Astron. Astrophys. Suppl. Ser. 134, 369-375

Atomic data from the IRON Project

XXX. Collision data for the ²P$^{\rm o}$$_{1\over 2}$ - ²P$^{\rm o}$$_{3\over 2}$fine-structure lines of P III, S IV and Cl V

H.E. Saraph - P.J. Storey

Send offprint request: H.E. Saraph

Department of Physics and Astronomy, University College London, London WC1E 6BT, UK

Received June 8; accepted August 7, 1998

Abstract:

This is the third paper in a series giving collision rates for electron excitation of the ²P$^{\rm o}$$_{1\over 2}$ - ²P$^{\rm o}$$_{3\over 2}$ ground state fine-structure transition in aluminium-like ions. In this paper we give data for the transitions in P III (17.9 $\mu$m), S IV ($10.5~ \mu$m) and Cl V (6.71 $\mu$m). For the P and Cl ions the only existing results are nearly 30 years old and were obtained using a method which does not incorporate resonance effects. For S IV, previous close-coupling calculations do exist but we show that our more elaborate calculation changes the rate coefficients by about 50% at lower temperatures.

Key words: atomic data