Download or read book Development of a Cost effective Portable Neutron Imager and Spectrometer Using Sinusoid based Multiplexing of Silicon Photomultipliers and Plastic Scintillators written by Marc Alan Wonders and published by . This book was released on 2020 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Nuclear nonproliferation and nuclear security require tools to detect, characterize, and locate special nuclear material (SNM). The measurement of neutrons emitted from SNM offers a non-destructive means of doing so, and neutron imaging is a particularly attractive application of neutron measurements to better understand a neutron source for various applications. A field-deployable neutron imager could, for example, be used to locate an improvised nuclear device for emergency response, verify the presence of a nuclear warhead in a disarmament scenario, confirm nuclear material declarations for nuclear safeguards, or find a nuclear weapon in certain envisioned warfighting situations. Unfortunately, the established methods of neutron imaging are difficult to translate from a laboratory setting to the field, primarily due to large sizes and limited maneuverability. The neutron imaging method with the greatest potential for compactness and portability is the neutron scatter camera (NSC) because it requires no modulation of the incoming signal, no moving parts, and does not use gases in the system. Beneficially, NSCs in principle also offer full four-pi angular sensitivity and inherently measure the energy of incident neutrons on an event-by-event basis. Advances in light sensor technology, for example in the development of silicon photomultipliers (SiPMs), have enabled the conception of truly compact NSCs: the single volume NSC and the quasi-single volume NSC. The close spacing of and position sensitivity within detector elements in these designs also enables much greater imaging efficiency. The quasi-single volume NSC is likely more feasible to construct in the near-term, and, within this design space, multiple imager configurations are possible with different performance in different characteristics such as detection efficiency, angular resolution, and cost. Performance in these characteristics typically varies inversely with that of the others, and different applications might prefer different qualities, discouraging a one-size-fits-all approach. This dissertation develops a compact, portable quasi-single volume NSC with an emphasis on inexpensively achieving a high detection efficiency. To accomplish this objective, SiPMs and plastic scintillators are chosen to comprise the imager, and a channel multiplexing method is used to increase the number of detector elements that can be used given digitization hardware restrictions. Extensive assessment of SiPM technology is carried out, and a novel sinusoid-based multiplexing method designed for SiPMs is created and shown to be effective and to maintain good detector performance. Geant4 simulations are used to design the multiplexed neutron imager (MiNI) and understand the effects of multiplexing, leading to the selection of a 32-scintillator 16-digitizer channel configuration. A number of calibrations are carried out to enable the imaging and spectroscopy capability of the MiNI, and where appropriate, these are also used as a large-scale test of the multiplexing method. The MiNI is tested with a 252Cf spontaneous fission source and its imaging capability is demonstrated with the source at multiple locations around the MiNI, as well as its spectroscopic capability. The MiNI developed in this dissertation is the first multiplexed NSC and the first reported quasi-single volume NSC composed of more than eight elements or plastic scintillators to fully demonstrate effective neutron imaging. Ultimately, the MiNI establishes the feasibility of multiplexing a compact NSC and demonstrates a route to achieve high imaging efficiency in a cost-effective manner.
Download or read book The Development of a Fast Neutron Spectrometer Using Silicon Surface Barrier Diodes written by J. J. Baum and published by . This book was released on 1961 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Development of A Self Biased High Efficiency Solid State Neutron Detector for MPACT Applications written by and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Neutron detection is an important aspect of materials protection, accounting, and control for transmutation (MPACT). Currently He-3 filled thermal neutron detectors are utilized in many applications; these detectors require high-voltage bias for operation, which complicates the system when multiple detectors are used. In addition, due to recent increase in homeland security activity and the nuclear renaissance, there is a shortage of He-3, and these detectors become more expensive. Instead, cheap solid-state detectors that can be mass produced like any other computer chips will be developed. The new detector does not require a bias for operation, has low gamma sensitivity, and a fast response. The detection system is based on a honeycomb-like silicon device, which is filled with B-10 as the neutron converter; while a silicon p-n diode (i.e., solar cell type device) formed on the thin silicon wall of the honeycomb structure detects the energetic charged particles emitted from the B-10 conversion layer. Such a detector has ~40% calculated thermal neutron detection efficiency with an overall detector thickness of about 200?m. Stacking of these devices allows over 90% thermal neutron detection efficiency. The goal of the proposed research is to develop a high-efficiency, low-noise, self-powered solid-state neutron detector system based on the promising results of the existing research program. A prototype of this solid-state neutron detector system with sufficient detector size (up to 8-inch diam., but still portable and inexpensive) and integrated with interface electronics (e.g., preamplifier) will be designed, fabricated, and tested as a coincidence counter for MPACT applications. All fabrications proposed are based on silicon-compatible processing; thus, an extremely cheap detector system could be massively produced like any other silicon chips. Such detectors will revolutionize current neutron detection systems by providing a solid-state alternative to traditional gas-based neutron detectors.
Download or read book Development of a Compact Neutron Generator to be Used For Associated Particle Imaging Utilizing a RF Driven Ion Source written by Ying Wu and published by . This book was released on 2009 with total page 250 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ion source development plays an important role for improving and advancing the neutron generator technology used for active interrogation techniques employed by the Department of Homeland Security. Active neutron interrogation using compact neutron generators has been around since the late 1950's for use in oil well logging. However, since the September 11th, 2001 terrorists attack, much attention has been paid to the field of active neutron interrogation for detecting hidden explosives and special nuclear materials (SNM) in cargo and luggage containers through the development of effective and efficient radioactive sources and detectors. In particular, the Associated Particle Imaging (API) method for detecting and imaging explosives is of great interest New compact neutron generators will help to enhance the capabilities of existing threat detection systems and promote the development of cutting-edge detection technologies. The work performed in this thesis includes the testing of various ion source configurations and the development and characterization of an inductively coupled radio frequency (RF) ion source for use in compact neutron generators. These ion source designs have been investigated for the purpose of D-T neutron generation for explosive detection via the Associated Particle Imaging (API) technique. API makes use of the 3.5 MeV alpha particles that are produced simultaneously with the 14 MeV neutrons in the deuterium-tritium (2D(3T, n)4) fusion reaction to determine the direction of the neutrons and to reduce background noise. The Associated Particle Imaging neutron generator required a beam spot of 1-mm or less in diameter at the target in order to achieve the necessary spatial image resolution. For portable neutron generators used in API, the ion source and target cannot be water-cooled and the power deposited on the target must be low. By increasing the atomic ion fraction, the ion beam can be used more efficiently to generate neutrons, resulting in a lower beam power requirement and an increased lifetime of the alpha detector inside the acceleration column. Various source configurations, antenna design, and permanent magnet placement have been investigated so as to develop an ion source which could provide high monatomic deuterium species and high current density at relatively low RF powers (less than 200 W). In this work, an RF ion source was developed that uses an external, planar, spiral antenna at 13.56 MHz with a quartz source body and side multi-cusp magnets to generate hydrogen isotope plasmas with high mono-atomic ion species (> 80%) while consuming only 150 watts of power and operating under 10 mTorr of gas pressure. A single acceleration gap with a secondary electron suppression electrode are used in the tube. Experimental measurements of the ion source plasma parameters including ion current density, atomic ion fraction, ignition and operating pressures, electron temperature, and electron density are presented along with a discussion on the ion optics and engineering challenges. It is shown that the measured neutron yield for the developed D-D neutron generator was 2 x 105 n/s, which scales to 8 x 107 n/s for D-T operation. In addition, initial measurements of the neutron generator performance including the beam spot size, associated particle detection, and neutron tube (without pumping) operation will be discussed. Some suggestions for future improvement are also presented in this dissertation.
Download or read book NMIS with Imaging and Gamma Ray Spectrometry for Pu HEU HE and Other Materials written by and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The Nuclear Material Identification System (NMIS) has been under development at ORNL and the National Nuclear Security Administration (NNSA) Y-12 National Security Complex since 1984. In the mid-1990s, what is now the US Department of Energy (DOE) Office of Nuclear Verification (ONV) realized that it was a useful technology for future arms control treaty applications and supported further development of the system. In 2004, fast-neutron imaging was incorporated into the system. In 2007, the ONV decided to develop a fieldable version of the system, designated as FNMIS, for potential use in future treaties. The FNMIS is being developed to be compatible with the eventual incorporation of gamma-ray spectrometry and an information barrier. This report addresses how and what attributes could be determined by the FNMIS system with gamma-ray spectrometry. The NMIS is a time-dependent coincidence system that incorporates tomographic imaging (including mapping of the fission sites) and gamma-ray spectrometry. It utilizes a small, lightweight (30 lb), portable deuterium-tritium (DT) neutron (14.1 MeV) generator (4 x 107 neutrons/second) for active interrogation and can also perform passive interrogation. A high-purity germanium (HPGe) gamma-ray detector with multichannel analysis can be utilized in conjunction with the source for active interrogation or passively. The system uses proton recoil scintillators: 32 small 2.5 x 2.5 x 10.2-cm-thick plastic scintillators for imaging and at least two 2 x 2 arrays of 27 x 27 x 10-cm-thick plastic scintillators that detect induced fission radiation. The DT generator contains an alpha detector that time and directionally tags a fan beam of some of the neutrons emitted and subdivides it into pixels. A fast (1 GHz) time correlation processor measures the time-dependent coincidence among all detectors in the system. A computer-controlled scanner moves the small detectors and the source appropriately for scanning a target object for imaging. The system is based on detection of transmitted 14.1 MeV neutrons, fission neutrons, and gamma rays from spontaneous, inherent source fission of the target, fission neutrons and gamma rays induced by the external DT source, gamma rays from natural emissions of uranium and plutonium, and induced gamma-ray emission by the interaction of the 14.1 MeV neutrons from the DT source. The NMIS can and has been used with a time-tagged californium spontaneous fission source. It has also been used with pulsed interrogation sources such as LINACs, DT, and deuterium-deuterium (DD) sources. This system is uniquely suited for detection of shielded highly enriched uranium (HEU), plutonium, and other special nuclear materials and detection of high explosives (HE) and chemical agents. The NMIS will be adapted to utilize a trusted processor that incorporates information barrier and authentication techniques using open software and then be useful in some international applications for materials whose characteristics may be classified. The proposed information barrier version of the NMIS system would consist of detectors and cables, the red (classified side) computer system, which processes the data, and the black (unclassified side) computer, which handles the computer interface. The system could use the 'IB wrapper' concept proposed by Los Alamos National Laboratory and the software integrity (digital signatures) system proposed by Sandia. Since it is based entirely on commercially available components, the entire system, including NMIS data acquisition boards, can be built with commercial off-the-shelf components. This system is being developed into a fieldable system (FNMIS) for potential arms control treaties by the ONV. The system will be modularly constructed with the RF shielded modules connected to the processor by appropriate control and signal cable in metal conduit. The FNMIS is presently being designed for eventual incorporation of gamma-ray spectrometry and an informati ...
Download or read book Modern essays written by and published by . This book was released on 1936 with total page 97 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Development and Testing of an Organic Scintillator Detector for Fast Neutron Spectrometry written by George Spencer Mickum and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The use of organic scintillators is an established method for the measurement of neutron spectra above several hundred keV. Fast neutrons are detected largely by proton recoils in the scintillator resulting from neutron elastic scattering with hydrogen. This leads to a smeared rectangular pulse-height distribution for monoenergetic neutrons. The recoil proton distribution ranges in energy from zero to the incident neutron energy. In addition, the pulse-height distribution is further complicated by structure due to energy deposition from alpha particle recoils from interactions with carbon as well as carbon recoils themselves. In order to reconstruct the incident neutron spectrum, the pulse-height spectrum has to be deconvoluted (unfolded) using the computed or measured response of the scintillator to monoenergetic neutrons. In addition gamma rays, which are always present when neutrons are present, lead to Compton electron recoils in the scintillator. Fortunately, for certain organic scintillators, the electron recoil events can be separated from the heavier particle recoil events in turn to distinguish gamma-ray induced events from neutron-induced events. This is accomplished by using the risetime of the pulse from the organic scintillator seen in the photomultiplier tube as a decay of light. In this work, an organic scintillator detection system was assembled which includes neutron-gamma separation capabilities to store the neutron-induced and gamma-induced recoil spectra separately. An unfolding code was implemented to deconvolute the spectra into neutron and gamma energy spectra. In order to verify the performance of the system, a measurement of two reference neutron fields will be performed with the system, unmoderated Cf-252 and heavy-water moderated Cf-252. After the detection system has been verified, measurements will be made with an AmBe neutron source.
Download or read book Modern Aspects of Small Angle Scattering written by H. Brumberger and published by Springer Science & Business Media. This book was released on 2013-11-11 with total page 470 pages. Available in PDF, EPUB and Kindle. Book excerpt: Proceedings of the NATO Advanced Study Institute, Como, Italy, May 12--22, 1993
Download or read book Process Analytical Chemistry written by F. McLennan and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 391 pages. Available in PDF, EPUB and Kindle. Book excerpt: Process analytical chemistry (PAC) can be defined as the technology of obtaining quantitative and qualitative information about a chemical process in order to control or optimise its performance. This highly practical book provides an up-to-date introduction to the field with a special emphasis placed on industrial processes. Edited by representatives from one of the world's leading chemical companies and centres of excellence for research into the subject, the book is written by a transatlantic team of authors who provide a global perspective.
Download or read book Clark s Essential Physics in Imaging for Radiographers written by Ken Holmes and published by CRC Press. This book was released on 2013-10-10 with total page 202 pages. Available in PDF, EPUB and Kindle. Book excerpt: It is essential that any practitioner working in an imaging department and using ionizing radiation has a sound knowledge base. In order to understand the various factors affecting the production of diagnostic images, practitioners must demonstrate a grasp of the fundamental definitions of physics and how these principles may be applied to radiogra
Download or read book Electronic Imaging in Astronomy written by Ian S. McLean and published by Springer Science & Business Media. This book was released on 2008-08-17 with total page 576 pages. Available in PDF, EPUB and Kindle. Book excerpt: The second edition of Electronic Imaging in Astronomy: Detectors and Instrumentation describes the remarkable developments that have taken place in astronomical detectors and instrumentation in recent years – from the invention of the charge-coupled device (CCD) in 1970 to the current era of very large telescopes, such as the Keck 10-meter telescopes in Hawaii with their laser guide-star adaptive optics which rival the image quality of the Hubble Space Telescope. Authored by one of the world’s foremost experts on the design and development of electronic imaging systems for astronomy, this book has been written on several levels to appeal to a broad readership. Mathematical expositions are designed to encourage a wider audience, especially among the growing community of amateur astronomers with small telescopes with CCD cameras. The book can be used at the college level for an introductory course on modern astronomical detectors and instruments, and as a supplement for a practical or laboratory class.
Download or read book Small Animal SPECT Imaging written by Matthew A. Kupinski and published by Springer Science & Business Media. This book was released on 2007-05-27 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt: Small-Animal SPECT Imaging is an edited work derived from the first workshop on Small-Animal SPECT Imaging held January 14-16, 2004 at the University of Arizona, Tucson, AZ, USA. The overall goal of the meeting and therefore this volume is to promote information exchange and collaboration between the research groups developing systems for small-animal applications. Topics include the biomedical significance of small-animal imaging, an overview of detector technologies including scintillation cameras and semi-conductor arrays, imager design and data acquisition systems, animal handling and anesthesia issues, objective assessment of image quality, and system modeling and reconstruction algorithms.
Download or read book The Large Hadron Collider written by Lyndon R. Evans and published by EPFL Press. This book was released on 2009-01-01 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt: Describes the technology and engineering of the Large Hadron collider (LHC), one of the greatest scientific marvels of this young 21st century. This book traces the feat of its construction, written by the head scientists involved, placed into the context of the scientific goals and principles.
Download or read book Electronic Portable Instruments written by Halit Eren and published by CRC Press. This book was released on 2003-10-16 with total page 424 pages. Available in PDF, EPUB and Kindle. Book excerpt: With the availability of advanced technologies, digital systems, and communications, portable instruments are rapidly evolving from simple, stand alone, low-accuracy measuring instruments to complex multifunctional, network integrated, high-performance digital devices with advanced interface capabilities. The relatively brief treatments these instr
Download or read book Advances in Systems Control and Automation written by Avinash Konkani and published by Springer. This book was released on 2017-12-11 with total page 727 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book comprises the select proceedings of the ETAEERE 2016 conference. The book aims to shed light on different systems or machines along with their complex operation, behaviors, and linear–nonlinear relationship in different environments. It covers problems of multivariable control systems and provides the necessary background for performing research in the field of control and automation. Aimed at helping readers understand the classical and modern design of different intelligent automated systems, the book presents coverage on the control of linear and nonlinear systems, intelligent systems, stochastic control, knowledge-based systems applications, fault diagnosis and tolerant control, real-time control applications, etc. The contents of this volume will prove useful to researchers and professionals alike.
Download or read book The Large Hadron Collider written by Lyndon Evans and published by . This book was released on 2018 with total page 305 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Solid State Characterization of Pharmaceuticals written by Richard A. Storey and published by John Wiley & Sons. This book was released on 2011-03-31 with total page 557 pages. Available in PDF, EPUB and Kindle. Book excerpt: The field of solid state characterization is central to the pharmaceutical industry, as drug products are, in an overwhelming number of cases, produced as solid materials. Selection of the optimum solid form is a critical aspect of the development of pharmaceutical compounds, due to their ability to exist in more than one form or crystal structure (polymorphism). These polymorphs exhibit different physical properties which can affect their biopharmaceutical properties. This book provides an up-to-date review of the current techniques used to characterize pharmaceutical solids. Ensuring balanced, practical coverage with industrial relevance, it covers a range of key applications in the field. The following topics are included: Physical properties and processes Thermodynamics Intellectual guidance X-ray diffraction Spectroscopy Microscopy Particle sizing Mechanical properties Vapour sorption Thermal analysis & Calorimetry Polymorph prediction Form selection
