Download or read book Neutron Detectors for Fusion Reaction rate Measurements written by and published by . This book was released on 1994 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fusion reactions in an inertial-confinement fusion (ICF) target filled with deuterium or a deuterium/tritium fuel release nearly monoenergetic neutrons. Because most the neutrons leave the compressed target without collision, they preserve reaction-rate information as they travel radially outward from their point of origin. Three fast, neutron detector techniques, each capable of measuring the fusion reaction-rate of ICF targets, have been demonstrated. The most advanced detector is based on the fast rise-time of a commercial plastic scintillator material (BC-422) which acts as a neutron-to-light converter. Signals, which are recorded with a fast optical streak camera, have a resolution of 25 ps. Good signals can be recorded for targets producing only 5 x 107 DT neutrons. Two other detectors use knock-on collisions between neutrons and protons in a thin polyethylene (CH2) converter. In one, the converter is placed in front of the photocathode of an x-ray streak camera. Recoil protons pass through the photocathode and knock out electrons which are accelerated and deflected to produce a signal. Resolutions

Download or read book Neutron Detector for Fusion Reaction rate Measurements written by and published by . This book was released on 1993 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: We have developed a fast, sensitive neutron detector for recording the fusion reaction-rate history of inertial-confinement fusion (ICF) experiments. The detector is based on the fast rise-time of a commercial plastic scintillator (BC-422) and has a response

Download or read book 25 ps Neutron Detector for Measuring ICF target Burn History written by and published by . This book was released on 1994 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt: We have developed a fast, sensitive neutron detector for recording the fusion reaction-rate history of inertial-confinement fusion (ICF) experiments. The detector is based on the fast rise-time of a commercial plastic scintillator (BC-422) and has a response

Download or read book Measurement of Neutron Flux and Spectra for Physical and Biological Applications written by National Committee on Radiation Protection and Measurements (U.S.) and published by . This book was released on 1960 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Measurement of Neutron Flux and Spectra for Physical and Biological Applications written by National Committee on Radiation Protection and Measurements (U.S.) and published by . This book was released on 1960 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Results of an Attempt to Measure Increased Rates of the Reaction D 2 D 2 Yields He 3 N in a Nonelectrochemical Cold Fusion Experiment written by and published by . This book was released on 1989 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Spectrally matched Neutron Detectors Designed Using Computational Adjoint S sub N for Plug in Replacement of Helium 3 written by Scottie Walker and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Neutron radiation detectors are an integral part of the Department of Homeland Security (DHS) efforts to detect the illicit trafficking of radioactive or special nuclear materials into the U.S. In the past decade, the DHS has deployed a vast network of radiation detection systems at various key positions to prevent or to minimize the risk associated with the malevolent use of these materials. The greatest portion of this detection burden has been borne by systems equipped with 3He because of its highly desirable physical and nuclear properties. However, a dramatic increase in demand and dwindling supply, combined with a lack of oversight for the existing 3He stockpile has produced a critical shortage of this gas which has virtually eliminated its viability for detector applications. A number of research efforts have been undertaken to develop suitable 3He replacements; however, these studies have been solely targeted toward simple detection cases where the overall detection efficiency is the only concern. For these cases, an insertion of additional detectors or materials can produce reaction rates that are sufficient, because the neutron spectral response is essentially irrelevant. However, in applications such as safeguards, non-proliferation efforts, and material control and accountability programs (MC & A), a failure to use detectors that are spectrally matched to 3He can potentially produce dire consequences. This is because these more difficult detection scenarios are associated with fissile material assessments for 239Pu and other actinides and these analyses have almost universally been calibrated to an equivalent 3He response. In these instances, a "simple" detector or material addition approach is neither appropriate nor possible, due to influences resulting from the complex nature of neutron scattering in moderators, cross sections, gas pressure variations, geometries, and surrounding structural interference. These more challenging detection cases require a detailed computational transport analysis be performed for each specific application. A leveraged approach using adjoint transport computations that are validated by forward transport and Monte Carlo computations and laboratory measurements can address these more complex detection cases and this methodology was utilized in the execution of the research. The initial task was to establish the fidelity of a computational approach by executing radiation transport models for existing BF3 and 3He tubes and then comparing the modeling results to laboratory measurements made using these identical devices. Both tubes were 19.6 cm in height, 1-inch in diameter, and operated at 1 and 4 atm pressure respectively. The models were processed using a combination of forward Monte Carlo and forward and adjoint 3-D discrete ordinates (SN) transport methods. The computer codes MCNP5 and PENTRAN were used for all calculations of a nickel-shielded plutonium-beryllium (PuBe) source term that provided a neutron output spectra equivalent to that of weapons-grade plutonium (WGPu). Once the computational design approach was validated, the adjoint SN method was used to iteratively identify six distinct plug-in models that matched the neutron spectral response and reaction rate of a 1-inch diameter 3He tube with a length of 10 cm and operating at 4 atm pressure. The equivalent designs consist of large singular tubes and dual tubes containing BF3 gas, 10B linings, and/or 10B-loaded polyvinyl toluene (PVT). The reaction rate for each plug-in design was also verified using forward PENTRAN and MCNP5 calculations. In addition to the equivalent designs, the adjoint method also yielded various insights into neutron detector design that can lead to additional designs using a combination of different detector materials such as BF3/10B-loaded PVT, 10B-lined tubes/10B-loaded PVT, etc.

Download or read book Measurement of Neutron Flux and Spectra for Physical and Biological Applications written by National Committee on Radiation Protection and Measurements (U.S.) and published by . This book was released on 1960 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Ultrafast Neutron Detector written by and published by . This book was released on 1987 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The invention comprises a neutron detector (50) of very high temporal resolution that is particularly well suited for measuring the fusion reaction neutrons produced by laser-driven inertial confinement fusion targets. The detector comprises a biased two-conductor traveling-wave transmission line (54, 56, 58, 68) having a uranium cathode (60) and a phosphor anode (62) as respective parts of the two conductors. A charge line and Auston switch assembly (70, 72, 74) launch an electric field pulse along the transmission line. Neutrons striking the uranium cathode at a location where the field pulse is passing, are enabled to strike the phosphor anode and produce light that is recorded on photographic film (64). The transmission line may be variously configured to achieve specific experimental goals.

Download or read book Handbook of Particle Detection and Imaging written by Claus Grupen and published by Springer Science & Business Media. This book was released on 2012-01-08 with total page 1251 pages. Available in PDF, EPUB and Kindle. Book excerpt: The handbook centers on detection techniques in the field of particle physics, medical imaging and related subjects. It is structured into three parts. The first one is dealing with basic ideas of particle detectors, followed by applications of these devices in high energy physics and other fields. In the last part the large field of medical imaging using similar detection techniques is described. The different chapters of the book are written by world experts in their field. Clear instructions on the detection techniques and principles in terms of relevant operation parameters for scientists and graduate students are given.Detailed tables and diagrams will make this a very useful handbook for the application of these techniques in many different fields like physics, medicine, biology and other areas of natural science.

Download or read book Neutron Generators for Analytical Purposes written by International Atomic Energy Agency and published by IAEA Radiation Technology Repo. This book was released on 2012 with total page 145 pages. Available in PDF, EPUB and Kindle. Book excerpt: This publication addresses recent developments in neutron generator (NG) technology. It presents information on compact instruments with high neutron yield to be used for neutron activation analysis (NAA) and prompt gamma neutron activation analysis in combination with high count rate spectrometers. Traditional NGs have been shown to be effective for applications including borehole logging, homeland security, nuclear medicine and the on-line analysis of aluminium, coal and cement. Pulsed fast thermal neutron analysis, as well as tagged and timed neutron analysis, are additional techniques which can be applied using NG. Furthermore, NG can effectively be used for elemental analysis and is also effective for analysis of hidden materials by neutron radiography. Useful guidelines for developing NG based research laboratories are also provided in this publication.

Download or read book Neutron Detectors written by International Atomic Energy Agency and published by . This book was released on 1966 with total page 436 pages. Available in PDF, EPUB and Kindle. Book excerpt: A child speculates about sleeping next to various animals in various places other than one's own, and most desirable, warm bed.

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 456 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.

Download or read book A Precision Neutron Detector for p n Reaction Measurements written by Rajat Kudchadker and published by . This book was released on 1992 with total page 180 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Fusion Neutronics written by Yican Wu and published by Springer. This book was released on 2017-08-16 with total page 402 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a systematic and comprehensive introduction to fusion neutronics, covering all key topics from the fundamental theories and methodologies, as well as a wide range of fusion system designs and experiments. It is the first-ever book focusing on the subject of fusion neutronics research. Compared with other nuclear devices such as fission reactors and accelerators, fusion systems are normally characterized by their complex geometry and nuclear physics, which entail new challenges for neutronics such as complicated modeling, deep penetration, low simulation efficiency, multi-physics coupling, etc. The book focuses on the neutronic characteristics of fusion systems and introduces a series of theories and methodologies that were developed to address the challenges of fusion neutronics. Further, it introduces readers to the unique principles and procedures of neutronics design, experimental methodologies and methodologies for fusion systems. The book not only highlights the latest advances and trends in the field, but also draws on the experiences and skills collected in the author’s more than 40 years of research. To make it more accessible and enhance its practical value, various representative examples are included to illustrate the application and efficiency of the methods, designs and experimental techniques discussed.

Download or read book Neutron Detectors for Scattering Applications written by Yacouba Diawara and published by Springer Nature. This book was released on 2023-08-04 with total page 257 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book covers the most common neutron detectors used in neutron scattering facilities and all of those in use at Oak Ridge National Lab. It starts describing the facilities, instruments and the critical detector parameters needed by various instruments. Then the key components of the 3He-based linear position-sensitive detectors as well as on their electronics, which require particular attention to signal processing and noise reduction, are introduced. One chapter is dedicated to the 3He alternatives where scintillators play a critical role. It also covers emerging neutron detection technologies including semiconductors, vacuum-based devices and their associated readouts, which will be required in the future for high rate and high-resolution neutron detectors. The authors explain the logic behind the choice of materials as well as the various constraints that neutron detectors must respect to be useful. Some of these constraints, such as efficiency and gamma-ray sensitivity are common to all neutron counters while others, like timing resolution, dynamic range, and peak counting rate, depend on the applications. The book guides experts, the nuclear science community, and young scholars through the physical processes and the required electronics in a way that is accessible for those not professionally involved in designing detector’s components and electronic circuits.

Download or read book Elements of Slow Neutron Scattering written by J. M. Carpenter and published by Cambridge University Press. This book was released on 2015-09-24 with total page 539 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a comprehensive and up-to-date introduction to the fundamental theory and applications of slow-neutron scattering.