The CHIANTI database consists of the following primary ASCII files for this ion:

al_2.elvlc (energy levels)

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

 
%observed energy levels: NIST database (http://physics.nist.gov/cgi-bin/AtData/main_asd)
%theoretical energy levels: Aggarwal, K.M., & Keenan, F.P., 1998, J.Phys.B, 31, 4545
%comment: Aggarwal & Keenan give only LS state energies
% produced as part of the Arcetri/Cambridge/NRL 'CHIANTI' atomic data base collaboration
%
% P.R. Young - 27-May-03
 

al_2.wgfa (radiative data)

contains wavelengths, gf and A values of the transitions. The wavelengths are based on the experimental energy levels and should be the best available. Wavelengths calculated from the theoretical energies are of an indeterminate accuracy and their values are presented as negative values of the calculated wavelength.

 
%observed energy levels: NIST database (http://physics.nist.gov/cgi-bin/AtData/main_asd)
%A-values (1-5, 3-4, 1-4): Zou, Y., Froese Fischer, C. 2001, J.Phys.B 34, 915
%A-values (1-3): Trabert, E., Wolf, A., Linkemann, J., Tordoir, X., 1999, J.Phys.B, 32, 537
%A-values (all other transitions): Young, P.R., SSTRUCT calculation for CHIANTI
%comment: The 1-3 A-value is an experimental value with error bars: (3.28+/-0.10)*10^3 s^-1.
%comment: The SSTRUCT model incorporated 50 configurations with n up to 5. Observed energy 
   levels were used to derive the A-values. f-values were compared with those of Tayal & Hibbert 
   (1984, J.Phys.B, 17, 3835) for singlet-singlet transitions and good agreement was found.
   Note that Tayal & Hibbert only gave LS A-values, and so these could not be used for CHIANTI.
% produced as part of the Arcetri/Cambridge/NRL 'CHIANTI' atomic data base collaboration
%
% P.R. Young - 23-May-03

al_2.splups (electron collision data)

contains the spline fits to the electron collision strengths scaled according the rules formulated by 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.

 

%filename: al_2.splups
%effective collision strengths: Aggarwal, K.M., & Keenan, F.P., 1994, J.Phys.B, 27, 5321
%effective collision strengths between triplet states: Aggarwal, K.M., & Keenan, F.P., 1998, J.Phys.B, 31, 4545
%gf-values (transitions 1-5, 1-18, 2-7, 3-7, 4-7, 5-6, 6-18): Aggarwal, K.M., & Keenan, F.P., 1994, J.Phys.B, 27, 2343
%gf-values (remaining transitions): P.R.Young, 2003, SSTRUCT calculation (see .wgfa file)
%theoretical energies: Aggarwal, K.M., & Keenan, F.P., 1998, J.Phys.B, 31, 4545
%theoretical energies: Aggarwal, K.M., & Keenan, F.P., 1994, J.Phys.B, 27, 5321 (except for transitions within multiplets where observed level splitting was used)
%comment: Only transitions involving levels 1-4 and 6 were fitted, as these are the only levels with significant population at astrophysical densities.
% produced as part of the Arcetri/Cambridge/NRL 'CHIANTI' atomic data base collaboration
%
%  P.R. Young - 27-May-03

al_2.splups (proton collisional data) Not available in this VERSION.

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The html table below contains the radiative data of the brightest lines sorted in wavelength

al_2_table.html (html table)


Last revised by G. Del Zanna on 4-Sep-2009