The article re-evaluates the flux of antineutrinos from reactors with new spectra of decays from heavy nuclei, finding that the flux is larger than previously estimated by about 3 percent, at all reactor experiments. This drives the former ratio of observed by predicted flux from 0.979+-0.029 to 0.937+-0.027: this seemingly small difference has a huge impact, because the new result is significantly smaller than one. This might be explained by being due to the existence of a sterile neutrino into which an oscillation may occur.
I am unable to comment on the paper right now, but I am sure many readers of this blog will find it highly interesting. If any of you, who is familiar with neutrino physics, wants to comment on the paper and its findings, I am more than happy to leave you the scene, with a guest post. Applications in the comments thread!