Autoionizing Process of the Double Rydberg State

Using five-laser resonance excitation and double time-of-flight spectroscopy, the double Rydberg states NLnl (N ≤ 66; n ≤ 85; L, 1 < 4) of Ca have been obtained. The distribution of Ca⁺ Rydberg states, which is from the autoionization of the double Rydberg state has been measured. A novel result has been observed.