ASTROPHYSICS

ASTROPHYSICS

ASTROPHYSICS

ASTROPHYSICS

 

Spectral line lists

For convenience of users, a list of spectral lines with intensities has been produced. This list may serve primarily as a quick guide to identify lines in an observed spectrum and to recognize the most important lines at a given temperature. This list should not be used to produces specific emissivity codes, nor should it be used in systematic spectral analyses. Remember that in practical cases there is also continuum emission, abundances may differ, there may be multi-temperature structure, demsity effects, deviations from collisional ionization equilibrium, etc. With these caveats the following list is given. The original line list (given here only for comparison reasons for those who have used it before) was calculated many years ago and has for some lines less accuracy at paticular temperatures. The new line list (recommended to be used) is given here and described shortly below: new line list. The new list of lines is calculated with the following restrictions/conditions:

  • Collision ionization equilibrium, zero density limit
  • Ionization balance Arnaud & Raymond (1992) for Fe, Arnaud & Rothenflug (1985) for the others; charge transfer reactions: Arnaud & Rothenflug
  • Abundances: Lodders (2003). We adopted the proto-solar values (in general more accurate than the photospheric values, but in most cases consistent), except for He (slightly enhanced in the solar photosphere due to element migration at the bottom of the convection zone).
  • unresolved dielectronic satellites are merged into the main line (the old list had them separately)
  • temperature grid logarithmic with steps of 0.2 from 104 to 109 K
  • logarithmic emissivities are given as follows. Listed for each line is -log(Q) where
  • Q=P/(ne nH), with P the power per unit volume, and Q is in units of  10-36 W m3 (10-23 erg cm3/s) the temperature Tmax of maximum emissivity as well as -log(Qmax) is also given.

 

CIE/Mekal model documentation

An X-ray spectral code for optically thin plasmas (Updated version 2.0 12-03-1992, 56 pages)

Update of MEKA: MEKAL (7 pages)

 

Other References

Arnaud, M., Rothenflug, R., 1985, A&A Supp 60, 425

Lodders, K., 2003, ApJ 591, 1220

 



SCROLL TO TOP