Download or read book UTILIZATION OF PHOSWICH DETECTORS FOR SIMULTANEOUS MULTIPLE RADIATION DETECTION written by and published by . This book was released on 2003 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: A phoswich radiation detector is comprised of a phosphor sandwich in which several different phosphors are viewed by a common photomultiplier. By selecting the appropriate phosphors, this system can be used to simultaneously measure multiple radiation types (alpha, beta, gamma and/or neutron) with a single detector. Differentiation between the signals from the different phosphors is accomplished using digital pulse shape discrimination techniques. This method has been shown to result in accurate discrimination with highly reliable and versatile digital systems. This system also requires minimal component count (i.e. only the detector and a computer for signal processing). A variety of detectors of this type have been built and tested including: (1) a triple phoswich system for alpha/beta/gamma swipe counting, (2) two well-type detectors for measuring low levels of low energy photons in the presence of a high energy background, (3) a large area detector for measuring beta contamination in the presence of a photon background, (4) another large area detector for measuring low energy photons from radioactive elements such as uranium in the presence of a photon background. An annular geometry, triple phoswich system optimized for measuring alpha/beta/gamma radiation in liquid waste processing streams is currently being designed.
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 Digital Pulse Shape Discrimination Methods for Triple layer Phoswich Detectors Using Wavelets and Fuzzy Logic written by Siavash Yousefi and published by . This book was released on 2009 with total page 232 pages. Available in PDF, EPUB and Kindle. Book excerpt: A two-channel data acquisition system for simultaneous detection and discrimination of beta particles and gamma rays has been developed. Each channel measures and analyzes the input pulses resulting from the absorption of radiation in the layers of the detector. The detector is a triple-layer phoswich (phosphor sandwich) scintillation detector followed by a photomultiplier tube (PMT). The PMT amplifies the photons and converts them into an electric signal. The signal is digitized and sent to the host computer for further processing. Two new digital algorithms based on Fuzzy Logic and on the Continuous Wavelet Transform have been developed and are discussed in this thesis. In the first method, a de-noising algorithm based on the Wavelet Transform is implemented to reduce the effect of noise introduced by the analog channel and by the photomultiplier tube. Three new timing features are extracted and given as input to a fuzzy interface system. The main goal of fuzziness in a data set is to reduce the system complexity and to provide a model that allows for approximate results. Compared to the method which was originally implemented for this detector, the fuzzy algorithm shows a better performance in separating beta and gamma spectra, especially at high energies. Also, absorption in multiple layers is detected more efficiently. The second algorithm is based on the Continuous Wavelet Transform. The novelty of this method consists in using scale-domain features. Since the output pulse shape of the photomultiplier tube is a non-stationary signal, conventional Fourier methods are not efficient for analyzing these signals and most of the existing pulse shape discrimination methods use time-domain features. Therefore, a time-frequency space is better suited to analyze these non-stationary signals. This method shows better performance over existing time-domain methods in terms of robustness to noise and reliability. The simultaneous detection of beta particles and gamma rays has several applications (for instance detection of underground nuclear explosions). The methods presented in this thesis could also be used in alpha/beta/neutron/gamma discrimination systems for cancer diagnosis and treatment.
Download or read book Study of the Use of a Phoswich Detector for Aerial Radiometric Surveys written by E. J. Schneid and published by . This book was released on 1981 with total page 202 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book An Investigation of the Light Capture Properties of the XEPHWICH a Phoswich Radiation Detection System written by Sean E. Jones and published by . This book was released on 2009 with total page 128 pages. Available in PDF, EPUB and Kindle. Book excerpt: The XEPHWICH system is a phoswich type (multiple scintillator) radiation detector designed to detect several radioxenon isotopes with the goal of identifying covert nuclear explosions. The XEPHWICH system is designed with the sole purpose of replacing the Automated Radio-xenon Sampler/Analyzer (ARSA) in the United Nation's (UN) Comprehensive Test Ban Treaty's (CTBT) International Monitoring System (IMS). This study consists of two stages, computer simulation and laboratory experiment. The use of DETECT2000, a Monte-Carlo optical simulator, was the method by which optical performance and potential improvements to the XEPHWICH design were investigated. The laboratory experiment conducted in this study validated the modeling methods used in the study and investigated the effects of light capture efficiency on XEPHWICH system output. The experiment consisted of exposing the NaI(Tl) layer of the XEPHWICH to a lead collimated Cs-137 beam at varying locations, and comparing the differential energy spectra observed. The simulation work resulted in design considerations for improving the optical performance of the XEPHWICH. Additionally, through simulation, the optical performance of the XEPHWICH was characterized and can be compared to competing scintillator designs. The experimental observations included expected and unexpected effects that light capture properties had on the system signal. Of particular importance, the experimental results supported the modeling method applied, and demonstrated that an increase in expected light capture efficiency was associated with better energy resolution for a full energy peak in a differential pulse height spectrum.
Download or read book Development of an Alpha Beta Gamma Phoswich Based Radiation Detector for Nuclear Waste Stream Cleanup Processes written by and published by . This book was released on 2004 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: The goal of this research is to design, build and test a phoswich-based radiation detector for simultaneously monitoring all radioactive components in the effluent resulting from the cleanup of nuclear waste.
Download or read book Ionizing Radiation Detectors for Medical Imaging written by Alberto Del Guerra and published by World Scientific. This book was released on 2004 with total page 532 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ionizing Radiation Detectors for Medical Imaging contains tentechnical chapters, half of which are devoted to radiology and theother half to nuclear medicine. The last chapter describes thedetectors for radiotherapy and portal imaging. Each chapter addressescompletely a specific application. The emphasis is always on detectorfundamentals and detector properties. Where necessary, software andspecific applications are described in depth. This book is intended for graduate and undergraduate students inphysics and engineering who want to study medical imaging. Inaddition, scientists who are working in a specific sub-field ofmedical imaging can acquire from the book an up-to-date description ofthe state of the art in related sub-fields, within the scope ofionizing radiation detectors. Other scientists, as well as physicians, can use the book as a reference for medical imaging
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 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 Radiation Detection written by Douglas McGregor and published by CRC Press. This book was released on 2020-08-19 with total page 1851 pages. Available in PDF, EPUB and Kindle. Book excerpt: Radiation Detection: Concepts, Methods, and Devices provides a modern overview of radiation detection devices and radiation measurement methods. The book topics have been selected on the basis of the authors’ many years of experience designing radiation detectors and teaching radiation detection and measurement in a classroom environment. This book is designed to give the reader more than a glimpse at radiation detection devices and a few packaged equations. Rather it seeks to provide an understanding that allows the reader to choose the appropriate detection technology for a particular application, to design detectors, and to competently perform radiation measurements. The authors describe assumptions used to derive frequently encountered equations used in radiation detection and measurement, thereby providing insight when and when not to apply the many approaches used in different aspects of radiation detection. Detailed in many of the chapters are specific aspects of radiation detectors, including comprehensive reviews of the historical development and current state of each topic. Such a review necessarily entails citations to many of the important discoveries, providing a resource to find quickly additional and more detailed information. This book generally has five main themes: Physics and Electrostatics needed to Design Radiation Detectors Properties and Design of Common Radiation Detectors Description and Modeling of the Different Types of Radiation Detectors Radiation Measurements and Subsequent Analysis Introductory Electronics Used for Radiation Detectors Topics covered include atomic and nuclear physics, radiation interactions, sources of radiation, and background radiation. Detector operation is addressed with chapters on radiation counting statistics, radiation source and detector effects, electrostatics for signal generation, solid-state and semiconductor physics, background radiations, and radiation counting and spectroscopy. Detectors for gamma-rays, charged-particles, and neutrons are detailed in chapters on gas-filled, scintillator, semiconductor, thermoluminescence and optically stimulated luminescence, photographic film, and a variety of other detection devices.
Download or read book Introduction to Nuclear Radiation Detectors written by P. Ouseph and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 201 pages. Available in PDF, EPUB and Kindle. Book excerpt: There have been many interesting developments in the field of nuclear radiation detectors, especially in those using semiconduct ing materials. The purpose of this book is to present a survey of the developments in semiconductor detectors along with discus sions about gas counters and scintillation counters. These discus sions are directed to detector users, usually scientists and technicians in different fields such as chemistry, geology, bio chemistry, and medicine. The operation of these detectors is discussed in terms of basic properties, such as efficiency, energy resolution, and resolving time, which are defmed in the first chapter. Differences among these detectors in terms of these properties are pointed out. Chapter 2, on interaction of radiations with matter, discusses how different radiations lose energies in matter and how differences in their behavior in matter affect the design and operation of detectors. Although emphasis is placed on fundamentals throughout the book, the reader is also made aware of the new developments in the field of radiation quite often detection. The author has taught a course in radioisotopes for several years for science, engineering, medical, and dental students. The emphasis on topics varied from time to time to satisfy the varying interests of the students. However, the contents of this book formed the core of the course. About ten selected experiments on detectors were done along with this course (a list of these vii Preface viii experiments may be supplied on request).
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 Measurement and Detection of Radiation written by Nicholas Tsoulfanidis and published by CRC Press. This book was released on 2021-09-15 with total page 642 pages. Available in PDF, EPUB and Kindle. Book excerpt: As useful to students and nuclear professionals as its popular predecessors, this fifth edition provides the most up-to-date and accessible introduction to radiation detector materials, systems, and applications. There have been many advances in the field of radiation detection, most notably in practical applications. Incorporating these important developments, Measurement and Detection of Radiation, Fifth Edition provides the most up-to-date and accessible introduction to radiation detector materials, systems, and applications. It also includes more problems and updated references and bibliographies, and step-by-step derivations and numerous examples illustrate key concepts. New to the Fifth Edition: • Expanded chapters on semiconductor detectors, data analysis methods, health physics fundamentals, and nuclear forensics. • Updated references and bibliographies. • New and expanded problems.
Download or read book Radiation Detectors written by Cyril F. G. Delaney and published by . This book was released on 1992 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: From the pocket dosemeter and photographic emulsions to the superheated drop detector and the single particle calorimeter, this text describes the wide range of sensing apparatus used for observing and measuring nuclear radiation. Emphasis is placed on simple but thorough explanations of the underlying physics for each detector and on their applications. Introductions to the types of radiation and their interaction with matter lead to descriptions of well established devices such as ionization chambers, proportional and Geiger counters, scintillation counters, semiconductor detectors, and other more recent innovations such as semiconductor drift chambers and dark matter detectors. A separate chapter discusses sources of noise and their influence on the energy resolution achievable with different systems. The book has been written by two physicists who have worked and taught in the field for many years. It is intended for advanced undergraduates and graduate students as well as technicians and workers who use sources of ionizing radiation.
Download or read book Radiation Detection Systems written by Taylor & Francis Group and published by Devices, Circuits, and Systems. This book was released on 2021-11-05 with total page 704 pages. Available in PDF, EPUB and Kindle. Book excerpt: The advances in semiconductor detectors, scintillators, photodetectors such as SiPM, and readout electronics in the past decades have led to significant progress in terms of performance and greater choice of the detection tools in many applications. This second edition of Radiation Detection Systems presents the state-of-the-art in the design of detectors and integrated circuit design, in the context of medical imaging using ionizing radiation. The material in the book has been divided into two volumes. The first volume on Sensor Materials, Systems, Technology and Characterization Measurements puts more emphasis on sensor materials, detector and front electronics technology and designs as well as system optimization for different applications. It also includes characterization measurements of the developed detection systems. The second volume on Medical Imaging, Industrial Testing and Security Applications is devoted to more specific applications of detection systems in medical imaging, industrial testing and security applications. However, there is an unavoidable certain overlap in topics between both volumes. With its combined coverage of new materials and innovative new system approaches, as well as a succinct overview of recent developments, this two volumes set is an invaluable tool for any engineer, professional, or student working in electronics or an associated field.
Download or read book Handbook of Radioactivity Analysis written by Michael F. L'Annunziata and published by Academic Press. This book was released on 2012-08-16 with total page 1420 pages. Available in PDF, EPUB and Kindle. Book excerpt: Authoritative reference providing the principles, practical techniques, and procedures for the accurate measurement of radioactivity.
Download or read book A Two Channel Phoswich Detector for Dual and Triple Coincidence Measurements of Radioxenon Isotopes written by and published by . This book was released on 2007 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: As part of the Comprehensive Nuclear Test Ban Treaty, the International Monitoring System (IMS) has been established for monitoring xenon radioisotopes in the atmosphere to detect atmospheric or underground nuclear explosions. Experimental results from the Automated Radioxenon Sampler/Analyzer (ARSA) system, developed at Pacific Northwest National Laboratory, show that the system is capable of detecting very low concentrations of the fission product radioxenon isotopes (133)Xe, (133m)Xe, (131m)Xe and (135)Xe. To build a more practical radioxenon detection system as sensitive as the ARSA system but with reduced cost, size, power consumption and complexity, several detection systems have been developed or are currently under development. It has been shown (McIntyre et al. 2004) that triple coincidence measurements of beta, conversion electons (CE) and x-ray from the radioxenon gas provides a significant reduction of Compton scatter interference in the 30-keV line and therefore much lower (2-3 orders of magnitude) concentrations of (133)Xe can be detected even with a high radon background. The triple coincidence measurement eliminates the need for additional separation columns and traps (required for removing the background radon) and allows for reduced passive shielding as well, thus reducing the size and power consumption of the system. In this paper, a two-channel phoswich detector is introduced and studied. The detector consists of a thin hollow disk (with 2 mm thickness and 76.2 mm diameter) as the xenon gas cell, surrounded by two identical planar triple-layer phoswich detectors. This design provides a solid angle of about 3.4 pi for the gas cell, close to that of the ARSA system (tilde 3.5 pi). The planar shape of the detectors has several important advantages, among which are the reduced cost due to its simplicity, and because it has a minimum non-uniformity in light collection efficiency, will not unreasonably degrade the beta or gamma energy resolution.
