Download or read book Characterization of Phoswich Well Detectors for Radioxenon Monitoring written by and published by . This book was released on 2007 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: Devices to measure the amount of radioactive xenon in the atmosphere have been installed in several locations around the world as part of the International Monitoring System to detect nuclear weapons testing. These devices extract small samples of xenon from large volumes of air and look for characteristic radioxenon isotopes emitting beta and gamma radiation in coincidence. To detect these coincidences, they currently employ a complex system of separate beta and gamma detectors which is very sensitive, but which requires careful calibration and gain matching of several detectors and photomultiplier tubes to achieve desired detection limits. An alternative to separate beta and gamma detectors is the use of a single phoswich detector in which beta-gamma coincidences are detected by pulse shape analysis. The phoswich detector consists of a plastic scintillator (absorbing betas) optically coupled to a CsI(Tl) scintillator (absorbing gammas) and thus requires only a single photomultiplier tube and electronics readout channel, greatly simplifying setup and calibration. In this paper, we present the results from an experimental evaluation of two phoswich well detector prototypes, including energy resolution, 2-D beta/gamma energy histograms from a variety of test sources, and background count rates. From these measurements, we derive detector properties such as coincidence detection efficiency, background rejection and the ability to separate beta only, gamma only, and coincidence events. We will further discuss setup and calibration procedures and compare them to those for existing detector systems.

Download or read book DESIGN OF A PHOSWICH WELL DETECTOR FOR RADIOXENON MONITORING written by William K. Warburton and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The network of monitoring stations established through the Comprehensive Nuclear-Test-Ban Treaty includes systems to detect radioactive xenon released into the atmosphere from nuclear weapons testing. One such monitoring system is the Automated Radio-xenon Sampler/Analyzer (ARSA) developed at Pacific Northwest National Laboratory. For high sensitivity, the ARSA system currently uses a complex arrangement of separate beta and gamma detectors to detect beta-gamma coincidences from characteristic radioxenon isotopes in small samples of xenon extracted from large volumes of air. The coincidence measurement is very sensitive, but the large number of detectors and photomultiplier tubes requires careful calibration. A simplified approach is to use a single phoswich detector, consisting of optically coupled plastic and CsI scintillators. In the phoswich detector, most beta particles are absorbed in the plastic scintillator and most gamma rays are absorbed in the CsI, and pulse shape analysis of the detector signal is used to detect coincidences. As only a single detector and electronics readout channel is used, the complexity of the system is greatly reduced. Previous studies with a planar detector have shown that the technique can clearly separate beta only, gamma only and coincidence events, does not degrade the energy resolution, and has an error rate for detecting coincidences of less than 0.1%. In this paper, we will present the design of a phoswich well detector, consisting of a 1'' diameter plastic cell enclosed in a 3'' CsI crystal. Several variations of the well detector geometry have been studied using Monte Carlo modeling and evaluated for detection efficiency, effects on energy resolution, and ease of manufacturing. One prototype detector has been built and we will present here some preliminary experimental results characterizing the detector in terms of energy resolution and its ability to separate beta only, gamma only, and coincidence events.

Download or read book Development of a COTS Radioxenon Detector System Using Phoswich Detectors and Pulse Shape Analysis written by and published by . This book was released on 2008 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: Several of the radioxenon detection systems developed for the International Monitoring System use beta/gamma coincidence detection to achieve high sensitivity. These systems use an arrangement of separate beta and gamma detectors to detect beta/gamma coincidence events characteristic of the different radioxenon isotopes. While very sensitive to small amounts of radioxenon, they also require careful calibration and gain matching of several detectors and photomultiplier tubes. An alternative approach is the use of a single phoswich detector in which beta-gamma coincidences are detected by pulse shape analysis (PSA). We previously reported on prototype phoswich well detectors, consisting of a fast plastic scintillator (absorbing betas) optically coupled to a slower CsI(Tl) scintillator (absorbing gammas). These detectors require only a single photomultiplier tube and an electronics readout channel. Beta/gamma coincidences create characteristic "fast/slow" signals that can easily be distinguished from "slow only" or "fast only" non-coincident interactions. We describe the development of a commercial off-the-shelf (COTS) radioxenon detector system based on such phoswich detectors. The PSA functions were implemented using the digital signal processor in a set of commercial readout electronics that is also compatible with ARSA and SAUNA detectors. These functions detect coincidences in real time and accumulate 2D histograms in on-board memory. The acquisition and the PSA functions can also be integrated into larger-scale acquisition and control software. Several phoswich detectors have been characterized for energy resolution, separation of coincidence events in 2D beta/gamma energy histograms, and detection efficiency. A test pulser module has been developed to support monitoring and testing of the electronics for state of health during operation. The phoswich detector, readout electronics, and software are now available as a COTS product package.

Download or read book Preliminary Experiments with a Triple Layer Phoswich Detector for Radioxenon Detection written by and published by . This book was released on 2008 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: The International Monitoring System (IMS) employs radiation detectors to monitor atmospheric or underground nuclear weapons tests. These detectors should be able to detect ultra low concentrations of xenon radioisotopes in the atmosphere. Exploiting the fact that the most interesting xenon radioisotopes emit a beta or conversion electron (CE) in coincidence with an X-ray or gamma-ray, these detectors have been designed and optimized to record coincidence events from the radioxenon isotopes. The IMS currently uses detection systems in which beta/CE and X-ray/gamma-ray are measured in separate detectors. Although the ARSA system is able to detect very low concentrations of radioxenon, its complexity makes the beta and gamma-ray energy calibration very difficult. Phoswich technology, accompanied by digital signal processing of photomultiplier tube (PMT) pulses, can simplify radioxenon detection. If well designed, like other current sensitive radioxenon detectors, a phoswich detector is also capable of detecting beta/gamma coincidence events using digital-pulse-shape analysis. We have designed a two-channel triple-layer phoswich detector for radioxenon detection. Each phoswich detector consists of three scintillation layers: a thin plastic (1.5mm) scintillator for detection of beta and CE, a CaF2 layer (2mm) for X-ray detection and a NaI layer (25.4mm) for gamma-ray measurement. A two-channel FPGA-based Digital Pulse Processor, DPP2.0, (250 MHz, 12 bits) has been designed and constructed for capturing and transferring valid phoswich pulses to the PC. A graphical user interface (GUI) also has been developed to control the DPP2.0, digitally analyze phoswich pulses, and reconstruct the 2-D beta/gamma coincidence spectra. In this paper, our digital pulse shape discrimination technique, the DPP2.0, and the GUI are introduced. At the end, our preliminary measurements with the prototypic phoswich detector are discussed.

Download or read book Real time Radioxenon Measurement Using a Compton suppressed Well type Phoswich Detector for Nuclear Explosion Monitoring written by Bemnet Alemayehu and published by . This book was released on 2013 with total page 115 pages. Available in PDF, EPUB and Kindle. Book excerpt: Radioxenon detection is a technique used to monitor nuclear explosion and verify the Comprehensive Nuclear-Test-Ban Treaty (CTBT). Because of an ultra-low concentration of radioxenon at radioxenon monitoring stations, radioxenon detection systems must have high sensitivity. This sensitivity is measured in terms of detector's minimum detectable concentration (MDC). It is required that radioxenon monitoring systems should have a MDC of less than or equal to 1 mBq/m3 for 133Xe. A Well-type Actively Shielded Phoswich Detector (WASPD) for radioxenon detection was designed and assembled at the Radiation Detection and Dosimetry lab at Oregon State University. The active shielding mechanism is integrated into the phoswich detector to improve the MDC of the radioxenon by reducing unwanted background events. Anode pulses were processed using a user programmable digital pulse processor. All digital processing functions were implemented in a FPGA device in real-time. The detector was characterized for different radioxenon isotopes. MDC calculation of the detector showed that the results are close or below 1 mBq/m3 for all radioxenon isotopes.

Download or read book Comparison of the Phoswich and ARSA type Detectors for Radioxenon Detection written by Rebecca Morgan Ward and published by . This book was released on 2010 with total page 164 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Comprehensive Nuclear Test Ban Treaty verification regime mandates atmospheric monitoring for the four radioxenon isotopes that are produced in high abundance in a nuclear explosion: [superscript 131m]Xe, [superscript 133m]Xe, [superscript 133g]Xe, and [superscript 135g]Xe. This mandate has driven the development of improved xenon detectors, including a phoswich detector, which has potential to replace the ARSA detector in the International Monitoring System. In this experiment, the four relevant radioxenon isotopes were produced through neutron activation and the phoswich detector was used to attain spectra from the gas. Spectral characteristics and resolution of the phoswich spectra were compared to an ARSA-type [beta]-[gamma] coincidence detector to perform an overall evaluation of the phoswich detector. The results indicated that spectral characteristics and resolutions for the phoswich were comparable to the ARSA-type detector, with slightly improved beta detection. As an additional test of the new detector's capabilities, a tailored spectrum designed to mimic a nuclear explosion signature was produced and analyzed with the detector.

Download or read book A Multi Layer Phoswich Radioxenon Detection System Reporting Period 07 written by and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: During this quarter, the detector manufacturer (Saint-Gobain) delivered one side of the prototype two-channel phoswich detector (XEPHWICH). Once received, our Digital Pulse Processor (DPP1, 12-bit/100 MHz) was employed to capture and digitally process phoswich pulses from laboratory radioactive sources. Our previous pulse shape discrimination algorithm was modified by utilizing three trapezoidal digital filters. This algorithm provides a two-dimensional plot in which the pulse shapes of interest are classified and then can be well identified. The preliminary experimental results will be presented at the 2007 Informal Xenon Monitoring Workshop. The DPP2 (two-channel, 12-bit/ 250 MHz Digital Pulse Processor) is at the prototyping stage. The analog sections have been designed, prototyped and tested. A 6-layer Printed Circuit Board (PCB) was designed, ordered and delivered. The board components were ordered and are now being assembled and examined for proper functionality. In addition, the related FPGA hardware description code (using VHDL) is under development and simulation. Additionally, our researchers have been studying materials regarding wavelet transforms for incorporation into the project. Wavelet transform is an interesting tool for signal processing; one use for our purpose would be to de-noise the detector signal and to express the signal in a few coefficients for signal compression and increased speed. Light capture efficiency modeling and analysis was performed on the XEPHWICH design. Increased understanding of the modeling software was obtained by the discovery of a bug and successful workaround techniques with the DETECT2000 software. Further modeling and plot generation experience was had by the continued use of CERN's ROOT and GEANT4 software packages. Simulations have been performed to compare the output of points versus planes in light capture efficiency. An additional simulation was made with a runtime that was an order-of-magnitude greater than previous simulations, to confirm convergence of the solutions provided by our software methods. We have initiated our investigation into the radon signature expected in our XEPHWICH system. We intend to utilize this signature to confirm earth movement, in the event of an underground nuclear explosion, by continuously monitoring radon levels and noting increases in radon concentration in conjunction with increased levels of radioxenons. The research group is also designing and constructing a fission chamber to be used for the collection of radioxenon gases following neutron bombardment of HEU in the Oregon State University TRIGA reactor. To this point, we have completed milling the aluminum housing and have modeled fission product nuclide production associated with the fissioning of HEU. Additionally, the students have been busy compiling the appropriate information in preparation for irradiation approvals. Using beta spectra of three initial nuclides collected on the prototype phoswich detector, spectral identification by a preliminary neural network was compared to that of solvers of a linear system of equations. Pre-processing in areas such as smoothing and endpoint identification is also being investigated as a means of improving spectral identification.

Download or read book Handbook of Radioactivity Analysis written by Michael F. L'Annunziata and published by Academic Press. This book was released on 2012-09-01 with total page 1419 pages. Available in PDF, EPUB and Kindle. Book excerpt: The updated and much expanded 3e of the Handbook of Radioactivity Analysis is an authoritative reference providing the principles, practical techniques, and procedures for the accurate measurement of radioactivity from the very low levels encountered in the environment to higher levels measured in radioisotope research, clinical laboratories, biological sciences, radionuclide standardization, nuclear medicine, nuclear power, and fuel cycle facilities and in the implementation of nuclear forensic analysis and nuclear safeguards. The book describes the basic principles of radiation detection and measurement and the preparation of samples from a wide variety of matrices, assists the investigator or technician in the selection and use of appropriate radiation detectors, and presents state-of-the-art methods of analysis. Fundamentals of radiation properties, radionuclide decay, the calculations involved, and methods of detection provide the basis for a thorough understanding of the analytical procedures. The Handbook of Radioactivity Analysis, 3e, is suitable as a teaching text for university and professional training courses. - The only comprehensive reference that describes the principles of detection and practical applications of every type of radioactivity detector currently used. The new 3e is broader in scope, with revised and expanded chapters, new authors, and seven new chapters on Alpha Spectrometry, Radionuclide Standardization, Radioactive Aerosol Measurements, Environmental Radioactivity Monitoring, Marine Radioactivity Analysis, Nuclear Forensic Analysis and Analytical Techniques in Nuclear Safeguards - Discusses in detail the principles, theory and practice applied to all types of radiation detection and measurement, making it useful for both teaching and research

Download or read book Prototyping a Triple layer Phoswich Detection System written by Christopher L. Duncan and published by . This book was released on 2011 with total page 103 pages. Available in PDF, EPUB and Kindle. Book excerpt: Multi-layer optically coupled scintillation based radiation detectors, known as phoswich detectors, have rapidly evolved in recent years. During the same time, digital signal processing has improved radiation discrimination accuracy and enhanced reliability, while reducing complexity and size of traditional analog signal processing methods. A new generation of high-speed radiation detectors that can measure mixed radiation fields has been developed by coupling these advancements. A prototype of one of the first commercially available phoswich detection systems has been analyzed to determine operational characteristics. The phoswich detector was analyzed using a variety of radioactive sources across a battery of tests compiled from the literature, Federal government regulations, and end-users specifications. It was found that the phoswich detection system operates equally well in beta particle, gamma-ray, and combined radiation fields. Testing at 5 centimeters demonstrated the phoswich detector's gamma-ray full-energy-peak intrinsic efficiency to range from 0.64 to 3.25 percent, full-energy-peak resolution from 6.29 (1332 keV) to 12.07 (356 keV) percent, and detectable energy range from 30 keV to 2754 keV. Similar testing for beta particles demonstrated an intrinsic efficiency of up to 58 percent. The system did exhibit saturation in radiation fields above 0.008 uCi when used with MATLAB. The phoswich detection system demonstrated that it is quite capable of accurately measuring the type and energy of radiation present in combined beta particle and gamma-ray radiation fields.

Download or read book Gas Turbine Combustion Fourth Edition written by Arthur H. Lefebvre and published by CRC Press. This book was released on 2011-06-22 with total page 520 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents a complete global examination of the complications, diagnoses, and management of HIV infections. This is essential for the HIV specialist and for those involved in HIV care, this book provides: information on the constantly changing and expanding drug therapies and treatment strategies for HIV the latest developments and frequently updated treatment guidelines includes new chapter on global efforts against HIV/AIDS. Draws from author's international experience includes a chapter on HIV and aging-hot topic in the field looks at the expansion and routinization of HIV testing a complete global examination of the complications, diagnoses, and management of HIV infections expert and authoriatative advice from Joseph R. Masci; Director of Medicine at Elmhurst Hospital Center in New York, who is highly respected in the field user friendly sections: core curriculum in HIV medicine, special populations, and systems of care up-to-date references, ensuring you have access to the most recent information

Download or read book Gamma Ray Imaging written by Junwei Du and published by Springer Nature. This book was released on 2023-09-12 with total page 248 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book will provide readers with a good overview of some of the most recent advances in the field of detector technology for gamma-ray imaging, especially as it pertains to new applications. There will be a good mixture of general chapters in both technology and applications in medical imaging and industrial testing. The book will have an in-depth review of the research topics from world-leading specialists in the field. The conversion of the gamma-ray signal into analog/digital value will be covered in some chapters. Some would also provide a review of CMOS chips for gamma-ray image sensors.

Download or read book Radionuclides in the Environment written by David A. Atwood and published by John Wiley & Sons. This book was released on 2013-02-19 with total page 546 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nuclear energy is the one energy source that could meet the world's growing energy needs and provide a smooth transition from fossil fuels to renewable energy in the coming decades and centuries. It is becoming abundantly clear that an increase in nuclear energy capacity will, and probably must, take place. However, nuclear energy and the use of radionuclides for civilian and military purposes lead to extremely long-lived waste that is costly and highly problematic to deal with. Therefore, it is critically important ot understand the environmental implications of radionuclides for ecosystems and human health if nuclear energy is to be used to avoid the impending global energy crisis. The present volume of the EIC Books series addresses this critical need by providing fundamental information on environmentally significant radionuclides. The content of this book was developed in collaboration with many of the authors of the chapters. Given the enormity of the subject the Editor and the Authors had to be judicious in selecting the chapters that would appropriately encompass and describe the primary topics, particularly those that are of importance to the health of ecosystems and humans. The resulting chapters were chosen to provide this information in a book of useful and appropriate length. Each chapter provides fundamental information on the chemistry of the radionuclides, their occurrence and movement in the enivornment, separation and analyses, and the technologies needed for their remediation and mitigation. The chapters are structured with a common, systematic format in order to facilitate comparions between elements and groups of elements. About EIC Books The Encyclopedia of Inorganic Chemistry (EIC) has proved to be one of the defining standards in inorganic chemistry, and most chemistry libraries around the world have access either to the first of second print editon, or to the online version. Many readers, however, prefer to have more concise thematic volumes, targeted to their specific area of interest. This feedback from EIC readers has encouraged the Editors to plan a series of EIC Books, focusing on topics of current interest. They will appear on a regular basis, and will feature leading scholars in their fields. Like the Encyclopedia, EIC Books aims to provide both the starting research student and the confirmed research worker with a critical distillation of the leading concepts in inorganic and bioinorganic chemistry, and provide a structured entry into the fields covered. This volume is also available as part of Encyclopedia of Inorganic Chemistry, 5 Volume Set. This set combines all volumes published as EIC Books from 2007 to 2010, representing areas of key developments in the field of inorganic chemistry published in the Encyclopedia of Inorganic Chemistry. Find out more.

Download or read book Measurement and Detection of Radiation written by Nicholas Tsoulfanidis and published by Hemisphere Pub. This book was released on 1983 with total page 602 pages. Available in PDF, EPUB and Kindle. Book excerpt: Assuming a basic knowledge of calculus, differential equations and some atomic physics, this classic bestseller enables students to select the proper detector, analyze the results of counting experiments, and perform radiation measurements following proper health physics procedures. Examples and problems in each chapter ensure that students understand the concepts presented. The book cover long-range alpha detector LRAD, pure geranium detectors, magnetic and electrostatic spectrometers, position-sensitive detectors, the LSL-M2 unfolding code, compensated ion chambers, self-powered neutron detectors, new protection guides, and exposure limits. A solutions manual is available for qualifying instructors.

Download or read book Handbook of Radioactivity Analysis written by Michael F. L'Annunziata and published by Academic Press. This book was released on 2020-03-07 with total page 1076 pages. Available in PDF, EPUB and Kindle. Book excerpt: Handbook of Radioactivity Analysis: Radiation Physics and Detectors, Volume One, and Radioanalytical Applications, Volume Two, Fourth Edition, constitute an authoritative reference on the principles, practical techniques and procedures for the accurate measurement of radioactivity - everything from the very low levels encountered in the environment, to higher levels measured in radioisotope research, clinical laboratories, biological sciences, radionuclide standardization, nuclear medicine, nuclear power, and fuel cycle facilities, and in the implementation of nuclear forensic analysis and nuclear safeguards. It includes sample preparation techniques for all types of matrices found in the environment, including soil, water, air, plant matter and animal tissue, and surface swipes.Users will find the latest advances in the applications of radioactivity analysis across various fields, including environmental monitoring, radiochemical standardization, high-resolution beta imaging, automated radiochemical separation, nuclear forensics, and more. - Spans two volumes, Radiation Physics and Detectors and Radioanalytical Applications - Includes a new chapter on the analysis of environmental radionuclides - Provides the latest advances in the applications of liquid and solid scintillation analysis, alpha- and gamma spectrometry, mass spectrometric analysis, Cherenkov counting, flow-cell radionuclide analysis, radionuclide standardization, aerosol analysis, high-resolution beta imaging techniques, analytical techniques in nuclear forensics, and nuclear safeguards - Describes the timesaving techniques of computer-controlled automatic separation and activity analysis of radionuclides - Provides an extensive table of the radiation characteristics of most radionuclides of interest for the radioanalytical chemist

Download or read book Nuclear Principles in Engineering written by Tatjana Jevremovic and published by Springer Science & Business Media. This book was released on 2009-04-21 with total page 558 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nuclear engineering plays an important role in various industrial, health care, and energy processes. Modern physics has generated its fundamental principles. A growing number of students and practicing engineers need updated material to access the technical language and content of nuclear principles. "Nuclear Principles in Engineering, Second Edition" is written for students, engineers, physicians and scientists who need up-to-date information in basic nuclear concepts and calculation methods using numerous examples and illustrative computer application areas. This new edition features a modern graphical interpretation of the phenomena described in the book fused with the results from research and new applications of nuclear engineering, including but not limited to nuclear engineering, power engineering, homeland security, health physics, radiation treatment and imaging, radiation shielding systems, aerospace and propulsion engineering, and power production propulsion.

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1991 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Monitoring a Comprehensive Test Ban Treaty written by Eystein S. Husebye and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 843 pages. Available in PDF, EPUB and Kindle. Book excerpt: An international treaty banning the testing of any nuclear device in any environment - a comprehensive test ban treaty (CTBT) - has been on the political agenda for nearly 40 years. Objections to a CTBT have been political, technical, or a combination of both. However, the possibilities seem better after the end of the Cold War. In the prevailing, cooperative disarmament climate a CTBT appears likely to be approved by most countries in 1996. Hence the great current interest in monitoring technologies and capabilities. Such issues are comprehensively addressed here, a preamble being devoted to the political developments and setbacks over the past 40 years. Since seismic means are considered the dominant monitoring element, they are explored in detail. Contributions cover network deployments, advanced signal processing, wave propagation in heterogeneous media, and seismic source representations, and a variety of techniques for source classification (including neural networks). Complementary monitoring techniques, such as hydroacoustics, radionuclides and infrasound, are also summarised. The IAEA operation for monitoring compliance with the Non-Proliferation Treaty is also presented. The book also includes eyewitness accounts of the Soviet 50 Mt megabomb development and test, as well as the efforts made by the state to monitor the nuclear test programmes of the western powers. Includes some 33 articles written by distinguished scientists active in CTBT monitoring research for decades.