Recombination coefficients for O II lines in nebular conditions
Abstract
We present the results of a calculation of recombination coefficients for O2++ e- using an intermediate coupling treatment that fully accounts for the dependence of the distribution of population among the ground levels of O2+ on electron density and temperature. The calculation is extended down to low electron temperatures, where dielectronic recombination arising from Rydberg states converging on the O2+ ground levels is an important process. The data that consist of emission coefficients for 8889 recombination lines and recombination coefficients for the ground and metastable states of O+ are in Cases A, B and C, and are organized as a function of the electron temperature and number density, as well as wavelength. An interactive fortran 77 data server is also provided as an accessory for mining the line emission coefficients and obtaining Lagrange interpolated values for any choice of the two variables between the explicitly provided values for any set of wavelengths. Some illustrations of the application of the new data to nebular observations are also provided.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- September 2017
- DOI:
- 10.1093/mnras/stx1189
- arXiv:
- arXiv:1703.09982
- Bibcode:
- 2017MNRAS.470..379S
- Keywords:
-
- astrochemistry;
- atomic data;
- atomic processes;
- plasmas;
- radiation mechanisms: general;
- radiation mechanisms: non-thermal;
- methods: numerical;
- H <sc>II</sc> regions;
- planetary nebulae: general;
- atomic data - atomic processes;
- H <sc>II</sc> regions - planetary nebulae: general;
- Physics - Atomic Physics;
- Astrophysics - Solar and Stellar Astrophysics;
- Physics - Computational Physics;
- Physics - Plasma Physics
- E-Print:
- 15 pages, 7 figures, 6 tables