Part 1 — TABLE XI
Reading edition
Series Wave-Lenght Int. Cl. Attribution Int. Wave-Lenght
3613.84 60 II -, Sc 4 3613.947
3645.31 30 III Sc?, - 3 3645.475
3630.76 50 II 4 3630.876
3666.54 3 III 1 3666.676
3651.81 25 III -, Sc 4 3651.940
3642.79 40 II Sc 2 3642.912
3572.53 50 II -, Sc 6 3572.71
3558.55 20 II (Fe 8 3558.672)
3590.48 20 II 2 3590.609
3576.35 35 II -, Sc? 3 3576.527
3567.70 20 II 4 3567.835
3589.64 20 II 5 3589.773
3580.94 30 II 5 3581.067
5657.89 25 V E Y, - 2 5658.09
5684.21 12 V E 1 5684.415
5640.99 15 V E 2 5641.206
5667.16 9 V E 0 5667.368
5658.35 8 V E 0 5658.561
5669.05 10 V E 1 5669.258
4374.46 40 III E Sc, Fe? 3 3374.628
4420.66 2 00 4420.832
4354.60 5 V E 1 4354.776
4400.38 30 III E Sc 3 4400.555
4431.35 3 V E 0 4431.525
4384.80 6 IV E 0 4384.986
4415.55 20 III E 2 4415.722
4314.09 60 III E Sc 3 4314.248
4294.77 8 IV E Zr 2 4294.932
4320.73 50 III E Sc 3 4320.90
4279.95 1 - - ----
4305.70 10 IV E 2 4305.871
4325.00 40 III E Sc 4 4325.152
From an examination of Rowland’s tables of the solar spectrum, it appears that the fainter components of the multiplets invariably accompany the stronger ones, thus making the identifications certain. Only the stronger components are, however, powerful enough to appear in stellar spectra, with the dispersions ordinarily used.
The following multiplets, as analyzed by Russell[290] and Kiess,[291] are definitely present: , , , , , , , , , , . Doubtfully present are: , .
The maximum of these lines is difficult to determine; they are not well placed for measurement, many of the most important are seriously blended, and all are rather faint, even at maximum. They are first seen[292] at Class , and their maximum appears to be[293] at or .
The solar intensities of the lines of both neutral and ionized titanium fall off regularly with increasing excitation potential. The subject is discussed in Chapter VII, as part of the evidence for the validity of the Saha theory.[294]
IONIZED TITANIUM
The lines of ionized titanium are about as strong in the solar spectrum as those of the neutral atom. Many of them appear, with the lines of the ionized iron atom, with abnormal strength in the spectra of the c-stars.[295] The following multiplets[296] are present in the solar spectrum: , , , , , , , , , , , , , , , , , , , , , . Doubtfully present are , , , . The lines which are especially enhanced in the c-stars are: , , , , , , , .
The lines of ionized titanium come to a maximum at about Class , but a significant maximum is difficult to determine, for the lines are extremely sensitive to absolute magnitude. Menzel,[297] using Cassiopeiae (classed by him as ) for his typical star, found a maximum development of lines in that star. The present writer,[298] using the wider selection of stars enumerated in the appendix, obtains as the maximum for Ti+. A glance at the measures[299] will indicate that the position of the maximum is in any case very uncertain, as the intensity does not change smoothly in going from class to class.
COMPOUNDS OF TITANIUM
The absorption bands of titanium oxide, TiO₂, are the characteristic flutings[300][301] of the stars of Class , and the strength of these bands has been proposed[302] as a criterion of class for the stars in which they are found. It is perhaps noteworthy that titanium, zirconium, and carbon, the only elements which give oxides in stellar spectra (hydrogen excepted) belong to the fourth group of the periodic system.
VANADIUM (23)
The vanadium lines are best identified by intensity from Rowland’s table. The following multiplets[303] are present in the solar spectrum: , , , , , , . The multiplet is well seen in stellar spectra from onwards, and increases in strength as cooler stars are approached.[304] Slipher[305] called attention to the strength in Ceti of the vanadium group near 4400, presumably the two multiplets , , with excitation potential 0.28 volts.
IONIZED VANADIUM
Three multiplets, all far in the ultra-violet, are tabulated for ionized vanadium by Meggers, Kiess, and Walters,[306] and two of them are within the range of Rowland’s table. All the lines of these, the and multiplets, have been satisfactorily identified with solar lines. The strength of the ultimate lines of ionized vanadium, which occur in the multiplet last named, is a little greater, in the solar spectrum, than that of the strongest lines of the neutral atom, at 4379, which are also ultimate lines.
The following tabulation contains, in the same form as Table XI, the data respecting the two multiplets which are identified in the solar spectrum.