2013/08/01 by M. F. R. Grieve, C. A. Ramsbottom, C. E. Hudson +1 · 2 citations
Engineering · Physics and Astronomy · #Atomic and Molecular Physics #Collision #Collisional excitation #Emission spectrum #Excitation #Ionosphere and magnetosphere dynamics #Laser-induced spectroscopy and plasma #Line (geometry) #Range (aeronautics) #Spectral line #Torus #astro-ph.SR
paper · pdf · doi:10.1088/0004-637x/780/1/110
14 pages, 8 figures, 6 tables
arxiv created 2013/08/01 · openalex publication_date 2013/12/13 · arxiv updated 2015/06/16 · openalex created_date 2019/06/27 · openalex updated_date 2026/08/05
We present Maxwellian-averaged effective collision strengths for the electron-impact excitation of S iii over a wide range of electron temperatures of astrophysical importance, log T e (K) = 3.0–6.0. The calculation incorporates 53 fine-structure levels arising from the six configurations—3 s 2 3 p 2 , 3 s 3 p 3 , 3 s 2 3 p 3d, 3 s 2 3 p 4 s , 3 s 2 3 p 4 p , and 3 s 2 3 p 4 d —giving rise to 1378 individual lines and is undertaken using the recently developed RMATRX II plus FINE95 suite of codes. A detailed comparison is made with a previous R -matrix calculation and significant differences are found for some transitions. The atomic data are subsequently incorporated into the modeling code cloudy to generate line intensities for a range of plasma parameters, with emphasis on allowed ultraviolet extreme-ultraviolet emission lines detected from the Io plasma torus. Electron density-sensitive line ratios are calculated with the present atomic data and compared with those from CHIANTI v7.1, as well as with Io plasma torus spectra obtained by Far-Ultraviolet Spectroscopic Explorer and Extreme-Ultraviolet Explorer . The present line intensities are found to agree well with the observational results and provide a noticeable improvement on the values predicted by CHIANTI.