Measurement of the K?2/K?1 ratio in heliumlike krypton

We report the measurement of the K{beta}{sub 2}/K{beta}{sub 1} ratio of He-like krypton using the SuperEBIT electron beam ion trap at the Lawrence Livermore National Laboratory. The energy of these lines are about 15 keV, which is twice as high as the energy of such lines measured before. A comparison with theoretical predictions shows poor agreement, concerning the trend uncovered earlier where the measured result is considerably larger than predicted.