The interpretation of N IV and Ne VII emission line ratios in the sun.
Abstract
Summary. Using new atomic data -for electron impact collision rates, the observed N Iv and Ne vIl emission line ratios in the solar transition region have been interpreted. For N Iv, the ratio I(3Pe 3P0)/I(1P0 1S ) indicates an electron density of 1.51010 for the quiet sun, while the active region results are anomalous, possibly due to blending. From the ratio !(` D `P0)/I(3Pj0 -1 1S ) in N Iv, an electron temperature of 1.0 l0 K is deduced for the quiet sun, in agreement with that expected in steady-state ionization equilibrium. For Ne vII, the ratio I(3Pj-1 lSe)!i(1F0 1S ) is an excellent electron temperature diagnostic. For the quiet sun a value of 5 10 K is found, again in agreement with that expected in steady state ionization equilibrium while higher electron temperatures are found for coronal holes (8 l0 K) and active regions (1.2 106 K). Key words: collision rates - transition region - Be sequence - plasma diagnostics -
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- October 1979
- Bibcode:
- 1979A&A....78..318D
- Keywords:
-
- Atomic Excitations;
- Electron Impact;
- Electron Transitions;
- Emission Spectra;
- Solar Spectra;
- Collision Rates;
- Coronal Holes;
- Electron Density (Concentration);
- Electron Energy;
- Neon;
- Nitrogen;
- Solar Physics;
- Electron Temperatures:Solar Active Regions;
- Electron Temperatures:Solar Coronal Holes;
- Emission Lines:Solar Transition Region