atomic data for S II

[gary]

update to

Breit-Pauli Transition Probabilities and Electron Excitation

Collision Strengths for Singly Ionized Sulfur

1. S. Tayal and O. Zatsarinny 2010 ApJS 188 32-45 Abstract: http://iopscience.iop.org/0067-0049/188/1/32 Full text PDF: http://iopscience.iop.org/0067-0049/188/1/32/pdf/apjs_188_1_32.pdf Full text HTML: http://iopscience.iop.org/0067-0049/188/1/32/fulltext

New improved calculations are reported for transition

probabilities and electron impact excitation collision strengths for the astrophysically important lines in S II. The collision strengths have been calculated in the close-coupling approximation using the B-spline Breit-Pauli R-matrix method. The multiconfiguration Hartree-Fock method with term-dependent non-orthogonal orbitals is employed for an accurate representation of the target wave functions. The close-coupling expansion includes 70 bound levels of S II covering all possible terms of the ground 3s 23p 3 and singly excited 3s3p 4, 3s 23p 23d, 3s 23p 24s, and 3s 23p 24p configurations. The present calculations are more extensive than previous ones, leading to a total 2415 transitions between fine-structure levels. The effective collision strengths are obtained by averaging the electron collision strengths over a Maxwellian distribution of velocities and these are tabulated for all fine-structure transitions at electron temperatures in the range from 5000 to 100,000 K. The present results are compared with a variety of other close-coupling calculations and available experimental data. There is an overall good agreement with the recent 18-state calculations by Ramsbottom, Bell, & Stafford and with the 19-state calculations by Tayal for the most part, but some significant differences are also noted for some transitions.

[gary]

Milestone C12 release deleted