Two-color two-step photoionization optogalvanic spectroscopy was performed using high-repetition-rate titanium sapphire lasers and a uranium hollow cathode lamp to find the two-step resonance ionization schemes of uranium. Many ionization transitions were observed by exciting uranium atoms in a ground state into five, even parity, excited levels with the first-step laser and by scanning the second-step laser wavelengths. By blocking the first-step laser, single-color, two-photon ionization transitions were also identified. From these results, we have found more than 50 odd-parity autoionizing levels of uranium in the energy, ranging from the ionization potential (49958.4cm⁻¹) to 51 150cm⁻¹. The determined energy levels are within ∼1cm⁻¹ of previously reported values.

使用高重复率钛蓝宝石激光器和铀空心阴极灯进行双色两步光电离光电光谱，以寻找铀的两步共振电离方案。通过用第一步激光将基态铀原子激发到五个偶数激发能级并通过扫描第二步激光波长，观察到许多电离跃迁。通过阻挡第一步激光，还发现了单色、双光子电离跃迁。从这些结果中，我们在能量中发现了超过 50 个奇数自电离水平的铀，范围从电离势 (49958.4cm ^-1 ) 到 51 150cm ^-1。确定的能级在 ∼1cm ^-1以内 先前报告的值。