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Radiation Protection & Shielding
The Radiation Protection and Shielding Division is developing and promoting radiation protection and shielding aspects of nuclear science and technology — including interaction of nuclear radiation with materials and biological systems, instruments and techniques for the measurement of nuclear radiation fields, and radiation shield design and evaluation.
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2025 ANS Annual Conference
June 15–18, 2025
Chicago, IL|Chicago Marriott Downtown
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Latest News
Webinar: MC&A and safety in advanced reactors in focus
Towell
Russell
Prasad
The American Nuclear Society’s Nuclear Nonproliferation Policy Division recently hosted a webinar on updating material control and accounting (MC&A) and security regulations for the evolving field of advanced reactors.
Moderator Shikha Prasad (CEO, Srijan LLC) was joined by two presenters, John Russell and Lester Towell, who looked at how regulations that were historically developed for traditional light water reactors will apply to the next generation of nuclear technology and what changes need to be made.
Ramamoorthy Karthikeyan, Alain Hébert
Nuclear Technology | Volume 157 | Number 3 | March 2007 | Pages 299-316
Technical Note | Fission Reactors | doi.org/10.13182/NT07-A3819
Articles are hosted by Taylor and Francis Online.
The effect of advanced resonance self-shielding models incorporated in the developmental version of the DRAGON code on estimation of reactivity coefficients of a typical CANDU-6 lattice is evaluated. The advanced self-shielding models are based on either equivalence in the dilution model or on a subgroup approach. Under equivalence in dilution models, the generalized Stamm'ler model was used with or without Riemann integration and Nordheim model. Among the subgroup approaches, the Ribon extended and the statistical self-shielding models were used. The Ribon extended self-shielding model uses mathematical probability tables, while the statistical self-shielding model uses physical probability tables. The analysis focused on four important transients, which include the fuel temperature coefficient, coolant void reactivity, pressure tube ingression, and calandria tube ingression. Four burnup stages for estimation of reactivity have been identified. To benchmark the results obtained using DRAGON, the results obtained were compared with those of MCNP5. These analyses indicated that, of all the self-shielding models, the resonance self-shielding model based on the subgroup approach using physical probability tables seems to perform well for all situations and can be recommended for CANDU-6 analyses using the code DRAGON.