is a real need for nuclear reaction data of the proton is that of has been increasing very (nuclear fusion reactor, cosmic-ray, and satellite) to the increase of various facilities using proton recently. In this study, we have measured the energy spectrum of delayed gamma-ray (p,x) for the reaction of Natural Pb Target by using a HPGe spectrometer system and the 100 MeV proton accelerator of Korea Multi-Purpose Accelerator Complex which is located in the Gyeongju. Then, to measure the relative cross-section by measuring branching ratio reaction of each. The results were compared with analysis results of Evaluated Nuclear Data File(ENDF/B-VII) and Experimental Nuclear Reaction Data(EXFOR).

100 MeV 양성자를 이용한 natW(p,nx)176Re 핵반응의 상대 핵반응단면적 측정에 대한 연구

이삼열(Samyol Lee) 한국방사선학회 2021 한국방사선학회 논문지 Vol.15 No.2

본 연구는 한국원자력연구원에서 보유하고 있는 100 MeV 선형가속기를 사용하여 천연텅스텐과의 핵반응으로 부터 발생시켜 발생되는 감마선을 측정하여 natW(p,nx)176Re 핵반응에 대한 상대핵반응단면적을 도출하였다. 일반적으로 반감기가 짧은 동위원소에 대한 연구는 항상 짧은 시간 내에 방사능의 강도가 급격하게 작아지는 경향을 보이기 때문에 측정자체가 매우 어려운 것이 현실이다. 특히 176Re의 경우는 반감기가 5.3 분으로 상대적으로 매우 짧은 방사성핵종 중의 하나이다. 본 연구에서는 이런 짧은 반감기를 가지는 176Re 동위원소로부터 발생되는 109.08 keV 감마선을 고순도 Ge검출기를 이용하여 측정하였다. 얻어진 상대 측정값들은 1967년에 Richard G.에 의해 발표된 8 ~ 14 MeV 양성자에너지 영역에서의 결과와 이를 기반으로 계산에 의한 핵반응단면적에 대한 평가한 2019년 A. J. Koning의 결과인 TENDL-2019값과 비교분석하였다. 이 연구의 결과는 미래의 에너지원으로 알려져 있는 핵융합로의 설계, 천체 물리학, 핵의학 및 양성자치료 분야에 요긴하게 활용될 것으로 생각된다. This study derives the relative cross-section for the natW(p,nx)176Re nuclear reaction by measuring the gamma rays generated from the nuclear reaction with natural tungsten using a 100 MeV linear accelerator of the Korea Multi-purpose Accelerator Complex in the Korea Atomic Energy Research Institute. In general, research on isotopes with a short half-life always shows a tendency that the intensity of radioactivity decreases rapidly within a short period of time, making it very difficult to measure itself. In particular, 176Re is one of the relatively short radionuclides with a half-life of 5.3 minutes. In this study, 109.08 keV gamma rays generated from the 176Re isotope having such a short half-life were measured using a high-purity Ge detector(HPGe detector). The obtained relative measurements were the results in the 8 to 14 MeV proton energy domain published by Richard G. in 1967, and the TENDL-2019 value, which was the result of A. J. Koning in 2019, which evaluated the nuclear reaction cross-section by calculation based on this comparative analysis was performed. The results of this study are expected to be usefully applied to the design of nuclear fusion reactor which is known as future energy sources, elements ratio for the nuclear synthesis of astrophysics.