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Materials Science & Technology
The objectives of MSTD are: promote the advancement of materials science in Nuclear Science Technology; support the multidisciplines which constitute it; encourage research by providing a forum for the presentation, exchange, and documentation of relevant information; promote the interaction and communication among its members; and recognize and reward its members for significant contributions to the field of materials science in nuclear technology.
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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.
Fausto Franceschini, Bojan Petrovic
Nuclear Technology | Volume 168 | Number 2 | November 2009 | Pages 431-437
Shielding | Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (Part 2) / Radiation Protection | doi.org/10.13182/NT09-A9221
Articles are hosted by Taylor and Francis Online.
International Reactor Innovative and Secure (IRIS) is an advanced pressurized water reactor with an integral primary system. It features an integral reactor vessel surrounded by a spherical steel containment 25 m in diameter. Both deterministic and Monte Carlo methods are used to characterize its radiation environment. This paper focuses on the generation of the neutron fission source that is employed as the fixed source in radiation transport calculations. To facilitate radiation shielding analysis, a technique is proposed to synthesize fission source data from the IRIS depletion history into an average and a limiting (maximum) source distribution. The average source preserves the time-integrated, spatially dependent fission neutrons and is suitable for evaluation of long-term irradiation effects, such as the radiation damage on the reactor vessel. The maximum source gives a bounding fission neutron distribution that is suitable for calculation of the maximum instantaneous dose to the personnel. Spatial and spectral effects are also taken into consideration in the source representation. Pinwise axial distributions of the neutron fission source and the associated contribution from primary fissionable isotopes have been generated to allow evaluation of neutron leakage in the critical regions, such as at the core periphery. Less detailed assemblywise axial distributions are also made available to simplify their implementation in the MCNP and TORT models. A comparison of the results obtained with the latter distributions against the reference results (employing the most detailed distribution) will show the impact of simplifications and help identify strategic features and locations where preserving the detailed information is beneficial for meeting specific shielding objectives.The judicious postprocessing and interpretation of the fission source distribution proposed by this approach make the subsequent radiation analysis practical while retaining the critical details needed to achieve high accuracy.