Improvement in a Hydrogen Maser by a New State Selection

The improvement in a hydrogen maser operation by a new state selection is described. The new state selection in which the Majorana transition is used is carefully designed about the beam optics and the reverse magnetic field in order to effectively eliminate the undesirable atoms for a maser oscillation. The efficiency of the state selection is improved to the extent of 90-percent elimination of undesirable atoms and high-performance operation is attained. In this operation, the magnetic inhomogeneity shift is reduced to about one tenth of that observed in the conventional state selection.