Volume 436, Number 3, June IV 2005
|Page(s)||1123 - 1130|
|Section||Atomic, molecular, and nuclear data|
|Published online||03 June 2005|
Atomic data from the Iron project
LVII. Radiative transition rates and collision strengths within the 3d configuration of Ni IV
Centro de Física, Instituto Venezolano de Investigaciones Científicas (IVIC), PO Box 21827, Caracas 1020A, Venezuela e-mail: [mmelende;mbautist]@ivic.ve
Accepted: 1 February 2005
This paper reports on radiative transition rates and electron impact excitation rate coefficients for levels of the 3d7 ground configuration of Ni iv. The radiative data were computed using the Thomas-Fermi-Dirac central potential method, which allows for configuration interactions (CI) and relativistic effects in the Breit-Pauli formalism. Collision strengths in LS-coupling were calculated in the close coupling approximation with the R-matrix method. Then, fine structure collision strengths were obtained by means of the intermediate-coupling frame transformation (ICFT) method that accounts for spin-orbit coupling effects. The collision strengths were integrated over a Maxwellian distribution of electron energies, and the resulting effective collision strengths are given for a wide range of temperatures. We build a multilevel model for the Ni iv system and use it to identify the most important lines in optical and infrared spectra and to compute line ratios as diagnostics of nebular conditions. Finally, we test these data against recent observations of the bipolar planetary nebula Mz 3.
Key words: atomic data / atomic processes / line: formation / ISM: HII regions / ISM: planetary nebulae: general / ISM: planetary nebulae: individual: Mz 3
© ESO, 2005
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.