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.
Explore membership for yourself or for your organization.
Conference Spotlight
2026 ANS Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
Latest Magazine Issues
Mar 2026
Jan 2026
Latest Journal Issues
Nuclear Science and Engineering
April 2026
Nuclear Technology
February 2026
Fusion Science and Technology
Latest News
Going Nuclear: Notes from the officially unofficial book tour
I work in the analytical labs at one of Europe’s oldest and largest nuclear sites: Sellafield, in northwestern England. I spend my days at the fume hood front, pipette in one hand and radiation probe in the other (and dosimeter pinned to my chest, of course). Outside the lab, I have a second job: I moonlight as a writer and public speaker. My new popular science book—Going Nuclear: How the Atom Will Save the World—came out last summer, and it feels like my life has been running at full power ever since.
S. G. Carpenter, J. M. Gasidlo, J. M. Stevenson
Nuclear Science and Engineering | Volume 49 | Number 2 | October 1972 | Pages 236-239
Technical Note | doi.org/10.13182/NSE72-2
Articles are hosted by Taylor and Francis Online.
The effective delayed-neutron fractions of 235U and 239Pu have been determined for two fast critical assemblies from measurements of the absolute fission rate and the apparent reactivity worths of a calibrated 252Cf neutron source. The experimental values of βeff for the two fissile isotopes, 0.0078 to 0.00233, respectively, are in reasonable agreement with calculations. The results do not explain the 30% discrepancy in measured and calculated reactivity values in fast critical experiments.