Studies of the Large Magellanic Cloud stellar content: III. Spectral types and V magnitudes of 1822 members.

The presently known supergiants belonging to the Large Magellanic Cloud have been collected in the main published catalogues (Sanduleak 1969, Fehrenbach and Duflot 1970) and in more restricted surveys made by different authors. The result consists in a catalogue containing more than 1800 objects among which 30 or so only are very likely extended objects. A spectral survey has been made during the period 1971 to 1975 with the ESO 40 cm astrograph at La Silla, equipped with its normal prism, giving an intermediate dispersion of 95 A mm ' at X 4026 A. Long exposure plates taken directly or with an interference filter enabled us to obtain spectral types for nearly 1600 stars. In parallel, a V photographic survey has been carried out during the same period with the same astrograph and has led to the determination of V magnitudes for more than 700 stars having no previous photometric data. New spectroscopic and photometric results as well as previous photoelectric UBV values are given in the catalogue together with additional remarks concerning peculiarities of spectra, V magnitudes, and details on double or multiple systems. Key words. Large Magellanic Cloud - supergiants - spectral classification - UBV photometry