Spin-orbit-interaction activated interchannel coupling in dipole and quadrupole photoionization

Abstract

The effect of spin-orbit interaction activated interchannel coupling in dipole and quadrupole photoionization of the $4p$ and $4d$ subshells of Xe and the $5p$ and $5d$ subshells of Rn using the relativistic random phase approximation (RRPA) is studied. Interference between channels arising from spin-orbit split components is found to influence the dipole cross sections of $\text{Xe}\text{ }4d$ and $\text{Rn}\text{ }5d$ subshells, and also the quadrupole cross sections of $\text{Xe}\text{ }4p$ and $\text{Rn}\text{ }5p$ subshells. The photoelectron angular distribution parameters are also affected, but to a lesser extent. Using the understanding gained, the conditions required for large spin-orbit interaction activated interchannel coupling effects are delineated.