tailieunhanh - Improvement of the detection limit by radon background reduction method

This paper describes a simple method to reduce the radon background component applied in environmental studies using gamma spectrometry. The radon component can be reduced by introducing either nitrogen gas or clean air into the detector chamber in order to create a positive pressure and further minimize radon intrusion from outside. | Science & Technology Development, Vol 19, Improvement of the detection limit by radon background reduction method Tran Thien Thanh Chau Van Tao University of Science, VNU-HCM Laurent Ferreux Marie Christine Lépy CEA, LIST, Laboratoire National Henri Becquerel (LNE-LNHB) (Received on 3rdMarch 2016, accepted on 2th December 2016) ABSTRACT This paper describes a simple method to radon intrusion from outside. This method shows reduce the radon background component applied that we can minimize the influence of radon in environmental studies using gamma daughter background such as 214Pb, 214Bi and 210 spectrometry. The radon component can be Pb (from 238U), 212Pb, 212Bi and 208Tl (from 232 reduced by introducing either nitrogen gas or Th). By the way, the detection limit of the clean air into the detector chamber in order to gamma spectrometry is discussed. create a positive pressure and further minimize Keywords: gamma spectrometry, limit detection, background INTRODUCTION There are many efforts to the issues such as to look for the proper shielding materials for better detector housing and so on. Techniques developed so far for rare event research, dark matter search in particle and nuclear physics research are well known. In this research we would like to investigate the most suitable and sensitive technique for fixing the background origin in the materials. To improve the detection limits in low level activity measurements, the background has to be reduced as much as possible. The background spectrum of a germanium detector is due to a combination of different components such as environmental gamma radiation, radioactivity in the construction material of the detector, radio impurities in the shield, cosmic rays and radon gas. The first three contributions can be reduced drastically by means of a suitable passive shielding made of old or very low – activity lead and by a careful selection of materials Trang 126 surrounding the crystal. The .

• Hoá học
• Gamma spectrometry
• Limit detection
• Radon background reduction method
• Improvement of the detection limit
• Environmental studies
• Environmental studies using gamma spectrometry
• Nuclear engineering and technology
• Numerical evaluation of gamma radiation monitoring
• Gamma radiation monitoring
• Inherent stochastic properties
• BFGS training algorithm
• Airborne gamma ray spectrometry
• Nuclear site surveillance
• Master's thesis of Applied Science
• Master's thesis of Applied Physics
• Monte carlo modeling
• Gamma ray spectroscopy
• Lead shielding producing activation
• Implications for gamma ray spectrometry
• Intrinsic Variables
• Applied Gamma Ray Spectrometry
• Isomeric Transition
• Characteristic X Ray Excitation
• Beta Transitions
• HPGe gamma spetrometer
• Radionuclide depth distributions
• Full energy peak efficiency
• In Situ Object Counting Systems
• Gamma ray energies
• Hydrogel reinforced with bentonite
• Gamma irradiation for metal absorption
• Natural based sodium carboxymethyl cellulose
• Atomic absorption spectrometry
• Absorb metal ions
• Radiation measurements
• Scintillation gamma spectrometry
• Spectrum drift correction
• Dose rate measurement
• OSL dating
• Gamma ray spectrometry
• Dose rate calculation
• Radioactivity analyses
• Luminescence dating
• Efficiency calibration
• Environmental samples
• Monte Carlo simulation
• HPGe spectrometer
• Activity concentrations of 210Pb
• HPGe spectrometry
• Meteorological parameters
• Institute for Nuclear Science and Technology
• HPGe gamma ray spectrometry
• Nuclear energy
• Radiological characterisation
• D&D processes
• Dose rate measurements
• Total gamma measurements
• In situ gamma ray spectrometry
• báo cáo khoa học
• báo cáo y học
• công trình nghiên cứu về y học
• tài liệu về y học
• cách trình bày báo cáo
• Monte Carlo calculation
• Mathematics
• Physics
• Scientific reports
• scientific studies
• natural sciences
• Tạp chí khoa học
• Khoa học tự nhiên
• Activity concentration
• Radium Equivalent Activity
• Secular equilibrium
• Intrinsic efficiency calibration
• Efficiency calibration of a coaxial HPGe detector Marinelli beaker geometry
• 152Eu source prepared in epoxy matrix
• Efficiency transfer method
• In house source preparation
• Earth sciences
• Natural radioactivity
• Major and accessory minerals
• Wall rock granitoids
• Natural radionuclides
• HPGe detector
• Marinelli beaker
• ANGLE3 commercial software
• Trapped charge dating methods
• Beta particle emission
• Dilution analysis
• High resolution gamma spectrometry