5p_1/2nl_j autoionizing states of strontium for 0 l 5

We report a comprehensive experimental and theoretical study of the autoionization of core-excited 5p(1/2)nl(j) strontium Rydberg states for intermediate values of l(j) in the range 0 less than or similar to l(j) less than or similar to 5. For a given value of l(j) autoionization, which results from the energy exchange between the two excited valence electrons, is found to scale as similar to 1/n(3), mirroring the decrease in the Rydberg electron probability density in the vicinity of the inner 5p(1/2) electron cloud. In contrast, the l(j) dependence of the autoionization rate is more complex. For the larger values of l(j) (>= 4), the autoionization rate decreases as l(j)(-5) due to the centrifugal barrier, which prevents the Rydberg electron from penetrating the core and inner 5p(1/2) electron cloud. For the low-l(j) core-penetrating Rydberg states, the scattering phase shift induced by the effective core potential becomes important in determining both the autoionization rates, which no longer show a monotonic variation with j pound, and the quantum defects.