In a preceding paper (Ginestet et al. 1994) we have shown that the near infrared region (8370-8780 Å) is interesting for classifying the cooler components of composite spectra. This is essentially due to the fact that whereas in the blue spectral region (3800-4800 Å) the magnitude difference between both components is about zero (i.e. both spectra are hopelessly intermingled), in the near infrared region the magnitude difference is more favorable to the cooler component. Very frequently the traces of the early type companion can only be perceived faintly through the presence of weak hydrogen lines of the Paschen series.
Let us recall here briefly that we shall call composite spectra all those resulting from the combination of the spectra of a hot early type dwarf (type B or A) and that of a late type subgiant, giant or even supergiant object (types G, K or M).
The first paper (Paper I) was devoted to the study of a sample of 92 MK standards, which permitted to establish the classification criteria for this region, using the equivalent widths of certain lines or blends of lines. For early type spectra we have used essentially the Paschen lines P12 and P14 of hydrogen, the CaII lines 8498, 8542 and the OI line 8446. For the late type spectra we have used mainly the CaII triplet lines (8498, 8542, 8662 Å), the FeI (8621, 8688 Å), TiI (8426, 8435 Å) lines and the blend 8468. The latter is constituted by a blend of lines of iron and titanium but contains also some faint lines of CN, Mg and Zr.
In the present paper (Paper II) we apply the results of Paper I to a sample of stars with composite spectra.
We have provided in Paper I a list of papers written on both the near infrared spectral region and on composite spectra. We shall not repeat here these references, but complete the list given with some papers published recently. The most important additions are four new atlases covering the near infrared. The first is by Torres-Dodgen & Weaver (1993) which covers the 5800-8900 Å region at a resolution of about 15 Å. The second atlas is the one by Danks & Dennefeld (1994) covering the region 5800- 10200 Å at a dispersion of 171 Å/mm. The third atlas (Andrillat et al. 1995) covers the 8400-8800 Å region of early type stars at a dispersion of 33 Å/mm and the fourth is by ourselves (Carquillat et al. 1997). It covers the same region as the third atlas and uses the same dispersion but deals only with late type stars. We mention also a recent paper by Weaver & Torres-Dodgen (1995) on an automated classification of A type stars in the near infrared.
Table 1: Classifications of the cool components, SP(IR), of stars with composite spectra
Table 2: Stars of the sample which exhibit a hot spectrum
