Phys.org has reported:
A new calculation may explain why gallium experiments detected fewer electron neutrinos than expected, without requiring new particles. The discrepancy, known as the gallium anomaly, involves about 20 per cent fewer neutrinos captured by gallium nuclei.
Early signs of the anomaly appeared in the mid-1990s. Neutrino physicist Carlo Giunti of Italy first clearly identified and described it in 2007.