Improved values for the characteristics of prompt-fission gamma-ray spectra from the reaction U-235(n(th), f)
Journal article, 2013

In this paper we present results from measurements of prompt gamma rays from the thermal neutron induced fission of U-235. Photons were measured in coincidence with fission fragments with cerium-doped LaCl3 and LaBr3 as well as CeBr3 scintillation detectors, which offer an intriguing combination of excellent timing resolution and good resolving power. The spectra measured with all employed detectors are in excellent agreement with respect to their shapes. Characteristic parameters were extracted for a gamma-energy range from 0.1 to 6.0 MeV and the results obtained with several detectors were averaged. From that, the average emission yield of prompt-fission gamma rays was determined to be (nu) over bar (gamma) = (8.19 +/- 0.11) per fission, the average energy per photon to be epsilon(gamma) = (0.85 +/- 0.02) MeV, and the total energy to be E-gamma,E-tot = (6.92 +/- 0.09) MeV. The uncertainties are much lower than the 7.5% requested for the modeling of advanced nuclear reactor cores. Estimating the influence of gamma rays with energies between 6 and 10 MeV on the values determined in this work revealed a negligible deviation of the order of the found uncertainties.

Author

Andreas Oberstedt

Chalmers, Applied Physics, Subatomic Physics

T. Belgya

Hungarian Academy of Sciences

Robert Billnert

Chalmers, Applied Physics, Subatomic Physics

R. Borcea

EU Joint Research Centre (JRC)

T. Brys

EU Joint Research Centre (JRC)

W. Geerts

EU Joint Research Centre (JRC)

A. Gook

Technische Universität Darmstadt

F. J. Hambsch

EU Joint Research Centre (JRC)

Z. Kis

Hungarian Academy of Sciences

T. Martinez

Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas (Ciemat)

S. Oberstedt

EU Joint Research Centre (JRC)

L. Szentmiklosi

Hungarian Academy of Sciences

K. Takacs

Hungarian Academy of Sciences

M. Vidali

EU Joint Research Centre (JRC)

Physical Review C - Nuclear Physics

0556-2813 (ISSN) 1089-490X (eISSN)

Vol. 87 5 Art. no. 051602- 051602

Subject Categories

Subatomic Physics

DOI

10.1103/PhysRevC.87.051602

More information

Latest update

9/6/2018 1