• Nuclear Engineering and Technology
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• v.17 no.1
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• pp.1-7
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• 1985

Non-destructive gamma-ray spectrometry was carried out on the spent PWR fuel assemblies at the spent fuel pool of reactor-site. Attention was focused on the determination of burnup distribution and cooling time. For the measurement of burnup distribution, the concentration ratio of $^{134}$ Cs$^{137}$ Cs was used and the results showed these ratios varied with the positions of assemblies in the core during their irradiation. For the measurement of cooling time, $^{144}$ Ce$^{137}$ Cs was used and the results were agreed considerably well with the operator declared cooling time.

• Proceedings of the Korean Nuclear Society Conference
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• 1998.05b
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• pp.509-514
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• 1998

ORIGEN-S 전산코드로 계산된 가압경수로(PWR)사용후핵연료 내에 존재하는 방사성핵종비 $^{134}$ Cs/$^{137}$Cs 및 $^{154}$ Eu/$^{137}$Cs 를 감마선 분광실험으로 측정한 값과 비교하여 핵연료의 연소도를 결정하였다. 고리 1호기 및 2호기 사용후핵연료봉에 대한 감마선 분광실험을 한국원자력연구소 조사재시험시설(IMEF)과 조사후시험시설(PIEF)의 시험기기 및 장치를 이용하여 수행하고 이 결과로부터 $^{134}$ Cs/$^{137}$Cs 와 $^{154}$ Eu/$^{137}$Cs 의 핵종비를 측정하였다. 이와 별도로 사용후핵연료의 연소도, 냉각시간, 초기농축도등에 따른 $^{134}$ Cs/$^{137}$Cs 와 $^{154}$ Eu/$^{137}$Cs의 핵종비를 ORIGEN-S 코드로 계산을 하였으며, 이 핵종비와 연소도 사이의 관계를 회귀분석하여 2차 다항식 함수로 유도하였다 이관계식과 감마선 분광실험으로 측정한 $^{134}$ Cs/$^{137}$Cs와 $^{154}$ Eu/$^{137}$Cs 의 핵종비를 이용하여 각각의 연소도를 결정할 수 있었다.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.4
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• pp.193-200
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• 2014

In this paper, the prototype of one-channel gamma-ray spectroscope for automatic radiopharmaceutical systhesis system was designed and characterized. The prototype employed CZT (CdZnTe) spear detector for gamma-ray detection and employed analog-type signal processing method. A radioactive sample Co-60 was used for measuring performance of the gamma-ray spectroscope and energy spectrum is gained with bandwidth of 1173keV. The analog board is made up of SF (shaping filter) and PHA (peak and hold amplifier) for shaping CZT output signal appropriately and ADC (analog to digital converter) and FPGA (field programmable gate array) for drawing gamma-ray spectrum by counting the digitalized gamma-ray signal data.

• Journal of Radiation Protection and Research
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• v.38 no.2
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• pp.119-123
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• 2013

A simple laboratory-made radioactive source to check the integrity of a gamma spectrometry system with HPGe detector was developed. The check source consists of radium-riched soil which was ground in size of less than 0.154mm and contained in air tight cylinderical vial, and provides photons with 12 distinct energies. The spectra of the check source were measured once a month during one year, analyzed the charactreictics of their peaks. When the gamma spectrometry system was in normal state, the areas and FWHMs of the gamma rays with more than 3% gamma emission rate in radium and its decay products was constant within standard deviation 2% and 3%, respectively, except 77 keV peak. And it was found that this check source can play a sufficient role to check the integrity of a gamma spectrometry system using 10 peaks in the range of 77 to 2202 keV.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2004.06a
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• pp.407-417
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• 2004

This study is to verify radiation detection method by using $\alpha$-spectroscopy and ${\gamma}$-spectroscopy for concretes and components which will be generated during the decommissioning of the uranium conversion plant. Components and inside walls of the building were contaminated with natural uranium materials. Some parts of the stainless steel pipes and concretes of the walls were sampled and analyzed their alpha and gamma activities respectively. Alpha and gamma activities are well matched each other in the range of high activity region to 0.01 Bq/g and gamma activities are over estimated comparing alpha activities corresponded in below 0.005 Bq/g region for the natural uranium of AUC sample. The $^{238}U$ originated from natural products of conversion process could be distinguished by measuring $^{214}Pb$ or $^{214}Bi$ and $^{234}Th$ or $^{234m}Pa$. Uranium contaminations mainly are in the wall surface of the plant. Decontamination process of generating wastes which can be reached tp background level gamma activities measured by gamma spectroscopy can also be used to conservative assessment data.

• Journal of Radiation Protection and Research
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• v.40 no.2
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• pp.73-78
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• 2015

In this study, a scintillation detector was fabricated using a silicon photomultiplier (SiPM) and a Ce:GAGG scintillator single crystal, and its spectroscopic properties were compared with those of commercially available LYSO and CsI:Tl scintillators using ${\gamma}$-ray spectroscopy. The energy resolutions of the self-produced scintillation detector composed of the scintillator single crystal (volume: $3{\times}3{\times}20mm^3$) and SiPM (Photosensitive area: $3{\times}3mm^2$) for standard ${\gamma}$-ray sources, such as $^{133}Ba$, $^{22}Na$, $^{137}Cs$ and $^{60}Co$ were measured and compared. As a result, the energy resolutions of the proposed Ce:GAGG scintillation detector for g-rays, as measured using its spectroscopic properties, were found to be 13.5% for $^{133}Ba$ 0.356 MeV, 6.9% for $^{22}Na$ 0.511 MeV, 5.8% for $^{137}Cs$ 0.662 MeV and 2.3% for $^{60}Co$ 1.33 MeV.

• Analytical Science and Technology
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• v.14 no.3
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• pp.212-220
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• 2001

This study was performed to establish the analytical method of radium and radon in various environmental samples with the ${\gamma}$-ray spectrometry. The major problem in the measurements of low level ${\gamma}$-ray, such as environmental radioactivity, is the fluctuation of ${\gamma}$-ray background spectrum. To overcome this problem, a nitrogen gas was filled up in the detector chamber to reduce the background counts due to airborne radioactivities, i.e., $^{214}Pb$ and $^{214}Bi$, the daughters of $^{222}Rn$ in air. When nitrogen gas flowed around the detector, peak counts of ${\gamma}$-rays from the daughters of $^{222}Rn$ decreased about 80% below 1 MeV and about 20~50% above 1 MeV. The use of nitrogen purging results in approximately tenfold increment of sensitivity.

• Proceedings of the Korean Nuclear Society Conference
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• 1998.10a
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• pp.317-317
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• 1998

• Analytical Science and Technology
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• v.13 no.6
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• pp.743-750
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• 2000

For the ${\gamma}$-ray spectrometry analysis of radium and radon in environmental samples, plastic Marinelli beakers have been usually used. But, there are two problems; one is the increment of background by adsorption of airborne radon daughters on the plastic beaker, and other is the incompleteness of radioactive equilibrium by the loss of gaseous radon produced during the radioactive equilibrium process. In order to solve these problems, we made aluminium counting container, and investigated its characteristics. We investigated radioactive equilibrium process using the aluminium container. We found that both solid and liquid samples reached at radioactive equilibrium state in the aluminium container without loss of gaseous radon. By the use of the aluminium container, we established radon and radium analysis method of solid and liquid samples using gamma-ray spectrometry.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.12 no.2
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• pp.97-105
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• 2014

In the case of the direct measurement of $^{226}Ra$ using a HPGe gamma-ray spectrometer, the interference between gammarays with 186.21 keV of $^{226}Ra$ and 185.7 keV of $^{235}U$ should be corrected to calculate the net peak area in the energy spectrum. In general, it is very difficult to conduct peaks stripping with difference of about 0.5 keV, although a HPGe with the superior resolution is applied and the maximum channels is applied to the spectrometer. In this study, several interference correction techniques in the direct measurement were surveyed to evaluate the feasibility for the measurement of $^{226}Ra$ using the gamma-ray spectrometery. Applying the interference corrections to the analysis of raw materials and by-products, the method validation for the direct measurement of $^{226}Ra$ was conducted by evaluating the measurement uncertainty, linearity, and range. As a result, the optimum method of the interference correction was selected by comparing with the indirect measurement of which progenies of $^{226}Ra$, such as $^{214}Pb$ and $^{214}Bi$, were analyzed in the secular equilibrium state.