| Recently new reactor antineutrino spectra have been provided for 235U, 239Pu, 241Pu and 238U, increasing the mean flux by about 3 percent. To good approximation, this reevaluation applies to all reactor neutrino experiments. The synthesis of published experiments at reactor-detector distances <100 m leads to a ratio of observed event rate to predicted rate of 0.979(0.029). With our new flux evaluation, this ratio shifts to 0.937(0.027), leading to a deviation from unity at 98.4% C.L. which we call the reactor antineutrino anomaly. The compatibility of our results with the existence of a fourth non-standard neutrino state driving neutrino oscillations at short distances is discussed. The combined analysis of reactor data, gallium solar neutrino calibration experiments, and MiniBooNE-neutrino data disfavors the no-oscillation hypothesis at 99.93% C.L. The oscillation parameters are such that |Delta m_{new}^2|>1.5 eV^2 (99%) and sin^2(2\theta_{new})=0.17(0.1) (95%). Constraints on the theta13 neutrino mixing angle are revised. |
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