We review the spectroscopic work on atomic lines and energy levels in neutral and singly and doubly ionized iron-group elements during the past 35 years. We have graded the completeness of the analysis of these spectra and compared them with the data included in the multiplet tables of
Moore [
Natl. Bur. Stand. (U.S.) Circ. 488 (
1962);
Natl. Stand. Ref. Data Ser. Natl. Bur. Stand. 40 (
1972)]. Specific comments are given on each spectrum. We discuss new demands for atomic data resulting from high-resolution spectroscopy of peculiar stars and observations from above the Earth’s atmosphere. The atomic data that have become available since Moore’s compilations are referred to here as second-generation spectra.

You do not have subscription access to this journal. Citation lists with outbound citation links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

You do not have subscription access to this journal. Article tables are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

You do not have subscription access to this journal. Article level metrics are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Comparison between Present Knowledge and Information in the Astronomical Multiplet Tables for the First Spectra of Iron-Group Elements, Scandium to Nickel^{a}

Abbreviations: SE, singly excited configurations, 3d^{k}nl; DE, doubly excited configurations, 3d^{k}^{−1}4snl.
Abbreviations for the wavelength regions: UV1, <1 000 Å; UV2, 1 000–2 000 Å; UV3, 2 000–3 000 Å; opt1, 3 000–5 000 Å; opt2, 5 000–7 000 Å; opt3, 7 000-10 000 Å; IR, 10 000Å;.
Key to the grading: Å;, Transition array(s) complete or nearly complete; B, supermultiplets known for more than the lowest subconfigurations; C, supermultiplets between lowest subconfigurations complete or nearly complete; D, analysis fragmentary, only a few lines known; —, no transitions known.
3d^{2}(^{M}L)nl has five subconfigurations, based on five parent terms; 3d(^{2}D)4snl has one subconfiguration, based on the ^{2}D grandparent term.
The thesis of Forsberg11 contains 439 levels, which form the basis for the survey here. AEL-S includes 379 Ti i levels. 3d^{3}(^{M}L)nl has 8 subconfigurations, based on 8 parent terms; 3d^{2}(^{M}L)4snl has 5 subconfigurations, based on 5 grandparent terms.
3d^{4}(^{M}L)nl has 16 subconfigurations, based on 16 parent terms; 3d^{3}(^{M}L)4snl has 8 subconfigurations, based on 8 grandparent terms.
3d^{5}(^{M}L)nl has 16 subconfigurations, based on 16 parent terms; 3d^{4}(^{M}L)4snl has 16 subconfigurations, based on 16 grandparent terms.
3d^{6}(^{M}L)nl has 16 subconfigurations, based on 16 parent terms; 3d^{5}(^{M}L)4snl has 16 subconfigurations, based on 16 grandparent terms.
3d^{7}(^{M}L)nl has 8 subconfigurations, based on 8 parent terms; 3d^{6}(^{M}L)4snl has 16 subconfigurations, based on 16 grandparent terms.
3d^{8}(^{M}L)nl has 5 subconfigurations, based on 5 parent terms; 3d^{7}(^{M}L)4snl has 8 subconfigurations, based on 8 grandparent terms.
3d^{9}(^{2}D)nl has 1 subconfiguration, based on the ^{2}D parent term; 3d^{8}(^{M}L)4snl has 5 subconfigurations, based on 5 grandparent terms.

Table 2

Comparison between Present Knowledge and Information in the Astronomical Multiplet Tables for the Second Spectra of Iron-Group Elements, Scandium to Nickel^{a}

See Table 1 and the text for an explanation of the construction of the table.
Each configuration has only one subconfiguration, which means that grades B and C are irrelevant.
3d^{2}(^{M}L)nl has 5 subconfigurations, based on 5 parent terms; 3d(^{2}D)4snl has 1 subconfiguration, based on the ^{2}D grandparent term.
3d^{3}(^{M}L)nl has 8 subconfigurations, based on 8 parent terms; 3d^{2}(^{M}L)4snl has 5 subconfigurations, based on 5 grandparent terms.
3d^{4}(^{M}L)nl has 16 subconfigurations, based on 16 parent terms; 3d^{3}(^{M}L)4snl has 8 subconfigurations, based on 8 grandparent terms.
3d^{5}(^{M}L)nl has 16 subconfigurations, based on 16 parent terms; 3d^{4}(^{M}L)4snl has 16 subconfigurations, based on 16 grandparent terms.
3d^{6}(^{M}L)nl has 16 subconfigurations, based on 16 parent terms; 3d^{5}(^{M}L)4snl has 16 subconfigurations, based on 16 grandparent terms.
3d^{7}(^{M}L)nl has 8 subconfigurations, based on 8 parent terms; 3d^{6}(^{M}L)4snl has 16 subconfigurations, based on 16 grandparent terms.
3d^{8}(^{M}L)nl has 5 subconfigurations, based on 5 parent terms; 3d^{7}(^{M}L)4snl has 8 subconfigurations, based on 8 grandparent terms.

Table 3

Comparison between Present Knowledge and Information in the Astronomical Multiplet Tables for the Third Spectra of Iron-Group Elements, Scandium to Nickel^{a}

For an explanation of the construction of the table, see Table 1 and text.
Sc iii is an alkalilike spectrum because of one electron outside a closed 3p shell.
Each configuration has only one subconfiguration, which means that grades B and C are irrelevant.
3d^{2}(^{M}L)nl has 5 subconfigurations, based on 5 parent terms; 3d(^{2}D)4snl has 1 subconfiguration, based on the ^{2}D grandparent term.
3d^{3}(^{M}L)nl has 8 subconfigurations, based on 8 parent terms; 3d^{2}(^{M}L)4snl has 5 subconfigurations, based on 5 grandparent terms.
3d^{4}(^{M}L)nl has 16 subconfigurations, based on 16 parent terms; 3d^{3}(^{M}L)4snl has 8 subconfigurations, based on 8 grandparent terms.
3d^{5}(^{M}L)nl has 16 subconfigurations, based on 16 parent terms; 3d^{4}(^{M}L)4snl has 16 subconfigurations, based on 16 grandparent terms.
3d^{6}(^{M}L)nl has 16 subconfigurations, based on 16 parent terms; 3d^{5}(^{M}L)4snl has 16 subconfigurations, based on 16 grandparent terms.
3d^{7}(^{M}L)nl has 8 subconfigurations, based on 8 parent terms; 3d^{6}(^{M}L)4snl has 16 subconfigurations, based on 16 grandparent terms.

Tables (3)

Table 1

Comparison between Present Knowledge and Information in the Astronomical Multiplet Tables for the First Spectra of Iron-Group Elements, Scandium to Nickel^{a}

Abbreviations: SE, singly excited configurations, 3d^{k}nl; DE, doubly excited configurations, 3d^{k}^{−1}4snl.
Abbreviations for the wavelength regions: UV1, <1 000 Å; UV2, 1 000–2 000 Å; UV3, 2 000–3 000 Å; opt1, 3 000–5 000 Å; opt2, 5 000–7 000 Å; opt3, 7 000-10 000 Å; IR, 10 000Å;.
Key to the grading: Å;, Transition array(s) complete or nearly complete; B, supermultiplets known for more than the lowest subconfigurations; C, supermultiplets between lowest subconfigurations complete or nearly complete; D, analysis fragmentary, only a few lines known; —, no transitions known.
3d^{2}(^{M}L)nl has five subconfigurations, based on five parent terms; 3d(^{2}D)4snl has one subconfiguration, based on the ^{2}D grandparent term.
The thesis of Forsberg11 contains 439 levels, which form the basis for the survey here. AEL-S includes 379 Ti i levels. 3d^{3}(^{M}L)nl has 8 subconfigurations, based on 8 parent terms; 3d^{2}(^{M}L)4snl has 5 subconfigurations, based on 5 grandparent terms.
3d^{4}(^{M}L)nl has 16 subconfigurations, based on 16 parent terms; 3d^{3}(^{M}L)4snl has 8 subconfigurations, based on 8 grandparent terms.
3d^{5}(^{M}L)nl has 16 subconfigurations, based on 16 parent terms; 3d^{4}(^{M}L)4snl has 16 subconfigurations, based on 16 grandparent terms.
3d^{6}(^{M}L)nl has 16 subconfigurations, based on 16 parent terms; 3d^{5}(^{M}L)4snl has 16 subconfigurations, based on 16 grandparent terms.
3d^{7}(^{M}L)nl has 8 subconfigurations, based on 8 parent terms; 3d^{6}(^{M}L)4snl has 16 subconfigurations, based on 16 grandparent terms.
3d^{8}(^{M}L)nl has 5 subconfigurations, based on 5 parent terms; 3d^{7}(^{M}L)4snl has 8 subconfigurations, based on 8 grandparent terms.
3d^{9}(^{2}D)nl has 1 subconfiguration, based on the ^{2}D parent term; 3d^{8}(^{M}L)4snl has 5 subconfigurations, based on 5 grandparent terms.

Table 2

Comparison between Present Knowledge and Information in the Astronomical Multiplet Tables for the Second Spectra of Iron-Group Elements, Scandium to Nickel^{a}

See Table 1 and the text for an explanation of the construction of the table.
Each configuration has only one subconfiguration, which means that grades B and C are irrelevant.
3d^{2}(^{M}L)nl has 5 subconfigurations, based on 5 parent terms; 3d(^{2}D)4snl has 1 subconfiguration, based on the ^{2}D grandparent term.
3d^{3}(^{M}L)nl has 8 subconfigurations, based on 8 parent terms; 3d^{2}(^{M}L)4snl has 5 subconfigurations, based on 5 grandparent terms.
3d^{4}(^{M}L)nl has 16 subconfigurations, based on 16 parent terms; 3d^{3}(^{M}L)4snl has 8 subconfigurations, based on 8 grandparent terms.
3d^{5}(^{M}L)nl has 16 subconfigurations, based on 16 parent terms; 3d^{4}(^{M}L)4snl has 16 subconfigurations, based on 16 grandparent terms.
3d^{6}(^{M}L)nl has 16 subconfigurations, based on 16 parent terms; 3d^{5}(^{M}L)4snl has 16 subconfigurations, based on 16 grandparent terms.
3d^{7}(^{M}L)nl has 8 subconfigurations, based on 8 parent terms; 3d^{6}(^{M}L)4snl has 16 subconfigurations, based on 16 grandparent terms.
3d^{8}(^{M}L)nl has 5 subconfigurations, based on 5 parent terms; 3d^{7}(^{M}L)4snl has 8 subconfigurations, based on 8 grandparent terms.

Table 3

Comparison between Present Knowledge and Information in the Astronomical Multiplet Tables for the Third Spectra of Iron-Group Elements, Scandium to Nickel^{a}

For an explanation of the construction of the table, see Table 1 and text.
Sc iii is an alkalilike spectrum because of one electron outside a closed 3p shell.
Each configuration has only one subconfiguration, which means that grades B and C are irrelevant.
3d^{2}(^{M}L)nl has 5 subconfigurations, based on 5 parent terms; 3d(^{2}D)4snl has 1 subconfiguration, based on the ^{2}D grandparent term.
3d^{3}(^{M}L)nl has 8 subconfigurations, based on 8 parent terms; 3d^{2}(^{M}L)4snl has 5 subconfigurations, based on 5 grandparent terms.
3d^{4}(^{M}L)nl has 16 subconfigurations, based on 16 parent terms; 3d^{3}(^{M}L)4snl has 8 subconfigurations, based on 8 grandparent terms.
3d^{5}(^{M}L)nl has 16 subconfigurations, based on 16 parent terms; 3d^{4}(^{M}L)4snl has 16 subconfigurations, based on 16 grandparent terms.
3d^{6}(^{M}L)nl has 16 subconfigurations, based on 16 parent terms; 3d^{5}(^{M}L)4snl has 16 subconfigurations, based on 16 grandparent terms.
3d^{7}(^{M}L)nl has 8 subconfigurations, based on 8 parent terms; 3d^{6}(^{M}L)4snl has 16 subconfigurations, based on 16 grandparent terms.