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. [Pg 74] 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 [Pg 75] 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