The GSI anomaly

Understand

Recently, an experiment at GSI Darmstadt has observed oscillating decay rates of heavy ions.

• Several controversial attempts have been made to explain this effect in terms of neutrino mixing.
• We briefly describe the experimental results, give an overview of the literature, and show that the effect cannot be due to neutrino mixing.
• If the effect survives, it could, however, be explained by hypothetical internal excitations of the mother ions (~ 10^(-15) eV).