Two-step laser excitation of the even parity 5p(1/2)np and nf J=1, 2 Rydberg levels of neutral tin

We report new experimental data on the even parity 5p(1/2)np and nf J = 1, 2 Rydberg series of tin excited from the 5p6s(3/2, 1/2)(1) intermediate lev el using a two-step laser excitation technique in conjunction with an atomi c beam apparatus. The Rydberg series 5pnf(1/2, 5/2)(2) (12 less than or equ al to n less than or equal to 46) and 5pnp(1/2, 1/2)(1) (20 less than or eq ual to n less than or equal to 31) are reported for the first time, whereas the 5pnp(1/2, 3/2)(2) (16 less than or equal to n less than or equal to 56 ) series have been extended to higher principal quantum number. The previou sly reported three p levels, 5p8p(3/2, 3/2)(0,2) and 5p8p(3/2, 1/2)(2), and three f levels, 5p5f(3/2, 5/2)(1/2) and 5p5f(3/2, 7/2)(2), have also been detected. The inter-channel interaction among the 5pnf(1/2, 5/2)(2) and 5p5 f(3/2, 5/2)(2) channels has been studied using a two channel quantum defect theory.