Theoretical calculations of dielectronic recombination in crossed electric and magnetic fields

Abstract

Recently, Robicheaux and Pindzola [Phys. Rev. Lett. 79, 2237 (1997)] reported on model calculations of dielectronic recombination (DR) in the presence of crossed electric and magnetic fields. They showed that the enhancement of the DR by an electric field may be increased further when a magnetic field perpendicular to the electric field is present in the collision region. In this paper, we describe the results of distorted-wave calculations of dielectronic recombination in the presence of crossed electric and magnetic fields for Li-like C${}^{3+}$ and Si${}^{11+}$. Two sets of calculations are performed and compared. The first is based on a full intermediate-coupling (IC) calculation, while the second is based on a much simpler configuration-average (CA) approximation. Both sets of calculations predict substantial added enhancement of DR due to the magnetic field. However, the CA approximation overestimates the field-enhanced DR as compared to both the IC calculations and previous measurements of total recombination. Comparisons of our IC results with total recombination measurements are not possible because the IC Hamiltonian matrices are too large for the high values of $n$ included in these experiments; however, in anticipation of possible high-resolution experimental studies of partial DR in fields, we report on an IC calculation of the crossed-fields enhancement of DR as a function of electric-field strength for $n$=24 in Si${}^{11+}$.