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Division Spotlight
Isotopes & Radiation
Members are devoted to applying nuclear science and engineering technologies involving isotopes, radiation applications, and associated equipment in scientific research, development, and industrial processes. Their interests lie primarily in education, industrial uses, biology, medicine, and health physics. Division committees include Analytical Applications of Isotopes and Radiation, Biology and Medicine, Radiation Applications, Radiation Sources and Detection, and Thermal Power Sources.
Meeting Spotlight
2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
Standards Program
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.
A. Pérez-Andújar, W. D. Newhauser, P. M. DeLuca, Jr.
Nuclear Technology | Volume 168 | Number 3 | December 2009 | Pages 728-735
Proton Therapy | Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (PART 3) / Radiation Protection | doi.org/10.13182/NT09-A9297
Articles are hosted by Taylor and Francis Online.
Proton therapy offers low integral dose and good tumor comformality in many deep-seated tumors. However, secondary particles generated during proton therapy, such as neutrons, are a concern, especially for passive scattering systems. In this type of system, the proton beam interacts with several components of the treatment nozzle that lie along the delivery path and can produce secondary neutrons. Neutron production along the beam's central axis in a double scattering passive system was examined using Monte Carlo simulations. Neutron fluence and energy distribution were determined downstream of the nozzle's major components at different radial distances from the central axis. In addition, the neutron absorbed dose per primary proton around the nozzle was investigated. Neutron fluence was highest immediately downstream of the range modulator wheel (RMW) but decreased as distance from the RMW increased. The nozzle's final collimator and snout also contributed to the production of high-energy neutrons. In fact, for the smallest treatment volume simulated, the neutron absorbed dose per proton at isocenter increased by a factor of 20 due to the snout presence when compared with a nozzle without a snout. The presented results can be used to design more effective local shielding components inside the treatment nozzle as well as to better understand the treatment room shielding requirements.