FOOTNOTES:
[370] Proc. Roy. Soc., 99A, 136, 1921.
[371] M. N. R. A. S., 83, 403, 1923; ibid., 84, 499, 1924.
[372] M. N. R. A. S., 83, 403, 1923.
[373] M. N. R. A. S., 84, 499, 1924.
[374] R. H. Fowler, Phil. Mag., 45, 1, 1923.
[375] Bohr, Mem. Ac. Roy. Den., 4, 2, 76, 1922.
[376] Ap. J., 59, 1, 1924.
[378] Proc. Roy. Soc., 103A, 413, 1923.
[379] M. N. R. A. S., 83, 404, 1923.
[380] H. C. 258, 1924.
[381] H. C. 252, 256, 1924.
[382] Phil. Mag., 47, 209, 1924.
[384] Proc. Phys. Soc. Lond., 36, 94, 924.
[386] Ap. J., 59, 197, 1924.
[387] See, for instance, H. J. H. Fenton, Outlines of Chemistry, 128, 1918.
[388] Lindemann, quoted by Milne, Observatory, 44, 264, 1921.
[389] Milne, Observatory, 44, 264, 1921.
[391] C. R., 171, 1106, 1920.
[392] Russell, Ap. J., in press.
[393] A. S. King, Mt. W. Contr. 247, 1922.
[394] A. S. King, Mt. W. Contr. 233, 1922.
[395] Ap. J., 57, 20, 1923.
[396] Mt. W. Contr. 225, 1922.
[397] Mt. W. Contr. 236, 1922.
[398] Saha and Swe, Nature, 115, 377, 1925.
[399] Nature, 115, 534, 1925.
[400] Phys. Zeit., 18, 121, 1917.
[401] Phil. Mag., 47, 209, 1924.
[402] Payne, Proc. N. Ac. Sci., 11, 197, 1925.
CHAPTER VIII
OBSERVATIONAL MATERIAL FOR THE TEST OF IONIZATION THEORY
THE observational test of ionization theory involves a considerable program of measurement, if the accuracy necessary for a quantitative test is to be attained. The present chapter contains a synopsis of new data obtained by the writer to supplement the material already published in Harvard Circulars.[403][404] The data here presented practically complete the available material for the strong lines of known series relations in the region of the spectrum usually examined.
LINE INTENSITY
The theory predicts the degree of absorption that will be produced by each atom at a given temperature, and the related quantity that is measured is the intensity of the corresponding Fraunhofer line in the spectrum of the star. Spectrum lines are differentiated by various qualities, such as width, darkness, and wings, and their conspicuousness is governed by the intensity of the neighboring continuous background. It is not easy to specify all these quantities on an intensity scale that is one-dimensional, and the various ways in which line intensities have been estimated represent different attempts to choose and express a suitable scale.
Many of the applications of so-called line-intensity, such as the estimation of spectroscopic parallaxes, have involved ratios between the strengths of various lines in the same spectrum. This method of comparison avoids most of the difficulties caused by differences of line character and continuous background, for the lines that are to be compared are chosen because of their proximity and comparability. Harper and Young[405] have standardized the method by comparing spectrum line ratios with line ratios on an artificial scale.
METHOD OF ESTIMATING INTENSITY
In a comparison of ionization theory with observation, some measure of line-intensity is required which can be compared from class to class. It seems probable that direct estimates of intensity, for spectra of the same dispersion, density, and definition, will be comparable within the limits of accuracy of the material.
Two series of spectra were measured by the writer in order to obtain material for the test of the theory of ionization. For the first group standard lines in the spectrum of
Cygni were used for the formation of a direct intensity scale, and for the second group, comprising the cooler stars, a strip of the solar spectrum was similarly employed. An arbitrary scale was constructed by assigning a series of intensities to well placed lines in the spectrum, and using these as standards. A list of the lines used for the second group, the assigned intensity, and the intensity as given in Rowland’s table, are contained in the following table.
| Line | Intensity | Line | Intensity | |||
|---|---|---|---|---|---|---|
| Assigned | Rowland | Assigned | Rowland | |||
| 4034 | 6 | 7 | 4046 | 10 | 30 | |
| 4035 | 5 | 6 | 3968 | 13 | 700 | |
| 4038 | 4 | 4 | 3934 | 15 | 1000 | |
| 4064 | 8 | 20 | ||||
The estimates thus made might be defined as estimates of width-intensity-contrast between the line and the continuous background. On an ideal plate which was not burned out, such estimates would give a measure of the total energy of the line relative to the neighboring continuous spectrum. The accuracy attained by direct estimates of this kind appears to be as great as the material warrants.
ACCURACY OF THE ESTIMATES
It is not possible at present to evaluate the accuracy of these estimates with the same precision as for other physical quantities, but the consistency of the readings from comparable plates of the same star will at least give a measure of the value of the estimates. [Table XVIII] contains the measures on forty-three lines in the spectrum of
Gruis, taken from six plates of the same dispersion, and comparable quality, density, and definition. Successive columns give the wave-length, the arithmetic mean intensity, and the standard deviation
.
[TABLEXVIII]
| Line | Int. | Line | Int. | Line | Int. | Line | Int. | ||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| 4215 | 8.4 | 1.0 | 4319 | 4.8 | 0.8 | 4376 | 7.8 | 0.6 | 4451 | 4.5 | 1.5 |
| 4227 | 16.0 | 1.4 | 4321 | 4.0 | 0.0 | 4379 | 4.2 | 0.3 | 4455 | 5.0 | 1.0 |
| 4247 | 6.0 | 0.0 | 4326 | 10.4 | 0.5 | 4383 | 10.3 | 0.8 | 4462 | 6.0 | 0.8 |
| 4250 | 7.0 | 0.0 | 4330 | 4.6 | 0.8 | 4395 | 6.3 | 0.4 | 4482 | 7.7 | 0.7 |
| 4254 | 9.0 | 1.0 | 4332 | 3.6 | 0.5 | 4398 | 2.7 | 0.8 | 4490 | 7.3 | 0.4 |
| 4260 | 9.0 | 2.1 | 4333 | 4.0 | 0.0 | 4402 | 6.3 | 0.4 | 4495 | 7.5 | 0.4 |
| 4272 | 8.7 | 0.8 | 4337 | 8.7 | 0.8 | 4405 | 9.0 | 0.5 | 4502 | 6.0 | 0.0 |
| 4275 | 9.5 | 1.3 | 4340 | 9.5 | 1.1 | 4409 | 9.0 | 0.5 | 4554 | 5.3 | 0.4 |
| 4283 | 4.3 | 0.4 | 4352 | 9.2 | 1.1 | 4415 | 7.7 | 0.8 | 4564 | 5.8 | 0.7 |
| 4290 | 10.6 | 1.0 | 4360 | 6.8 | 1.0 | 4435 | 9.2 | 0.9 | 4572 | 6.0 | 1.0 |
| 4315 | 8.3 | 0.7 | 4370 | 6.8 | 0.6 | 4444 | 8.9 | 1.2 |
These measures are strictly representative of the material as a whole, for the plates of
Gruis were measured at wide intervals in the ordinary course of the work, and were selected for illustration because there was a greater number of suitable plates of this star than for any other.
HOMOGENEITY OF MATERIAL
The observational material on line-intensities follows in tabular form. The measures were made in two groups, comprising respectively the hotter stars and the stars cooler than Class
, and different intensity scales were used for the two. The solar scale mentioned above was used for the second group of stars; the first group was referred to standard lines in the spectrum of
Cygni. The distribution of the stars in the two groups among the spectral classes was as follows:
| Group I | ||||||||
|---|---|---|---|---|---|---|---|---|
| giants | 4 | 7 | 7 | 6 | 8 | 6 | 3 | 17 |
| super-giants | - | - | - | - | 2 | 1 | - | - |
| Group II | |||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| dwarfs | - | - | - | - | - | 4 | 1 | 2 | 3 | 2 | 2 | - | - | - | - | - | - |
| giants | 1 | 9 | 3 | 5 | 2 | - | - | - | - | 3 | 5 | 20 | 4 | 8 | 1 | 5 | 1 |
| super-giants | - | - | - | - | - | 3 | 1 | 5 | 1 | 2 | - | 2? | 1? | 1? | 3 | 1 | - |
If it were possible to use a series of giants throughout, the task of determining the intensity maxima would be greatly simplified. Among the hotter stars the differences introduced by absolute magnitude are not great enough to make the maxima difficult to determine. With later classes, however, the changes with absolute magnitude are very marked. As will be pointed out in an ensuing chapter,[406] the actual strength of the lines differs considerably from giant to dwarf, owing to the difference in the effective optical depth of the photosphere. This difference in strength is in addition to the well-known “absolute magnitude effect” which is shown, for example, by the enhanced lines; it increases the difficulty of making estimates of line change from one class to the next, since, owing to selection, the available stars are far from homogeneous in absolute magnitude. In addition to this factor, there is the practical difficulty of making comparable estimates on the sharp narrow lines of a super-giant and those of a dwarf, since the lines of a dwarf tend to be hazy and lack contrast with the background.
It might be expected, from the distribution in luminosity of the stars used, that irregularities in the intensity sequence would probably occur in the
classes and at
. For the purpose of estimation of maxima, the
classes are not of very great importance, as few of the maxima under present investigation occur there, but the irregularity at
may well prove to be serious. There is indeed a general tendency for the intensity of, metallic lines to increase at
. All the
stars measured were of very high luminosity, and probably the rise of intensity is due to this feature, or rather to the increase of material above the photosphere that accompanies it. A maximum is only assumed to occur at
when a line increases regularly through the
types, as do the lines of neutral calcium. The iron and titanium maxima obviously occur earlier in the sequence, although the lines of both these elements are often noticeably strengthened at
.
The following tabulation contains the data on line-intensity for all the lines of known series relations that have been measured up to the present. All the measures were made by the writer, excepting those for zinc, which are taken from Menzel’s paper.[407] Successive columns of the table contain the atom, the series relations, the wave-length, and the observed intensities in the various spectral classes. The column headed “Blends” is a direct transcription from Rowland’s tables, and contains details both of the line under consideration and of closely adjacent lines. The column headed “Remarks” contains the writer’s own conclusions, based on solar evidence, astrophysical behavior, and laboratory affinities, as to the source and maximum of the line that has been measured.
The recorded intensities, for classes cooler than
, are derived from the selection of stars mentioned earlier in the present chapter. A list of the individual stars is contained in [Appendix III]. Four typical
stars have been selected to represent that class. The figures in the final column refer to the notes to the table, which are listed under the respective atoms, and give the observed maximum, the intensities and origins of blended lines (in Rowland’s notation), and short remarks, which indicate whether or no the observed behavior is to be attributed to the line considered. Maxima that are obviously due to another line are placed in parentheses.
[TABLE XIX]
| Atom | Series | Notes | ||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| H | 3970.1 | 20.0 | 17.6 | 20.0 | 15.6 | 15.0 | 17.2 | 17.8 | .. | 18.0 | 20.0 | 24.5 | .. | .. | 30.0 | .. | [1] | |
| 4101.7 | 18.0 | 16.0 | 16.3 | 13.6 | 15.0 | 13.9 | 10.7 | 10.6 | 9.4 | 7.0 | 7.0 | 7.0 | 7.3 | 9.0 | 6.0 | [2] | ||
| 4340.5 | .. | 16.0 | 14.3 | 12.2 | 14.6 | 13.2 | 10.8 | 9.2 | 9.4 | 9.0 | 8.7 | 8.4 | 9.2 | 9.6 | 9.0 | [3] | ||
| 4861.3 | 15.0 | 14.0 | 14.0 | 14.6 | 13.3 | 12.3 | 11.0 | 9.0 | 8.5 | 7.6 | 6.6 | 5.6 | 5.1 | 6.7 | 4.0 | [4] | ||
| He | 4713.4 | .. | .. | .. | .. | 6.5 | 8.2 | 7.5 | 6.0 | 6.7 | 4.2 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | [1] | |
| 4713.1 | ||||||||||||||||||
| 4121.0 | .. | .. | .. | .. | 8.5 | 9.5 | 11.0 | 9.2 | 6.4 | 4.2 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | [2] | ||
| 4120.9 | ||||||||||||||||||
| 4471.7 | .. | 6.5 | 8.5 | 8.0 | 11.0 | 11.5 | 11.6 | 11.8 | 11.1 | 9.7 | 8.0 | 0.0 | 0.0 | 0.0 | 0.0 | [3] | ||
| 4471.5 | ||||||||||||||||||
| 4026.4 | 4.0 | 6.9 | 9.0 | 8.0 | 12.0 | 12.7 | 14.0 | 15.4 | 12.0 | 10.8 | 8.5 | 0.0 | 0.0 | 0.0 | 0.0 | [4] | ||
| 4026.2 | ||||||||||||||||||
| 4921.9 | .. | .. | .. | .. | 10.0 | 12.4 | 10.7 | 10.0 | 10.0 | 7.0 | 4.0 | 0.0 | 0.0 | 0.0 | 0.0 | [5] | ||
| 4387.9 | .. | .. | 4.0 | 4.0 | 10.0 | 10.3 | 11.0 | 11.5 | 9.2 | .. | 4.0 | 0.0 | 0.0 | 0.0 | 0.0 | [6] | ||
| 4143.8 | .. | .. | 5.0 | 4.0 | 9.6 | 10.0 | 10.7 | 12.0 | 7.5 | 4.9 | 3.5 | 0.0 | 0.0 | 0.0 | 0.0 | [7] | ||
| 4009.3 | .. | .. | .. | .. | 7.0 | 9.1 | 10.2 | 11.4 | 5.8 | 4.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | [8] | ||
| He+ | 4685.8 | em. | 5.8 | em. | 6.0 | 4.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | [9] | |
| 4541.6 | 6.0 | 5.3 | 5.5 | 6.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | [10] | ||
| 4199.9 | 5.0 | 3.5 | 6.1 | 5.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | [11] | ||
| 4025.6 | 4.0 | 6.9 | 9.0 | 8.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | [12] | ||
| C+ | 4267 | 0.0 | 0.0 | 0.0 | 0.0 | 5.0 | 7.4 | 7.7 | 8.0 | 7.8 | 4.5 | 3.0 | 0.0 | 0.0 | 0.0 | 0.0 | [1] | |
| Mg | 5183.7 | |||||||||||||||||
| 5172.7 | .. | .. | .. | .. | .. | 8.0 | .. | .. | 8.0 | 8.0 | 8.0 | 10.0 | 8.0 | 10.0 | .. | [1] | ||
| 5167.4 | ||||||||||||||||||
| 4571.1 | .. | .. | .. | .. | 2.0 | 3.5 | 5.2 | 3.3 | 6.4 | 5.8 | 6.2 | 6.8 | 6.9 | 7.0 | 6.1 | [2] | ||
| 4351.9 | .. | 2.0 | 4.0 | 5.0 | 4.3 | 6.3 | 7.4 | 5.0 | 7.3 | 8.1 | 8.0 | 7.0 | 8.1 | 8.6 | 9.0 | [3] | ||
| Mg+ | 4481.3 | 5.0 | 4.6 | 6.0 | 5.5 | 6.7 | 8.0 | 7.2 | 8.1 | 8.3 | 8.6 | 9.0 | 7.7 | 8.0 | 9.4 | 7.6 | [4] | |
| 4481.1 | ||||||||||||||||||
| Al | 3961.3 | .. | tr. | 2.0 | 5.3 | .. | 5.7 | 5.5 | .. | 8.3 | 8.0 | 8.5 | .. | .. | 9.0 | 11.0 | [1] | |
| 3944.0 | .. | tr. | 2.0 | 6.0 | .. | 5.2 | 6.0 | 8.0 | 8.0 | 8.3 | 8.5 | .. | .. | 8.5 | 11.0 | [2] | ||
| Si | 3905 | .. | .. | 2.0 | .. | 4.0 | 8.8 | 9.3 | 11.5 | 11.7 | 11.4 | 11.3 | 10.0 | 10.0 | 9.6 | 8.6 | [1] | |
| Si+ | 4131 | .. | .. | .. | .. | 2.0 | 3.0 | 2.7 | 3.5 | 4.4 | 3.6 | 6.2 | 9.3 | 7.0 | .. | .. | [2] | |
| 4128 | .. | .. | .. | .. | 2.0 | 3.0 | 2.7 | 3.5 | 4.4 | 3.6 | 6.2 | 9.3 | 7.0 | .. | .. | |||
| Si++ | 4574 | 0.0 | 0.0 | 0.0 | 0.0 | 3.0 | 8.0 | 8.0 | 2.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | [3] | |
| 4568 | 0.0 | 0.0 | 0.0 | 0.0 | 2.0 | 9.0 | 9.0 | 4.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | [4] | ||
| 4552 | 0.0 | 0.0 | 0.0 | 0.0 | 5.0 | 10.0 | 10.0 | 5.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | [5] | ||
| Si+++ | 4116 | .. | .. | 5.0 | 6.0 | 8.3 | 4.7 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | [6] | |
| 4096 | .. | .. | 8.7 | 6.0 | 9.7 | 5.2 | 3.6 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | [7] | ||
| 4089 | .. | .. | 7.5 | 8.0 | 9.2 | 5.5 | 5.2 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | [8] | ||
| Ca | 4581.4 | 0.0 | 0.0 | 0.0 | 3.0 | 2.5 | 4.2 | 6.7 | 5.0 | 7.7 | 8.1 | 7.8 | 8.0 | 7.1 | 8.3 | 6.2 | [1] | |
| 4454.8 | 0.0 | 0.0 | 0.0 | 3.0 | 5.0 | 2.6 | 5.0 | 6.2 | 6.0 | 5.1 | 5.0 | 4.8 | 4.4 | 5.6 | 5.0 | [2] | ||
| 4434.9 | 0.0 | 0.0 | 0.0 | 4.0 | 4.3 | 5.2 | 6.2 | 6.0 | 7.5 | 7.6 | 7.9 | 9.2 | 8.8 | 9.7 | 9.3 | [3] | ||
| 4307.7 | 0.0 | 3.3 | 3.0 | 4.4 | 3.6 | 4.9 | 6.5 | 7.2 | 9.5 | 8.6 | 8.6 | 10.3 | 10.5 | 12.0 | 13.1 | [4] | ||
| 4302.5 | 0.0 | 0.0 | 0.0 | .. | 8.0 | .. | 3.5 | .. | .. | 5.5 | .. | 4.0 | 4.5 | 5.0 | 8.0 | [5] | ||
| 4299.0 | 0.0 | 0.0 | 3.0 | 5.2 | 5.0 | 6.8 | 7.4 | 6.5 | 6.6 | 8.0 | 8.0 | 8.6 | 7.9 | .. | 6.0 | [6] | ||
| 4289.4 | 0.0 | 0.0 | 3.0 | 4.4 | 4.6 | 7.6 | 7.8 | 6.7 | 8.2 | 7.4 | 7.7 | 8.6 | 9.3 | 11.4 | 10.5 | [7] | ||
| 4283.0 | 0.0 | 0.0 | 0.0 | .. | 5.0 | 3.0 | .. | .. | 4.0 | 5.0 | 6.1 | 5.0 | 6.0 | 8.0 | 4.4 | [8] | ||
| 4226.7 | 3.0 | 2.3 | 3.0 | 5.8 | 6.3 | 7.9 | 9.3 | 8.6 | 10.4 | 9.7 | 11.7 | 13.6 | 14.5 | 14.2 | 16.0 | [9] | ||
| Ca+ | 3968.5 | 20.0 | 17.6 | 20.0 | 15.6 | 15.0 | 17.2 | 17.8 | 20.0 | 18.0 | 20.0 | 24.5 | .. | .. | 30.0 | .. | [10] | |
| 3933.7 | 5.0 | 10.3 | 13.3 | 13.8 | 15.0 | 17.1 | 20.0 | 20.0 | 19.6 | 20.0 | 21.5 | .. | .. | 30.0 | .. | [11] | ||
| Sc+ | 4246.8 | 0.0 | 3.0 | 2.0 | 6.0 | 5.0 | 6.0 | 7.0 | 5.0 | 6.3 | 5.6 | 5.3 | 5.6 | 5.4 | 8.6 | 6.8 | [1] | |
| 4320.8 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 3.8 | 5.5 | 4.0 | 4.0 | 3.5 | 3.8 | 4.5 | 4.0 | 5.0 | 4.0 | [2] | ||
| Ti | 4395.2 | 0.0 | 0.0 | 0.0 | 3.0 | .. | 6.7 | 7.2 | .. | 5.7 | 5.7 | 5.4 | 6.2 | 6.8 | 7.2 | 6.5 | [1] | |
| 4301.1 | 0.0 | 0.0 | 0.0 | 0.0 | 8.0 | .. | 3.5 | .. | .. | 5.5 | .. | 4.0 | 4.5 | 5.0 | 8.0 | [2] | ||
| 4300.9 | 0.0 | 3.0 | 3.0 | .. | .. | 6.0 | 7.6 | 7.0 | 5.0 | 6.5 | 5.0 | 8.0 | 5.6 | 10.3 | 13.0 | [3] | ||
| 4298.7 | 0.0 | 0.0 | 3.0 | 5.2 | 5.0 | 6.8 | 7.4 | 6.5 | 6.6 | 8.0 | 8.0 | 8.6 | 7.9 | .. | 6.0 | [4] | ||
| 4290.9 | 0.0 | 0.0 | 3.0 | 4.4 | 4.6 | 7.6 | 7.8 | 6.7 | 8.2 | 7.4 | 7.7 | 8.6 | 9.3 | 11.4 | 10.5 | [5] | ||
| 4289.1 | ||||||||||||||||||
| 4274.6 | 0.0 | 0.0 | 1.0 | 3.0 | 0.0 | 3.5 | 5.2 | 5.0 | 6.2 | 7.2 | 7.6 | 9.0 | 8.4 | 9.5 | 9.4 | [6] | ||
| 3998.7 | 0.0 | 0.0 | 1.5 | 4.5 | 6.0 | 5.6 | 7.0 | 6.0 | 7.0 | 7.0 | 6.5 | .. | 7.0 | 8.0 | .. | [7] | ||
| Ti+ | 4571.9 | 0.0 | 0.0 | 0.0 | 0.0 | 2.0 | 3.5 | 5.2 | 3.3 | 6.4 | 5.8 | 6.2 | 6.8 | 6.9 | 7.0 | 6.1 | [8] | |
| 4563.8 | 0.0 | 0.0 | 0.0 | 0.0 | 2.0 | 2.5 | 5.2 | 3.3 | 6.6 | 6.4 | 6.7 | 7.2 | 6.9 | 7.0 | 5.6 | [9] | ||
| 4501.3 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 4.0 | 6.6 | 5.3 | 6.8 | 6.0 | 6.4 | 6.8 | 7.0 | 6.6 | 6.0 | [10] | ||
| 4443.8 | 0.0 | 0.0 | 0.0 | 5.0 | 8.0 | 6.9 | 8.1 | 7.8 | 7.5 | 7.6 | 7.9 | 9.2 | 8.6 | 8.0 | 9.0 | [11] | ||
| 4395.0 | 0.0 | 0.0 | 0.0 | 3.0 | .. | 6.7 | 7.2 | .. | 5.7 | 5.7 | 5.4 | 6.2 | 6.8 | 6.0 | 6.5 | [12] | ||
| 4337.9 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 5.0 | 6.3 | 5.0 | 7.2 | 7.8 | 7.2 | 7.2 | 8.9 | 9.0 | 8.3 | [13] | ||
| 4315.0 | 0.0 | 3.0 | 3.5 | 5.0 | 4.6 | 6.9 | 7.5 | 4.6 | 6.6 | 5.6 | 6.1 | 7.0 | 7.0 | 8.0 | 8.1 | [14] | ||
| 4307.9 | 0.0 | 3.3 | 3.0 | 4.4 | 3.6 | 4.9 | 6.5 | 7.2 | 9.5 | 8.6 | 8.6 | 10.3 | 10.5 | 12.0 | 13.1 | [15] | ||
| 4301.9 | 0.0 | 0.0 | 0.0 | 0.0 | 8.0 | .. | 3.5 | .. | .. | 5.5 | .. | 4.0 | 4.5 | 5.0 | 8.0 | [16] | ||
| 4300.0 | 0.0 | 3.0 | 3.0 | .. | .. | 6.0 | 7.6 | 7.0 | 5.0 | 6.5 | 5.0 | 8.0 | 5.6 | 10.0 | 13.0 | [17] | ||
| 4290.2 | 0.0 | 0.0 | 3.0 | 4.4 | 4.6 | 7.6 | 7.8 | 6.7 | 8.2 | 7.4 | 7.7 | 8.6 | 9.3 | 11.0 | 10.5 | [18] | ||
| V | 4395.2 | 0.0 | 0.0 | 0.0 | 3.0 | 0.0 | 6.7 | 7.2 | .. | 5.7 | 5.7 | 5.4 | 6.2 | 6.8 | 7.2 | 6.5 | [1] | |
| 4379.2 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 3.0 | 2.5 | 3.0 | 3.7 | 2.5 | 2.8 | 3.5 | 3.0 | 4.0 | 4.2 | [2] | ||
| 4332.8 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 4.0 | .. | .. | 4.5 | 5.0 | 4.5 | 5.0 | 4.0 | 5.0 | 4.2 | [3] | ||
| 4330.1 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 4.5 | 5.0 | 4.5 | 4.5 | 4.0 | 3.5 | 3.8 | [4] | ||
| Cr | 4359.8 | 0.0 | 2.0 | .. | 3.0 | .. | 3.6 | 5.6 | 5.0 | 6.8 | 6.2 | 6.3 | 6.8 | 7.1 | 6.0 | 6.6 | [1] | |
| 4351.9 | 0.0 | 2.0 | 4.0 | 5.0 | 4.3 | 6.3 | 7.4 | 5.0 | 7.3 | 8.1 | 8.0 | 7.0 | 8.1 | 8.0 | 9.0 | [2] | ||
| 4289.7 | 0.0 | 0.0 | 3.0 | 4.4 | 4.6 | 7.6 | 7.8 | 6.7 | 8.2 | 7.4 | 7.7 | 8.6 | 9.3 | 11.4 | 10.5 | [3] | ||
| 4274.9 | 0.0 | 0.0 | 1.0 | 3.0 | .. | 3.5 | 5.2 | 5.0 | 6.2 | 7.2 | 7.6 | 9.0 | 8.4 | 9.5 | 9.4 | [4] | ||
| 4254.4 | 0.0 | 0.0 | 0.0 | 2.5 | 4.0 | 3.3 | 4.6 | 5.0 | 6.4 | 8.0 | 8.0 | 8.6 | 8.6 | 9.5 | 9.9 | [5] | ||
| Mn | 4451.6 | 0.0 | 2.0 | 3.0 | .. | 3.0 | 2.0 | .. | .. | 6.0 | 4.0 | 3.5 | 5.0 | .. | 5.0 | 5.0 | [1] | |
| 4414.9 | 3.0 | 2.3 | 3.3 | 4.8 | 4.6 | 6.4 | 8.0 | 7.2 | 7.0 | 6.5 | 7.2 | 7.6 | 7.4 | 7.0 | 8.0 | [2] | ||
| 4041.4 | 0.0 | 0.0 | 0.0 | 2.5 | 2.0 | 1.9 | 5.2 | 3.5 | 6.0 | 4.8 | 4.8 | 5.5 | 6.0 | 6.0 | 6.0 | [3] | ||
| 4036.5 | 0.0 | .. | .. | .. | .. | .. | .. | .. | .. | 3.3 | 4.0 | .. | .. | .. | .. | [4] | ||
| 4034.5 | 0.0 | .. | .. | .. | .. | .. | .. | .. | 5.0 | 3.6 | 4.0 | .. | 6.0 | .. | .. | [5] | ||
| 4033.1 | 0.0 | .. | .. | .. | .. | .. | 5.0 | 6.0 | 6.0 | 4.3 | 5.0 | .. | 7.0 | .. | .. | [6] | ||
| 4030.8 | 0.0 | 2.0 | 1.0 | 3.6 | 4.0 | 4.0 | 5.7 | 5.5 | 7.0 | 5.4 | 6.4 | 7.0 | 8.0 | 8.5 | 8.0 | [7] | ||
| 4068 | unclas. | .. | .. | .. | 4.3 | .. | 4.3 | 7.6 | 5.0 | 6.6 | 5.7 | 5.8 | 8.0 | 8.5 | 6.0 | 5.5 | [8] | |
| 4092 | unclas. | .. | .. | .. | 3.0 | .. | .. | .. | 3.0 | 4.0 | 4.2 | 4.2 | 5.0 | 5.0 | 6.0 | 5.5 | [9] | |
| Fe | 4489.7 | 0.0 | 0.0 | 2.0 | 0.0 | 0.0 | 4.2 | 7.2 | 6.3 | 6.8 | 6.8 | 7.6 | 8.4 | 7.4 | 8.0 | 7.6 | [1] | |
| 4482.3 | 0.0 | 4.0 | 4.6 | 6.0 | 5.5 | 6.7 | 8.0 | 7.2 | 8.1 | 8.3 | 8.6 | 9.0 | 7.7 | 8.0 | 7.6 | [2] | ||
| 4461.7 | 0.0 | 0.0 | 0.0 | 0.0 | 3.0 | 2.0 | 4.2 | 5.0 | 6.0 | 6.0 | 6.0 | 6.3 | 6.5 | 7.0 | 7.0 | [3] | ||
| 4375.9 | 0.0 | 0.0 | 2.5 | 4.4 | 5.5 | 6.7 | 7.1 | .. | 7.8 | 6.7 | 6.9 | .. | 8.0 | 7.0 | 8.8 | [4] | ||
| 4216.1 | 0.0 | 2.0 | 1.5 | 3.8 | 3.3 | 5.6 | 6.6 | 2.6 | 8.6 | 7.3 | 8.5 | 9.4 | 8.1 | 8.0 | 7.9 | [5] | ||
| 4415.1 | 3.0 | 2.3 | 3.3 | 4.8 | 4.6 | 6.4 | 8.0 | 7.2 | 7.0 | 6.5 | 7.2 | 7.6 | 7.4 | 7.0 | 8.0 | [6] | ||
| 4404.7 | 0.0 | 0.0 | 0.0 | 0.0 | 6.0 | 4.4 | 6.7 | 5.0 | 6.1 | 7.4 | 7.8 | 8.8 | 8.0 | 8.0 | 9.1 | [7] | ||
| 43834 | 3.0 | 2.5 | 4.0 | 5.4 | 4.6 | 6.7 | 7.0 | 8.2 | 9.1 | 10.3 | 10.3 | 10.5 | 9.9 | 11.0 | 10.3 | [8] | ||
| 4337.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 5.0 | 6.3 | 5.0 | 7.2 | 7.8 | 7.2 | 7.2 | 8.9 | 9.0 | 8.3 | [9] | ||
| 4291.4 | 0.0 | 0.0 | 3.0 | 4.4 | 4.6 | 7.6 | 7.8 | 6.7 | 8.2 | 7.4 | 7.7 | 8.6 | 9.3 | 11.0 | 10.5 | [10] | ||
| 4325.8 | 0.0 | 0.0 | 3.5 | 5.5 | 3.3 | 6.3 | 7.8 | 9.0 | 10.0 | 11.0 | 11.3 | 11.7 | 10.9 | 11.0 | 10.2 | [11] | ||
| 4307.9 | 0.0 | 3.3 | 3.0 | 4.0 | 3.6 | 4.9 | 6.5 | 7.2 | 9.5 | 8.6 | 8.6 | 10.3 | 10.5 | 12.0 | 13.1 | [12] | ||
| 4271.8 | 0.0 | 2.3 | 2.5 | 4.2 | 4.5 | 4.5 | 6.5 | 6.3 | 7.2 | 8.3 | 8.6 | 9.2 | 8.7 | 10.0 | 9.1 | [13] | ||
| 4260.5 | 0.0 | 3.0 | 1.5 | 4.2 | 4.0 | .. | 5.5 | 6.6 | 7.0 | 8.0 | 8.8 | 9.0 | 8.1 | 10.0 | 9.0 | [14] | ||
| 4290.8 | 0.0 | 0.0 | 2.0 | 3.6 | 4.0 | 5.6 | 5.3 | 6.3 | 6.4 | 7.8 | 7.9 | 8.4 | 8.0 | 9.0 | 7.6 | [15] | ||
| 4143.9 | 0.0 | 2.0 | 2.5 | 4.4 | 3.3 | 4.8 | 6.1 | 5.7 | 7.7 | 7.7 | 8.9 | 8.6 | 8.5 | 11.0 | 10.0 | [16] | ||
| 4132. | 0.0 | 3.6 | 2.0 | 4.0 | 2.0 | 4.2 | 6.0 | 4.0 | 6.0 | 5.2 | 5.5 | 6.0 | 6.5 | 5.0 | 4.0 | [17] | ||
| 4071.7 | 0.0 | 2.0 | 2.0 | 4.0 | 3.0 | 4.3 | 6.6 | 5.7 | 7.8 | 7.5 | 9.2 | 9.0 | 9.0 | 9.5 | 8.6 | [18] | ||
| 4063.6 | 0.0 | 2.0 | 2.0 | 3.6 | 4.0 | 4.8 | 5.8 | 5.6 | 7.2 | 7.5 | 8.0 | 9.0 | 8.0 | 9.5 | 9.0 | [19] | ||
| 4045.8 | 0.0 | 2.0 | 2.5 | 4.6 | 5.0 | 5.6 | 6.9 | 7.6 | 8.8 | 9.2 | 10.3 | 10.6 | 8.6 | 11.0 | 10.8 | [20] | ||
| 4005.2 | 0.0 | 0.0 | 2.5 | 4.6 | 5.5 | 5.0 | 6.3 | 6.0 | 8.3 | 7.2 | 6.6 | 9.0 | 8.0 | 7.0 | .. | [21] | ||
| 4299.2 | 0.0 | 3.0 | 3.0 | .. | .. | 6.0 | 7.6 | 7.0 | 5.0 | 6.5 | 5.0 | 8.0 | 5.6 | 10.3 | 13.0 | [22] | ||
| 4271.2 | 0.0 | 2.3 | 2.5 | 4.2 | 4.5 | 4.2 | 6.5 | 6.3 | 7.2 | 8.3 | 8.6 | 9.2 | 8.7 | 10.0 | 9.1 | [23] | ||
| 4260.5 | 0.0 | 3.0 | 1.5 | 4.2 | 4.0 | .. | 5.5 | 6.6 | 7.0 | 8.0 | 8.0 | 9.0 | 8.1 | 8.5 | 9.0 | [24] | ||
| 4250.1 | 0.0 | 0.0 | 2.0 | 3.6 | 4.0 | 5.6 | 5.3 | 6.3 | 6.4 | 7.8 | 7.9 | 8.4 | 8.0 | 9.0 | 7.6 | [25] | ||
| 4187.8 | 0.0 | 0.0 | 2.0 | 5.0 | 6.0 | .. | .. | .. | 6.0 | 5.5 | 6.0 | .. | .. | .. | 8.0 | [26] | ||
| 4482.3 | 0.0 | 4.0 | 4.6 | 6.0 | 5.5 | 6.7 | 8.0 | 7.2 | 8.1 | 8.3 | 8.6 | 9.0 | 7.7 | 8.0 | 7.6 | [27] | ||
| 4408.4 | 0.0 | 0.0 | 0.0 | 0.0 | 4.0 | 3.5 | 5.7 | 4.0 | 5.6 | 6.0 | 6.0 | 8.0 | 7.9 | 7.0 | 9.0 | [28] | ||
| 4352.7 | 0.0 | 2.0 | 4.0 | 5.0 | 4.3 | 6.3 | 7.4 | 5.0 | 7.3 | 8.1 | 8.0 | 7.0 | 8.1 | 8.0 | 9.0 | [29] | ||
| 4315-1 | 0.0 | 3.0 | 3.5 | 5.0 | 4.6 | 6.9 | 7.5 | 4.6 | 6.6 | 5.6 | 6.1 | 7.0 | 7.0 | 8.0 | 8.1 | [30] | ||
| 4282.4 | 0.0 | 0.0 | 0.0 | 0.0 | 5.0 | 3.0 | .. | .. | 4.0 | 5.0 | 6.1 | 5.0 | 6.0 | 8.0 | 4.4 | [31] | ||
| 4258.4 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 4.0 | 4.8 | .. | 4.5 | 5.2 | 4.3 | 4.5 | 5.3 | 10.0 | 4.0 | [32] | ||
| 4216.2 | 0.0 | 2.0 | 1.5 | 3.8 | 3.3 | 5.6 | 6.6 | 2.6 | 8.6 | 7.3 | 8.5 | 9.4 | 8.1 | 9.5 | 7.9 | [33] | ||
| 4134.3 | 0.0 | 0.0 | 0.0 | 3.0 | 2.0 | 4.0 | 3.5 | 4.5 | 5.5 | 5.2 | 5.6 | 7.0 | 7.0 | 5.0 | 5.5 | [34] | ||
| 3953 | unclas. | 0.0 | 0.0 | 2.0 | 5.3 | .. | 5.7 | 5.5 | .. | 8.0 | 8.0 | 7.5 | .. | .. | .. | .. | [35] | |
| 3999 | unclas. | 0.0 | 0.0 | 1.5 | 4.5 | 6.0 | 5.6 | 7.0 | 6.0 | 7.6 | 7.0 | 6.5 | .. | 7.0 | 8.0 | .. | [36] | |
| 4172 | unclas. | 0.0 | 2.0 | 3.0 | 4.6 | 4.6 | 6.3 | 9.0 | 5.7 | 7.3 | 5.8 | 6.4 | 7.3 | 6.0 | 9.0 | 8.2 | [37] | |
| 4401 | unclas. | 0.0 | 0.0 | 0.0 | 3.0 | 6.0 | 6.6 | 8.0 | 6.2 | 6.8 | 6.0 | 5.5 | 6.2 | 6.9 | 6.0 | 6.5 | [38] | |
| 4462 | unclas. | 0.0 | 0.0 | 0.0 | 0.0 | 3.0 | 2.0 | 4.2 | 5.0 | 6.0 | 6.0 | 6.0 | 6.3 | 6.5 | 7.2 | 7.0 | [39] | |
| 4476 | unclas. | 0.0 | 0.0 | 0.0 | 3.0 | 5.0 | 5.2 | .. | .. | 6.3 | 4.0 | 4.1 | 4.0 | 4.3 | 7.5 | 4.7 | [40] | |
| Fe+ | 4173.3 | 0.0 | 2.0 | 3.0 | 4.6 | 4.6 | 6.3 | 9.0 | 5.7 | 7.3 | 5.8 | 6.4 | 7.3 | 6.0 | 8.0 | 8.2 | [41] | |
| 4178.8 | 0.0 | 0.0 | 2.5 | 4.3 | .. | 6.8 | 9.1 | .. | 6.0 | .. | .. | .. | .. | .. | 6.5 | [42] | ||
| 4416.8 | 0.0 | 2.3 | 3.3 | 4.8 | 4.6 | 6.4 | 8.0 | 7.2 | 7.0 | 6.5 | 7.2 | 7.6 | 7.4 | 7.0 | 8.0 | [43] | ||
| Zn | 4810.5 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | tr | .. | tr | 1 | tr | 0 | .. | 0 | .. | .. | [1] | |
| 4722.2 | 0.0 | 0.0 | 0.0 | 0.0 | tr | tr | .. | tr | 1 | tr | 1- | .. | 1- | .. | .. | [2] | ||
| Sr | 4607.3 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 2.0 | 4.0 | .. | 7.0 | .. | 8.5 | 8.0 | 8.7 | 9.0 | 9.2 | [1] | |
| Sr+ | 4215.5 | .. | 2.0 | 1.5 | 3.8 | 3.3 | 5.6 | 6.6 | 2.6 | 8.6 | 5.3 | 8.5 | 9.4 | 8.1 | 8.0 | 7.9 | [2] | |
| 4077.7 | .. | 4.2 | 2.5 | 4.2 | 5.0 | 6.9 | 8.4 | 8.6 | 9.2 | 7.8 | 9.5 | 9.3 | 8.3 | 11.0 | 10.8 | [3] | ||
| Y+ | 4374.9 | 0.0 | 0.0 | 2.5 | 2.4 | 5.5 | 6.7 | 7.1 | .. | 7.8 | 6.7 | 6.9 | .. | 8.0 | 8.8 | 9.6 | [1] | |
| 4177.5 | 0.0 | 0.0 | 2.5 | 4.3 | .. | 6.8 | 9.1 | .. | 6.0 | .. | .. | .. | .. | .. | 6.5 | [2] | ||
| 4398. | .. | .. | .. | .. | .. | .. | .. | .. | 7.0 | .. | .. | 4.0 | 2.6 | 2.0 | 3.7 | [3] | ||
| Ba+ | 4554 | 0.0 | 0.0 | 2.0 | .. | .. | 4.0 | 4.7 | .. | 3.5 | 3.0 | 4.6 | 4.8 | 5.5 | 5.5 | 5.6 | [1] |
[NOTES ON OBSERVATIONAL MATERIAL]
NOTES TO TABLE XIX
| Atom | Note | Max. | Blends | Remarks |
|---|---|---|---|---|
| H | [1] | .. | No measures available across the whole range of these lines. They are blended with He+ in the types. For a discussion of the maximum of these lines, see [p. 166] | |
| [2] | .. | |||
| [3] | .. | |||
| [4] | .. | |||
| He | [1],[2],[3], 4 [5],[6],[7],[8] | .. | Maximum well determined. Unblended | |
| [4] | He+ | See Note 12 | ||
| [9],[10],[11],[12] | Probably blended. See H. C. 263, 1924 | |||
| C | [1] | .. | Unblended | |
| Mg | [1] | ? | .. | Effectively unblended. Material very meager |
| [2] | .. | Unblended | ||
| [3] | none | ; ; | Cr probably predominates | |
| [4] | -, ; | Fe predominates at lower temperature; Mg probably responsible for maximum | ||
| Al | [1] | none | .. | |
| [2] | none | .. | ||
| Si | [1] | -2; -1; ; -2; -1 | Si predominates, and is responsible for maximum | |
| [2] | ||||
| [3][4],[5] | .. | |||
| [6] | .. | |||
| [7] | N++ | |||
| [8] | ||||
| Ca | [1] | ; ; | Ca probably responsible for rise at | |
| [2] | Ca, ; ; Mn, ; ; | Ca probably predominates. Enhanced line suspected near | ||
| [3] | ; ; | Calcium predominates. Enhanced line suspected near | ||
| [4] | none | ; | In band | |
| [5] | none | ; ; -2; ; -2 | Maximum undetermined. In band | |
| [6] | ; -2; ; -1; Ti, Fe 4 | Fe probably responsible for maximum | ||
| [7] | ? | ; ; ; ; Ti; | Chromium (ultimate) line probably obliterates the Ca line. Maximum at due to Ca? | |
| [8] | ; | |||
| [9] | none | Unblended | ||
| [10] | ? | Hydrogen predominates before | ||
| [11] | ? | Unblended | ||
| Sc | [1] | Y? ; | Sc predominates, at least at maximum | |
| [2] | ; -2 | Sc predominates | ||
| Ti | [1] | ; V, | Blended with Ti+. See Note 10 | |
| [2] | (none) | ; ; ; -2; -2 | Ca causes rise at . Ti obliterated | |
| [3] | Ti+ causes rise at . Rise at unexplained | |||
| [4] | ; ; Ti, | |||
| [5] | () | ; ; Cr 5; ; ; | Ca and Cr cause rise at . Ti obliterated | |
| [6] | (none) | ; | Cr (ultimate) line predominates | |
| [7] | none | ; ; ; | Possibly an enhanced line accounts for maximum near ? | |
| [8] | (?) | ; | Mg accounts for maximum at | |
| [9] | (?) | Unblended | ||
| [10] | (?) | Ti, -5 | Probably unblended | |
| [11] | ; | Maximum at due to Fe | ||
| [12] | ? | ; V, | Blended with Ti. See Note 1 | |
| [13] | ? | ; ; | Fe predominates. Maximum uncertain | |
| [14] | ; | Rise at due to Fe. In band | ||
| [15] | ; | Rowland gives no Ti. Other lines account for later maximum. In band | ||
| [16] | ? | ; ; | Maximum undetermined. In band | |
| [17] | Unblended | |||
| [18] | (?) | ; ; | Cr accounts for strength in | |
| V | [1] | ; V, | Ti and Ti+ lines blended. V probably obliterated | |
| [2] | none | Unblended | ||
| [3] | none | Ti, ; | V probably effective at low temperatures, as these are the ultimate lines | |
| [4] | none | N; | ||
| Cr | [1] | Unblended | ||
| [2] | none | Nd? ; | Unblended | |
| [3] | none | ; ; ; | Cr probably predominates | |
| [4] | none | ; Cr ? | Cr predominates | |
| [5] | none | Unblended | ||
| Mn | [1] | none | Unblended | |
| [2] | none | ; | Fe predominates? | |
| [3] | none | ; ; Zr, -1 | ||
| [4] | none | ; Mn ? | Mn predominates | |
| [5] | none | Mn-Fe ? | ||
| [6] | none | Fe-Mn ? | ||
| [7] | Fe, ; ; | Mn predominates? | ||
| [8] | Fe-Mn 6 | |||
| [9] | ; Co, ; ; V, Ca ? | |||
| Fe | [1] | Mn-Fe | Effectively unblended | |
| [2] | () | , | No. 2 the weaker line, Mn+ affects the line at and before , producing maximum at . See No. 27 | |
| [3] | none | Fe-Mn, 3 ? | Effectively unblended | |
| [4] | none | Sc, Fe? 3; ; V, | Y+ accounts for maximum at | |
| [5] | - | Sr+ | Due entirely to Sr+ | |
| [6] | ? | ; ; -3 | Maximum at due to Fe+ | |
| [7] | Unblended | |||
| [8] | Unblended | |||
| [9] | () | ; ; | Ti+ () causes maximum at ; possibly Cr () causes rise at | |
| [10] | () | ; ; | Ti predominates? | |
| [11] | ; ; Ti, | Fe probably predominates | ||
| [12] | none | ; | Ca produces rise in late classes? | |
| [13] | Unblended. Rise at unexplained | |||
| [14] | Fe ? | Unblended. Rise at unexplained, unless due to second Fe line | ||
| [15] | ; | Rise at unexplained. See No. 25 | ||
| [16] | ; | |||
| [17] | ; -3 | Maximum at due to unknown line? | ||
| [18] | ; | |||
| [19] | ; | |||
| [20] | ; ; | Fe predominates | ||
| [21] | ; ? 3; ; -1, 1, 1 | |||
| [22] | ; Ti, ; | Rise at due to Ca? | ||
| [23] | ; | No. 23 the weaker line | ||
| [24] | ; ; | No. 24 the strongest line | ||
| [25] | See No. 15. Rise at unexplained | |||
| [26] | ? | ; | ||
| [27] | ; | The stronger line. Responsible also for the maximum of line 2 | ||
| [28] | ; ; ; ; | Rise at due to V | ||
| [29] | none | ; ; | Cr and Mn predominate. Cr (ultimate) line responsible for rise at | |
| [30] | ; | Maximum at due to Fe+ | ||
| [31] | ; | Ca produces rise at | ||
| [32] | ; ; | Rise at unexplained | ||
| [33] | Sr+ | Due entirely to Sr+ | ||
| [34] | - | ; Fe? 3; V-Fe?; | ||
| [35] | ? | ; Fe, -3; ; ; -, 1; Fe-Cr 3 | Too heavily blended | |
| [36] | Co ?; ; | Maximum at unexplained. Rise at due to Ti (ultimate line) | ||
| [37] | Cr, La, Mn, Ni, ; Ti, Fe2; Al?; Fe2 | See Rowland, p. 37. An Fe+ line responsible | ||
| [1][1] | ; ; | |||
| [39] | none | ; Fe, ; Nd? | Rise at unexplained | |
| [40] | () | ; | Rise at probably due to Ag | |
| [41] | ; ; -3; -3 | Maximum certainly due to Fe+. Neutral Fe causes rise in cool classes | ||
| [42] | ; -3; -1; -1N | Maximum due to ionized iron | ||
| [43] | ; | Maximum due to Fe+; later rise perhaps due to Mn | ||
| Zn | [1] | Unblended | ||
| [2] | Unblended | |||
| Sr | [1] | none | ; | Fe probably predominates, except perhaps at the lowest temperatures |
| [2] | ; Sr ?; Fe ? | Fe probably strong, but Sr responsible for part of maximum at | ||
| [3] | Fe, ; ; ; La, Nd? ; ; | Maximum uncertain owing to heavy blending | ||
| Y | [1] | ; -1; Sc, | Y+ gives the maximum | |
| [2] | ? | ; -3 | Maximum ill determined, but probably due to Y+ | |
| [3] | ? | -1 | Remark in Rowland:--in zircon but not in Zr | |
| Ba | [1] | none | Unblended |
CONSISTENCY OF RESULTS
The preceding tabulation summarizes the present state of the observational material bearing on the positions of the maxima of absorption lines. The comparison with theory is an important and difficult problem. The theoretical formulae contain as variables the temperature and the pressure; and the fractional concentration,
, is very sensitive to changes in both these variables. It would therefore be possible to satisfy almost any observations by varying the two quantities jointly; but this procedure would furnish no useful test of the theory. The test made in the present chapter will involve the calculation of the temperature scale, with the partial electron pressure,
, assumed constant.
Figure 8
Reproduced from H.C. 256, 1924. Comparison between observation and ionization theory for the hotter stars. The observations are contained in the upper part of the diagram, and the theoretical curves (based on a partial electron pressure
are given in the lower part of the figure. For the upper half, ordinates are the observed intensities contained in [Table XIX]; abscissae are spectral classes from the Draper Catalogue. In the lower part of the figure, ordinates are logarithms of computed fractional concentrations; abscissae are temperatures in thousands of degrees. The abscissae of the upper and lower diagrams have been adjusted so that the observed and computed maxima coincide, thus forming a preliminary temperature scale.
It is certain that this condition is not satisfied in practice, and a more rigorous treatment, which allows for the differences in partial electron pressure, is contained in the chapter that follows. But with the object of examining the consistency of the derived temperature scale, the present test is made under the assumption that the partial electron pressure is constant and equal to about
.
The resulting scale of temperatures for the reversing layers of the corresponding classes is contained in the table that follows. Successive columns contain the element that is utilized, the spectral class at which its lines attain maximum, and the corresponding temperature derived from the equations of [Chapter VII].
| Element | Maximum | Temperature | Element | Maximum | Temperature |
|---|---|---|---|---|---|
| He+ | 35000° | Ti | 3500° | ||
| Si+++ | 25000 | Mn | 5000 | ||
| Si++ | 18000 | Fe | 5000 | ||
| He | 10000 | V | 3500 | ||
| C+ | 16000 | Cr | 3500 | ||
| Si+ | 11000 | Sr+ | 6000 | ||
| H | 10000 | Ba+ | None | 5500 | |
| [*]Zn | 8000 | Ca | 4500 | ||
| [*]Ca+ | 6000 |
[*] Estimates by Menzel, H. C. 258, 1924.