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Members focus on the dissemination of knowledge and information in the area of power reactors with particular application to the production of electric power and process heat. The division sponsors meetings on the coverage of applied nuclear science and engineering as related to power plants, non-power reactors, and other nuclear facilities. It encourages and assists with the dissemination of knowledge pertinent to the safe and efficient operation of nuclear facilities through professional staff development, information exchange, and supporting the generation of viable solutions to current issues.
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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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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.
Antoaneta Roca, Yuan-Hao Liu, Ray Moss, Finn Stecher-Rasmussen, Sander Nievaart
Nuclear Technology | Volume 168 | Number 1 | October 2009 | Pages 29-34
Detectors | Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (Part 1) / Radiation Protection | doi.org/10.13182/NT09-A9096
Articles are hosted by Taylor and Francis Online.
The neutron and gamma dose in boron neutron capture therapy (BNCT) can be determined by using ionization chambers of different materials. However, inexplicable results, such as negative doses, are sometimes obtained. Computer simulations using MCNPX can help one to understand the behavior of ionization chambers. This paper deals with a part of this investigation: the contribution of protons to the total measured charge in a tissue equivalent (TE) ionization chamber that is flushed with methane-based TE gas. The inherent problem is that the Monte Carlo code MCNPX cannot track protons below 1 MeV.A custom-made program, called Proton Produced Ionization Chamber Charge (PPICC), calculates the deposited energy and thus the charge in the TE gas per proton. For this, it uses the stopping powers for protons in TE plastic and gas. MCNPX provides the total number of protons produced by all neutron interactions near the gas. To check this new procedure, measurements and simulations have been performed using a validated mixed beam of neutrons and gammas. The neutron fluence consists of 12% fast neutrons and 87% epithermal neutrons. In one setup the chamber is free-in-air (epithermal/fast neutron field) and in the other is in a cubic polymethylmethacrylate phantom at 25 mm depth (thermal/epithermal neutron field).The total charge is the sum of the charges due to electrons, originating from primary and neutron-induced gammas, and protons from 1H(n,n)1H and 14N(n,p)14C reactions. The total measured and calculated charges in the two setups have acceptable uncertainties and are in good agreement. The charge collected in a TE ionization chamber can be simulated in a mixed field of neutrons and gammas. The charge resulting from proton recoil in the gas is unexpectedly large.
