2011/01/31 by Th. A. Mueller, D. Lhuillier, M. Fallot +9 · 6 citations
Physics and Astronomy · #Advanced Chemical Physics Studies #Neutrino Physics Research #Particle physics theoretical and experimental studies #hep-ex #nucl-ex
paper · pdf · doi:10.1103/physrevc.83.054615
published as Phys.Rev.C83:054615,2011 · 17 pages, 12 figures. Submitted to Phys. Rev. C
arxiv created 2011/03/11 · openalex publication_date 2011/05/23 · arxiv updated 2015/03/17 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/01
Precise predictions of the antineutrino spectra emitted by nuclear reactors is a key ingredient in measurements of reactor neutrino oscillations as well as in recent applications to the surveillance of power plants in the context of nonproliferation of nuclear weapons. We report new calculations including the latest information from nuclear databases and a detailed error budget. The first part of this work is the so-called ab initio approach where the total antineutrino spectrum is built from the sum of all \ensuremathβ branches of all fission products predicted by an evolution code. Systematic effects and missing information in nuclear databases lead to final relative uncertainties in the 10--20% range. A prediction of the antineutrino spectrum associated with the fission of 238U is given based on this ab initio method. For the dominant isotopes we developed a more accurate approach combining information from nuclear databases and reference electron spectra associated with the fission of 235U, 239Pu, and 241Pu, measured at Institut Laue-Langevin (ILL) in the 1980s. We show how the anchor point of the measured total \ensuremathβ spectra can be used to suppress the uncertainty in nuclear databases while taking advantage of all the information they contain. We provide new reference antineutrino spectra for 235U, 239Pu, and 241Pu isotopes in the 2--8 MeV range. While the shapes of the spectra and their uncertainties are comparable to those of the previous analysis of the ILL data, the normalization is shifted by about +3% on average. In the perspective of the reanalysis of past experiments and direct use of these results by upcoming oscillation experiments, we discuss the various sources of errors and their correlations as well as the corrections induced by off-equilibrium effects.