Momentum images of Fragment Negative Ions (IMAGE) Tata Institute of Fundamental Research Caption Momentum images of H from H2 and D from D2 at different electron energies. The one at 4 eV for H is symmetric, while those above 14 eV are strongly asymmetric. The asymmetry in D is less pronounced and appear to change direction with change in electron energy. Credit E. Krishnakumar et al, <i>Nature Physics</i> 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.