Atomic data from the Iron Project. XVIII. Electron impact excitation collision strengths and rate coefficients for Fe III

Department of Astronomy, The Ohio State University, Columbus, OH 43210, U.S.A.

Received: 17 January 1996
Accepted: 27 February 1996

Abstract

Collision strengths and maxwellian averaged rate coefficients have been calculated for 23 871 transitions among 219 fine structure levels, dominated by configurations , and in Fe III. Collision strengths are calculated using the R-matrix method with a 83 term close-coupling target expansion and for electron energies up to 10 rydbergs. Rate coefficients are tabulated at a wide range of temperatures at which Fe III is abundant in plasma sources. A brief discussion of the calculations and sample results are given. The present rates for Fe III are expected to find applications in spectral diagnostics of a variety of astrophysical sources.