1. Direct Observation of the Spontaneous Emission of the Hyperfine Transition F = 4 to F = 3 in Ground State Hydrogenlike 165Ho66+ in an Electron Beam Ion Trap Savin, Daniel Wolf; Lopez-Urrutia, Jose R. Crespo; Beiersdorfer, P.; Widmann, Klaus 1996 Articles AstrophysicsPlasma (Ionized gases)Physics