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
Jan 2026
Jul 2025
Latest Journal Issues
Nuclear Science and Engineering
February 2026
Nuclear Technology
December 2025
Fusion Science and Technology
November 2025
Latest News
Congress passes new nuclear funding
On January 15, in an 82–14 vote, the U.S. Senate passed an Energy and Water Development appropriations bill to fund the U.S. Department of Energy for fiscal year 2026 as part of a broader package that also funded the U.S. Army Corps of Engineers and the U.S. Bureau of Reclamation.
P. I. Johansson, B. Holmqvist
Nuclear Science and Engineering | Volume 62 | Number 4 | April 1977 | Pages 695-708
Technical Paper | doi.org/10.13182/NSE77-A15210
Articles are hosted by Taylor and Francis Online.
The prompt fission neutron spectrum emitted by a sample of 235U irradiated with 0.53-MeV neutrons has been measured in the 0.6- to 15-MeV energy range by using time-of-flight (TOF) techniques. In the present work, a major effort was made to obtain an accurate experimental determination of the energy response and efficiency function of the neutron detector over the entire neutron energy range of interest. For this purpose, the TOF spectrometer was calibrated with respect to energy in the 0.5- to 21-MeV range by observing neutron groups from various nuclear reactions. The energy dependence of the neutron detector efficiency was determined by observing the angular distributions of the H(n,n)H process in the 1- to 15-MeV energy range. The overlapping 0.6- to 3-MeV energy range was covered by the T(p,n)3He reaction. The result of the fission neutron spectrum measurements has been used to find a suitable distribution function describing the data in the entire energy interval. The best description was obtained with the distribution N1(E) exp(–1.02E)sinh(2.32E)1/2.
