“…This a 1 value corresponds to a slope in the ratio of corrected electron spectrum to uncorrected one of +6% MeV −1 . While there have been high-quality measurements of shape factors for light nuclides, most notably for 12 B obtaining an a 1 value of +0.48% MeV −1 [38], only Q-values and strength functions derived from the electron spectra from nuclides relevant to the reactor anomaly, that is, end point energies larger than 3 MeV, have been reported [39,40]. Therefore, there is no experimental evidence that will allow us to rule out an a 1 value of 0.03.…”