Versions 1.3 and 2.0 are maintained as archives.
For Version 3.0, the database management system has been completely replaced by a relational database management system. This assures a high level of consistency and integration of the data, as for example for the information on the lines and levels of an atom.
A new version of the interface has been developed. The interface for the return pages includes direct access to the bibliographic references by clicking on links given in the tables. An advanced help system is provided with balloon explanations of various symbols and quantities.
New graphical features include dynamic transition plots (Grotrian diagrams) with ability to zoom into particular energy levels and their transitions and online generated plots for Saha/Local Thermodynamic Equilibrium (LTE) plasma emission spectra for arbitrary electron temperature and density. The Grotrian diagrams interface requires a Java2 plugin (available at java.sun.com) for the user's browser.
The data tables have been expanded to include:
Spectrum lines and energy levels for xenon in all stages of ionization Xe I-Xe LIV.
Spectrum lines and energy levels for rubidium in all stages of ionization Rb I-Rb XXXVII.
Energy levels and lines for Hg I and Hg II.
New data for the energy levels and spectral lines of Zr III and Zr IV.
New data for the energy levels and spectral lines of Ba I and Ba II.
Newly compiled data for spectrum lines and levels of Ne I.
Spectral lines from the Spectral Data for the Chandra X-ray Observatory Database for Ne V-VIII, Mg V-X, Si VI-XII, and S VIII-XIV in the range 20 Å to170 Å added to ASD.
New data for the lines and levels of Ti III-Ti XXII, V IV-V XXIII, Cr V-Cr XXIV, Mn VI-Mn XXV, Fe VII-Fe XXVI, Co VIII-Co XXVII, Ni IX-Ni XXVIII, Cu X-Cu XXIX, Kr V-Kr XXXVI, Mo VI-Mo XLII. This large body of data was taken from the compilation “Spectral Data for Highly Ionized Atoms: TI, V, Cr, Mn, Fe, Ni, Cu, Kr, and Mo,” by T. Shirai, J. Sugar, A. Musgrove, and W.L. Wiese, J. Phys. Chem. Ref. Data, Monograph 8 (2000). This volume provides data for the spectral lines of these ions. Although the energy levels relevant to each line were given, there was no separate table of energy levels in this volume. The energy values and term identifications of the levels were taken from various NIST energy level compilations, as already included in Version 2.0 of ASD. However, Monograph 8 incorporated numerous modifications to the level data that had taken place since the original NIST compilations. A detailed description of corrections and changes is available.
An error that occurred in converting wavelengths in air longer than 20000 Å taken from the NIST68 compilation to wave numbers in vacuum was corrected.
All questionable spectral lines (with wavelengths in parentheses in ASD 2.0) are removed.
All terms split into levels (e.g., one term Mg XI 1s4f 3F J=2-4 with energy  is now presented by three levels with the same energy).
In all occurrences of the 3d7 shell, the incorrect term 2D2 replaced with the correct seniority term 2D3.
Al: II IV VII X XII | Ar: I | As: I XXIV XXV XXXIII
B: I | Be: I | Br: XXVII
C: V | Ca: I | Ce: II III | Co: I VI | Cr: I IV | Cu: I III VI
F: I | Fe: III
Ga: III XVI XXII XXIV
Mg: I II XII | Mo: XXXIV
Ne: I | Ni: XIX
O: I V
S: I II III IV VII | Sc: I II IV V X XI XII XIII XV XIX | Se: XXVI | Si: II
Zn: II III
The major source of corrections/additions was the paper by V. Kaufman and W. C. Martin, J. Phys. Chem. Ref. Data 20, 775 (1991) (below referred to as KM-Al)
Incorrect lines in the 3s3p-3s3d 3P-3D multiplet are removed.
Added 8 levels for 10d, 9d, 8d, 6s (KM-Al)
Added 8 lines from those levels (KM-Al)
Added level 1598270, J=7/2 from KM-Al
Added 1 line from that level (KM-Al)
Lines 177.77 and 177.84, the energies of the lower levels were incorrect
For the 1s2-1s2p line, the transition probability was too small by a factor of 100000
The value of the level at 125736.9 cm-1 is changed to 125376.9 cm-1.
For the levels 125490.83 and 125490.74, the core should be 2P1/2 rather than 2P3/2.
Duplicate levels 72944.4 and 72501.9 removed
2 duplicate levels 16377000 removed
14 incorrectly entered levels above 15000000 removed (only those from Kelly's H-Kr compilation are left).
Duplicate limit removed
Misprint in configuration 2s23ld - should be 2s236d.
Duplicate lines 2494.583, 2494.728 removed
14 incorrectly entered levels above 16000000 removed (only those from Kelly's H-Kr compilation are left).
Energy of the 1s3s 3S was 2893573.8, corrected to 2839573.8 (misprint)
Level 48398.6 should be 3p64s11h
Level 6967.547, J=13/2, second component should be 4f5d(3Go)6p
102961.29, second basis state has had 1/2, should be 3/2
Group of levels near 55000 wrongly have the same term value of '1', should be '2'-'6'
Levels 376793.0, 378219.1, and 378740.0 should be 3d3(4P)4p
Level 52677.88 should have J=7
One of the levels 239541.4 should have J=5/2
Level 84025.1 should be 3d94s(3D2)12p3/2
Levels 293747 and 294910 should be 3d84s(4P)4p
3d5(3F2)4p should be 3d5(2F2)4p
Some levels near 35000 cm-1 were incorrectly grouped into one term '8Do?'
Incorrect J-values for 138272.0 fixed
Transition probability for the 3355.48 line was factor of 10 too small
Levels 220346.65, 220346.75, 227637.2, and 227637.2 should have core 3d10 rather than 3d9
Energy 38425 replaced by 34825 (misprint)
Configuration for the level 14045000 should be 2s2p64p
One of the energies should be 11379000 rather than 111379000
Added leading configurations for levels 12483000, 12330000, 11682000, 11557000, 11406000, 11379000
The energy levels are taken from G.W.F. Drake and W.C. Martin, Can. J. Phys 76, 679-698 (1998). Experimental values (from Table 8 of that paper) are used for 1s2s 3S1 and 1S0, 1s2p 3P2,1,0 and 1P1, 1s3s 1S0, 1s3p 3P2,1,0 and 1P1, 1s4s 3S1, and 1s5s 3S1. For all other levels, the theoretical data (Table 6) are used. The energies are rounded to 4 places.
Energy 2002900 should be 2062900 (misprint)
Number of double excited configurations have unorthodox designations:
1s.2,4.sp- --> 1s2p4s
Level 6d added
1 line added; overlap with 5d
Some revisions and
extensions of the Mg II levels as given in the 1991 wavelengths table
are also used in the levels table here. In addition, newly evaluated
positions for the quartet levels of configurations involving the
2p5(2Po) excited core are also given
in the tables here. All these quartet levels are now given with
respect to the 2p63s 2S ground level without
any unknown connection ("+x").
Wavelengths and Energy Level Classifications of Magnesium Spectra for All Stages of Ionization (Mg I through Mg XII), V. Kaufman and W. C. Martin, J. Phys. Chem. Ref. Data 20, 83-152 (1991)
(2P*)3p2(3P) 4P*5/2 483373
(2P*)3s4s(3S) 4P*5/2 487205
(2P*)3p2(3P) 4D*5/2 488587
(2P*)3s3d(3D) 4F*9/2 489383
For the lines from 7p and 8p, the energies of 1/2and 3/2 were interchanged in the list of transitions (wavelengths do correspond to correct energies).
Energy of the 2s2 2p4 (3P) 3d 2F5/2 level should be 22046000 rather than 18060000, and the wavelength of the corresponding line should be 4.536 rather than 5.536.
Transition probability for the 6402.248 line was factor of 10 too small
Level 10925000, configuration should be 2s2p64p rather than 2p2p64p
Duplicate line 1152.55 removed
Line 485.834, lower level quantum numbers were incorrect
There are a few duplicate lines (4402.104, 4417.337, 4466.140, 4530.823, 4582.180) with the same f, log(gf),S but different A. Those with A's corresponding to f are retained, others removed.
The major source of corrections/additions was the paper by V. Kaufman and W. C. Martin, J. Phys. Chem. Ref. Data 22, 279 (1993) (below referred to as KM-S)
Added two 14d, one 12d levels; 7d,8d,9d 5D with j=2,3 (KM-S)
Had wrong energies 95206 and 95189 in the line list, corrected. Also:
Line 1106 is wrong, removed
11 lines added from KM-S
Duplicate lines 8874.48 removed
Transition probability for the 2334.605 line was too large by a factor of 10000
Energy 157810.31 corrected to 157610.31 (misprint)
9 3s3p(3P)5s and 3s3p(3P)5p levels added from KM-S
41 lines added from KM-S
Line 352.347 had wrong parent term for the upper level
The main source for data corrections was V. Kaufman and J. Sugar, J. Phys. Chem. Ref. Data 17, 1679 (1989) which is below referred to as KS-Sc.
Unidentified 101 levels and 86 lines from the KS-Sc are added
Fixed misprints in line lists:
upper level: 3649.131, 6797.26, 6799.62, 6803.68, 10684.09, 8181.32, 10716.85, 12320.29, 16707.11, 23896.2, 23896.2, 25154.9, 26185.2
lower level: 5020.137, 5066.384
Removed duplicate line 2699.015
Corrected parent term for the line 17012.76
Energies of 3d7s 3D3 and two 5g levels corrected in the line lists
6 lines added
Energy of the 3s23p5(2Po3/2)6h J=4 corrected in the line list
Duplicate lines 296.16, 300.01
Duplicate lines 596.67, 595.99, 586.96, 459.396, 576.77,490.220, 449.267, 383.580, 352.556, 357.490, 342.528,337.883, 458.165, 588.03, 736.41 removed
Duplicate lines 105.145, 522.810, 505.117, 382.042, 372.507, 168.943, 138.381, 138.283, 128.247, 127.154, 105.177, 104.441, 97.875, 97.868, 97.816, 95.090, 94.861, 84.414, 84.414, 84.371, 83.958, 78.509, 78.924, 77.932, 77.895, 64.98, 64.70 removed
56 levels added from KS-Sc
2 duplicate lines removed (26.544, 26.920)
Level 4071600 added from KS-Sc
Lines 24.560, 24.791 added from KS-Sc
Levels 4880000, 4789200 (with the parent term 1P) added from KS-Sc
Lines 21.792, 21.370 added from KS-Sc
Duplicate lines 11.845, 11.377, 11.204, 10.785, 10.631, 10.443, 2.8964 removed
14 incorrectly entered levels above 14000000 removed (only those from Kelly's H-Kr compilation are left).
Line 2334.605, A-value too large by a factor of 105
Levels 138114.0 and 138117.5 should be 3d109d
3d9(2D3/2)8s should be 3d9(2D5/2)8s for E =293658.4.