Scaling behavior of radiative recombination cross sections and rate coefficients

Direct radiative recombination (RR) cross sections σRR and rate coefficients αRR are presented for all ions using the scaling property of the cross section in the parameter {η}=Zeff/(ka₀). The RR cross section is defined simply in terms of two parameters, {η} and the number of electrons N in the target ion. The RR rate coefficient αRR/Zeff in turn depends on two parameters, the scaled temperature (FTHETA=kBT/Zeff²) and N. An empirical formula for the effective charge Zeff is constructed, which is weakly dependent on the electron energy k². The cross-section values can also be used in analyzing high-energy ion-atom collisions with radiative electron capture.