Two-Photon Laser Spectroscopy of Autoionizing Rydberg Series of Atomic Tin

Extensive new data on the even-parity autoionization Rydberg series of neutral-tin have been observed and identified by using two-photon resonant ionization laser spectroscopy and time-of-flight detection method. Observed autoionization Rydberg series are 5pnp(3/2,1/2)_1,2, 5pnp(3/2,3/2)_1,2,3, 5pnf3/25/2_2,3, 5pnp3/27/2_3,4, and 5pnf3/23/2_1,2. The second ionization limit I₂ is obtained by fitting experimental data with the Rydberg formula. It is 63483.90±1.35cm^-1.