Atomic data from the IRON Project

XXXIV. Electron impact excitation of Fe xvi

¹ Lehrstuhl für Theoretische Physik I, Ruhr-Universität, D-44780 Bochum, Germany
² Departamento de Física, Universidad Metropolitana, PO Box 76819, Caracas 1070A, Venezuela
³ UMR 8631 (associée au CNRS et à l'Université Paris 7) et DAEC, Observatoire de Paris, F-92195 Meudon, France
⁴ Centro de Física, Instituto Venezolano de Investigaciones Científicas (IVIC), PO Box 21827, Caracas 1020A, Venezuela

Send offprint request to: C.J. Zeippen

Received: 25 September 1998
Accepted: 18 November 1998

Abstract

As part of the IRON Project, electron impact excitation effective collision strengths are computed for the ion Fe xvi familiar in solar spectra. A Breit–Pauli R-matrix calculation is performed with a 12-level () target representation. The calculation for this relatively simple ion is approached as a test case where we can analyze in detail most of the effects that contribute to the accuracy of the collision strengths: the energy mesh, relativistic corrections, the asymptotic multipole potentials and contributions from high partial waves. By comparing with two recent independent calculations, an accuracy rating of 10% is assigned to the present effective collision strengths in the electron-temperature range of .