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Fusion Energy
This division promotes the development and timely introduction of fusion energy as a sustainable energy source with favorable economic, environmental, and safety attributes. The division cooperates with other organizations on common issues of multidisciplinary fusion science and technology, conducts professional meetings, and disseminates technical information in support of these goals. Members focus on the assessment and resolution of critical developmental issues for practical fusion energy applications.
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2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Latest News
Commercial nuclear innovation "new space" age
In early 2006, a start-up company launched a small rocket from a tiny island in the Pacific. It exploded, showering the island with debris. A year later, a second launch attempt sent a rocket to space but failed to make orbit, burning up in the atmosphere. Another year brought a third attempt—and a third failure. The following month, in September 2008, the company used the last of its funds to launch a fourth rocket. It reached orbit, making history as the first privately funded liquid-fueled rocket to do so.
Xianfei Wen, Dante Nakazawa, Mat Kastner, Jason Pavlick, Haori Yang
Nuclear Technology | Volume 194 | Number 1 | April 2016 | Pages 117-125
Technical Note | doi.org/10.13182/NT15-113
Articles are hosted by Taylor and Francis Online.
Pulsed photonuclear techniques are commonly used in homeland security and nuclear safeguards applications to achieve enhanced detection sensitivity. For example, photoneutrons generated by a pulse-mode linear accelerator (linac) are commonly utilized to produce characteristic capture gamma rays for the detection of nitrogen-rich explosives. Recently, in an effort to develop innovative systems with increased sensitivity to detect diversion and prevent misuse, the authors proposed to assay used nuclear fuel for its plutonium content using a photofission technique, in support of nuclear material management in the U.S. fuel cycle.
Passive spectroscopy measurements in the presence of intense background from fission products could be very difficult. Focusing on high-energy delayed gamma rays emitted by short-lived products from photofission presents a much more promising solution. However, as discovered in this study, a commercially available standard high-purity germanium (HPGe) preamplifier can be easily saturated for tens of milliseconds after each linac pulse. This greatly reduces the live time of the system especially when the linac repetition rate is high. On the other hand, although significantly reduced by increasing the lower-level threshold, the input count rate can still easily reach 106 cps (counts per second). Developing a gamma spectroscopy system that can handle such a high count rate has been a major challenge.
In this work, a commercial HPGe preamplifier was modified to reduce the saturation time and tail time to improve its high-rate performance in a pulsed photonuclear environment. Results of the modifications were evaluated via both simulations and experiments and proven to be effective without significant degradation of energy resolution. The field-effect transistor (FET) and feedback components were first moved to the warm side to enable the modifications. The saturation time of the preamplifier following a linac pulse was greatly reduced by decreasing the value of the feedback resistor. The effect of reducing the tail time of the output signal was also studied. A traditional trapezoidal shaping approach was then employed to study the impact of the modifications on energy resolution.