Schematic Description (IMAGE) University of California - Riverside Caption A schematic description of the experimental anomaly that Tanedo and his colleagues have investigated. Excited beryllium-8 nuclei can decay into their ground state while emitting electron-positron pairs. The results of the experiment suggest the presence of a new force particle, here labelled as X. Credit UC Riverside Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.