  Measurements of the decay energy released as a function of time following the
thermal neutron induced fission on $^{235}$U and $^{239,241}$Pu were performed
in the 1970s at Oak Ridge National Laboratory with the purpose of quantifying
possible Loss Of Coolant Accident scenarios. This decay energy, known in
technical parlance as decay heat, is mainly composed of two terms, that of the
electrons produced together with antineutrinos in the beta-minus decay of the
neutron-rich fission products, and that of the gammas produced in the
subsequent decay of excited nuclear levels. In this work we study if this
extensive set of decay heat measurements can be used to assess the Reactor
Antineutrino Anomaly, that is, the approximately 5\% deficit of electron
antineutrinos produced by nuclear reactors, first deduced by Mention and
collaborators in 2011, and observed by the major reactor antineutrino
experiments near nuclear power plants since. With the assistance of nuclear
databases, we are able to obtain the ratio of electron spectra under
equilibrium conditions for $^{235}$U to $^{239}$Pu, in better agreement with
the lower trend recently reported by Kopeikin and collaborators, as well as
those for $^{235}$U to $^{241}$Pu and $^{241}$Pu to $^{239}$Pu, which do not
agree well with those measured at the Insitut Laue-Langevin in the 1980s. We
conclude that a new experimental campaign is needed to measure the electron
spectra utilizing a high-resolution and signal-to-noise-ratio electron
spectrometer and a highly precise fission normalization procedure.

Nuclear Experiment;Nuclear Theory