ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
Division Spotlight
Nuclear Criticality Safety
NCSD provides communication among nuclear criticality safety professionals through the development of standards, the evolution of training methods and materials, the presentation of technical data and procedures, and the creation of specialty publications. In these ways, the division furthers the exchange of technical information on nuclear criticality safety with the ultimate goal of promoting the safe handling of fissionable materials outside reactors.
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!
Latest Magazine Issues
Apr 2024
Jan 2024
Latest Journal Issues
Nuclear Science and Engineering
May 2024
Nuclear Technology
Fusion Science and Technology
Latest News
Zap Energy hits 37-million-degree electron temperatures in compact fusion device
Zap Energy announced April 23 that it has reached 1-3 keV plasma electron temperatures—roughly the equivalent of 11 to 37 million degrees Celsius—using its sheared-flow-stabilized Z-pinch approach to fusion. Reaching temperatures above that of the sun’s core (which is 10 million degrees Celsius temperature) is just one hurdle required before any fusion confinement concept can realistically pursue net gain and fusion energy.
Renato Yoichi Ribeiro Kuramoto, Adimir dos Santos, Rogario Jerez, Ricardo Diniz
Nuclear Science and Engineering | Volume 158 | Number 3 | March 2008 | Pages 272-283
Technical Paper | doi.org/10.13182/NSE06-120
Articles are hosted by Taylor and Francis Online.
A new method for absolute measurement of the effective delayed neutron fraction eff based on Rossi- experiments and the two-region model was developed at the IPEN/MB-01 Research Reactor facility. In contrast with other techniques such as the slope method, the Nelson-number method, and the 252Cf-source method, the main advantage of this new methodology is to obtain the effective delayed neutron parameters in a purely experimental way, eliminating all parameters that are difficult to measure or calculate. In this way, Rossi- experiments for validation of this method were performed at the IPEN/MB-01 facility, and with the use of the present approach, eff was measured with a 1.46% uncertainty. In addition, the prompt neutron generation time and other parameters were also obtained in an absolute experimental way. In general, the final results agree well with values from frequency analysis experiments. Comparison of theory and experiment reveals that JENDL-3.3 shows deviation for eff lower than 1%, which meets the desired accuracy for the theoretical determination of this parameter. This work supports the reduction of the 235U thermal yield, as proposed by Okajima and Sakurai.