The Intensities of Lines in Multiplets II. Observed Data

PHYSICS: H. N. RUSSELL

322

PROC. N. A. S.

number zero (in the common notation) and excluded by Lande's rule. This rule appears therefore to be a consequence of the combination principle, as Burger and Honl have already shown in the analogous case of the Zeeman patterns. A further test of the formula, and a severe one, -is found in the symmetrical multiplets for which R > K. In the DD' group of the sextet system, the next line to the end is very faint, and in the corresponding septet group it is absent. Both phenomena are predicted by the present theory. 6

1 The references will be found all together at the end of the second paper on p. 328.

THE INTENSITIES OFLINESIN MULTIPLETS. DA TA By HZNRY NoRRis RUSSZLL

I.

OBSERVED

MOUNT WILSON OBSZRVATORY, CARNZGI8 INSTITUTION OP WASHINGTON

Communicated May 8, 1925

The theory developed in the preceding paper is here compared with the observed data. (a) Precise Measures.-Very few precise measures of intensity have yet been published for multiplets of the triplet and higher systems-which alone are of importance to test the theory, as the sum-rule suffices for the doublets. To save space they are printed below with the x's, y's and z's in the same line, separated by semi-colons, rather than in the ordinary multiplet arrangement. In the symmetrical groups, the means of the observed values have been taken for the lines which should theoretically be equal (the observed differences being within the observational errors). The computed values are adjusted so that their sum equals that of the observed intensities for the whole multiplet. PD

DF

DD'

obs. 100, comp. 101,

Triplet System" 18; 25; 19,

54.5

24

18

18