Fe XII - VERSION 4.0

The CHIANTI database consists of 4 primary ASCII files for each ion in the database.

• fe_12.elvlc (energy levels)

  contains the energy levels in cm^(-1) It includes both experimental data and theoretical values of the levels energies.

  References:

  %observed energy levels: (2-4,9,11-13) Jupen, Isler & Trabert, 1994, MNRAS, 264, 627
  %observed energy levels: Corliss & Sugar, 1982, J.Phys.Chem.Ref.Data, 11, 135
  %theoretical energy levels: Binello, A.M., Landi, E., Mason, H.E., Storey, P.J., Brosius, J.W., 2001, A&A, 370, 1071
  %comment: The third column of energies denotes energies "rescaled" from the output
     of "superstructure". The 24 configuration model used to derive the transition
     probabilities in the ".wgfa" file, gave energy levels which were slightly
     different from the observed levels. A way of estimating this difference
     for the 3s2 3p2 3d levels is to take all the levels with the same parent
     configuration (i.e., the term in brackets, e.g., (3P), (1D)), and average
     the difference between the observed and theoretical level. For the levels
     for which we don't have observed energies, we subtract the averaged
     difference for the particular parent configuration.
     The energies so derived by this method are expected to be accurate to
  

  
  

• fe_12.wgfa (radiative data)

  contains wavelengths, gf and A values for each transition. Wavelengths are based on experimental level energies where available; wavelengths calculated from theoretical energies are less accurate and are given as negative values.

  References:

  %observed energy levels: (2-4,9,11- 13) Jupen, Isler & Trabert, 1994, MNRAS, 264, 627
  %observed energy levels: Corliss & Sugar, 1982, J.Phys.Chem.Ref.Data, 11, 135
  %theoretical energy levels: Binello, A.M., Landi, E., Mason, H.E., Storey, P.J., Brosius, J.W., 2001, A&A, 370, 1071
  %Radiative data: Binello, A.M., Landi, E., Mason, H.E., Storey, P.J., Brosius, J.W., 2001, A&A, 370, 1071
  %comment: the gf and A values in fourth and fifth column, respectively, have been computed by
     SuperStructure using a 24 configuration model with 4s,4p,4d,4f correlation
     (Hydrogenic) orbitals. The theoretical values so obtained have been rescaled using
     experimental and "corrected" energy levels (see ".elvlc" file).
  %comment: the addition of the M2 component to the E1 A values did not introduce any change in
     the actual figures contained in this file, due to their limited precision of three
     decimal figures, except for two transitions, 3 - 18 (A(E1)=4.991E+03, A(M2)=7.3197E-01)
     and 3 - 23 (A(E1)=7.271E+03, A(M2)=4.3539E+01). For them A=A(E1)+A(M2) has been given.
  %produced as part of the Arcetri/Cambridge/NRL 'CHIANTI' atomic data base collaboration
  %
  % A.M.Binello and E.Landi 1998
  

  
  

• fe_12.splups (electron collision data)

  contains the spline fits to the electron collision strengths scaled according to Burgess and Tully (1992). Accurate replication of the temperature averaged collision strength over a wide range of temperatures can be accomplished with the data in this file.

  References:

  
  %filename: fe_12.splups
  %collision strengths (1-5): Tayal, Henry & Pradhan 1987, ApJ, 319, 951
  %collision strengths (6-41): Flower, 1977, A&A, 54, 163
  %comment: The collision strengths for levels 37 and 40 were mis-assigned
     in Flower's paper (compare the 2D5/2 - 2P3/2 and 2F5/2 - 2P3/2
     transitions). This has been corrected here.
  %comment: The gf values were not given in Flower's paper, so a 4 configuration
     "superstructure" model was used to derive them.
  %comment: effective collision strengths were provided in the temperature range 5.6 < Log T < 6.5
  %produced as part of the Arcetri/Cambridge/NRL 'CHIANTI' atomic data base collaboration
  %
  % A.M.Binello and E. Landi 1998
  

  
  

• fe_12.psplups (electron collision data)

  contains the spline fits to the scaled proton collision strengths.

  References:

  
  %filename: fe_12.psplups
  %rates: Landman, D.A., 1978, ApJ 220, 366
  %energies: Landman, D.A., 1978, ApJ 220, 366
  %comment: Errors (comparing original rates with those derived from the above 
      splines) are at most 2\% for individual points. For transition 3-4, 
      a good fit could not be found, likely implying errors in the original 
      data values. Errors of up to 4.5\% are found for this transition.
  %produced as part of the Arcetri/Cambridge/NRL 'CHIANTI' atomic data base collaboration
  %
  % P.R.Young - Jun 2001
  

The html tables below contain the radiative data of all the lines sorted in wavelength