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Description
The two papers compiled here contain spectral types for about 2600 stars in two regions near +20 deg and +40 deg galactic latitude at far-northern Declination. The +20 deg latitude region extends from about RA 19h30m to 0h00m; the +40 deg latitude region extends from about RA 10h to 15h45m. Each zone is about 5 deg in width and the faintest stars are about V mag 11. This includes nearly all BD stars plus many fainter ones. A statistical study of these stars was presented in a third paper (1954ArA.....1..483S). The source material consists of objective-prism plates taken between 1934 and 1940 with the Zeiss-Heyde astrograph (15cm aperture f/10 triplet) of the Uppsala Observatory. The 9.7-deg prism gave a dispersion of 1.4mm between H-gamma and H-epsilon, roughly 260A/mm. The stars were classified on the basis of microphotometer tracings of the spectra. For the present list only the spectral types have been preserved, and various magnitudes, line-ratios, and color-equivalents omitted. The coordinates are mainly from Tycho-2. The magnitudes close to standard V are from modern sources including Tycho-2 and the TASS MkIV survey. The Uppsala spectral types are expressed in MK notation, specifically relating to dwarf/giant discrimination via the CN bands for G and K stars, and some luminosity classification via Balmer line-widths for stars between late-B and early-A. In principle, the temperature types are matched to the HD scale. A few "new" metallic-line A-type stars are reported here as well. In addition, two mag 10 stars were identified by Schalen as type 'B'. Examination of Burrell Schmidt objective-prism plates (uv-transparent 10-degree prism, 110A/mm) shows that both are previously unrecognized B subdwarfs (BD+74 435 and BD+77 564 in the latitude +40 zone). The catalogue contains many stars not classified, for instance, in the HD or for the Yale and AGK astrometric catalogues. Similarly, large numbers of BD stars without accurate coordinates are identified here for the first time. Non-BD stars are assigned the acronyms [S48] and [S49]. There are several clerical errors in the published tables such that stars are either not the named BD star or are not recovered near the nominal coordinates. A combination of the spectral types and more recent photometric colors was used to identify candidates within about 10' radius, but a few stars remain lost.
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