We next will validate our classifications obtained from Aurelie with proceeding from Carelec. Then we shall confront our classifications with those of the "standard" CS, that is, stars which possess a classification which we consider trustworthy (see Paper II, 4.1). And finally we shall confront, for a small sample, our results with those published in the Michigan catalogues (Houk 1982; Houk & Smith-Moore 1988).
a) Comparison Carelec-Aurelie
A comparison of the 51 stars observed with both spectrographs permits to isolate 22 stars for which
the results are identical. These are: HD 4775 (G7III) - 17878 (G7III)
- 21771 (K3II) - 23089 (G2Ib) - 25555 (K1II) - 26630 (G0Ib) - 26673 (G9II)
- 29094 (G7Ib) - 39118 (K0II) - 66094 (G9III-IV) - 74395 (G1Ib) -
88021 (G8III) - 166479 (G8III) - 169985 (G9III) - 184759 (G8III) -
187259 (G8III) - 193410 (K0III) - 193495 (G9II) - 197177 (G8II) -
200428 (K0III) - 205114 (G2Ib) -
213310 (K6-M0I). These objects do not figure in Table 2,
except HD 4775 and HD 25555 for which
recent classifications exist, obtained on
the basis of the method of substraction of spectra
(Griffin R&R 1986).
For the other 29 stars one perceives small
differences in spectral type and luminosity
classes (Fig. 4), but without a systematic trend.
The average scatter around the linear relations
corresponds to about 0.7 tenth of a spectral
type and 0.3 luminosity class. Both errors are within the
normal precision of spectral types
(Jaschek & Jaschek 1987).
b) Comparison with the so called "standards" CS
We have made the inventory of CS stars for
which a satisfactory classification exists (see Paper II).
The complete list is as follows: HD 4775, 17878, 25555, 26630, 29094,
57146, 74395, 88021,
169689, 173764, 184759, 187076, 187259,
187299, 190161, 192713, 200428, 200905, 201270, 205114.
Of this list 13 have classifications obtained by R&R Griffin
by the so called method of
substraction of spectra and six others are
MK standards.
c) Comparison with the classification of the Michigan catalogues
Our complete sample (Papers II and III)
contains 25 stars of the southern hemisphere which figure
in the catalogues of Michigan: HD 29961, 35162, 47579,
51250, 57146, 59076, 60414, 70442,
74946, 75098, 79267, 84367, 95235, 102171,
120901, 137975, 167570, 168701, 169652, 173805,
174191, 193495, 209278, 218640, 223932.
In Fig. 6 we compare their and our classifications, for spectral types and luminosity classes respectively. We notice that for HD 209278 Houk does not provide the luminosity classification.
The spectra classed by Houk were obtained with the objective prism, on IIaO plates, dispersion
108 Å/mm at H and a resolution near to 2 Å.
If one takes into account the difficulties in classifying CS
in this wavelength region (see Paper I),
the agreement with our classifications is very good for the
spectral types. On the average, the
Michigan classifications are slightly later than ours for type G
and slightly earlier for type K. For
luminosity classes the agreement is excellent for class III, but in
disagreement for classes I and II.
From five stars classed II by us, four are classed III by Houk and
two stars classed I by us are classed II and III by Houk.
Copyright The European Southern Observatory (ESO)