Electron-Ion Recombination Rate Coefficients and Photoionization Cross Sections for Astrophysically Abundant Elements. XI. N V-VI and F VII-VIII for Ultraviolet and X-Ray Modeling

Astronomy and Astrophysics – Astronomy

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

5

Atomic Data, Atomic Processes, Line: Formation, X-Rays: General

Scientific paper

The inverse processes of photoionization and electron-ion recombination for hν+N V<-->N VI+e, hν+N VI<-->N VII+e, hν+F VII<-->F VIII+e, and hν+F VIII<-->F IX+e are studied in detail using a self-consistent unified method for the total electron-ion recombination. The method enables calculation of the total and level-specific recombination rate coefficients αR and αR(i), subsuming both radiative and dielectronic recombination (RR and DR). The photoionization and recombination cross sections σPI and σRC are computed using an identical wave function expansion for both processes in the close coupling approximation using the R-matrix method. The results include total and partial photoionization cross sections and recombination rate coefficients for all fine-structure levels up to n<=10, about 100 for Li-like N V and F VII with 1/2<=J<=17/2, and over 170 for He-like N VI and F VIII with 0<=J<=10. Level-specific σPI(nSLJ) and αR(T nSLJ) are calculated for the first time for these ions. The coupled-channel wave function expansions for N V and F VII consist of 17 levels of cores N VI and F VIII, respectively, and for N VI and F VIII consist of 16 levels of cores N VII and F IX, respectively. Relativistic fine structure is considered through the Breit-Pauli R-matrix method. The single-valued total αR(T) is presented over an extended temperature range for astrophysical and laboratory plasma applications. Although the total unified αR(T) for all ions agree well with the available published RR+DR rates, significant differences are noted at the DR peak for N V. Total σRC(E) and αR(E) as functions of photoelectron energy are presented for comparison with experiments. Total rates for H-like N VII and F IX are also given for completeness. The cross sections σPI and σRC include important atomic effects such as radiation damping, channel couplings, and interference of DR and RR, and should be accurate to within 10%-15%. The comprehensive data sets are applicable for ionization balance and recombination-cascade models for UV and X-ray lines.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Electron-Ion Recombination Rate Coefficients and Photoionization Cross Sections for Astrophysically Abundant Elements. XI. N V-VI and F VII-VIII for Ultraviolet and X-Ray Modeling does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Electron-Ion Recombination Rate Coefficients and Photoionization Cross Sections for Astrophysically Abundant Elements. XI. N V-VI and F VII-VIII for Ultraviolet and X-Ray Modeling, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Electron-Ion Recombination Rate Coefficients and Photoionization Cross Sections for Astrophysically Abundant Elements. XI. N V-VI and F VII-VIII for Ultraviolet and X-Ray Modeling will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1029387

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.