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Spectral classifications in the near infrared of stars with composite spectra. III. Study of a sample of 137 objects with the Aurelie spectrograph We provide spectral classifications for a sample of 137 stars mentionedas having composite spectra. The classifications were carried out on 33Angstroms /mm spectra in the region 8370 - 8870 Angstroms. Of these 137objects, 115 correspond in the infrared to cool stars (G, K or M) ofluminosity classes III, II and I; for 22 stars, we find only hot spectraof types B, A, F or Am, so that they do not fulfil our definition ofcomposite spectra. We detect four new Am stars, and one Am star (HD70826) turns out to be a composite spectrum object. As in Paper II, thecool components of composite spectra show a strong concentration in thevicinity of G8III. Based upon observations carried out at Observatoirede Haute-Provence (OHP).
| Spectral classifications in the near infrared of stars with composite spectra. II. Study of a sample of 180 stars A sample of 180 supposedly composite-spectrum stars has been studied onthe basis of spectra obtained in the near infrared (8370-8780 Angstroms)at a dispersion of 33 Anstroms/mm. The objective was to study the coolercomponents of the systems. Of our sample, 120 are true compositespectra, 35 are hot spectra of types B, F and 25 are Am stars. We find astrong concentration of the cooler components of the composite spectraaround G8III. In view of the difficulty of classifying compositespectra, because of the super position of an early type dwarf and a latetype giant or supergiant spectrum, we have made several tests to controlthe classification based upon the infrared region. Since all tests gavepositive results, we conclude that our classifications can be consideredas being both reliable and homogeneous. Table \ref{tab1} is alsoavailable electronically at the CDS via anonymous ftp 130.79.128.5 orhttp://cdsweb.u-strasbg.fr/Abstracts.html} Based upon observationscarried out at Observatoire de Haute-Provence (CNRS).
| A survey of stars with composite spectra. Not Available
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Osservazione e dati astrometrici
Costellazione: | Cassiopea |
Ascensione retta: | 23h24m15.97s |
Declinazione: | +55°11'06.2" |
Magnitudine apparente: | 8.662 |
Distanza: | 1851.852 parsec |
Moto proprio RA: | -2.3 |
Moto proprio Dec: | -4.3 |
B-T magnitude: | 9.658 |
V-T magnitude: | 8.745 |
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