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Description
The catalog contains MK spectral classifications for 1003 HD stars in the zone +25-30{deg}, briefly presented at IAU Colloq. 47, held in Vatican City in July 1978 (1979RA......9..479C). Most stars classified in this region are earlier than G2. The notation is the same as in the earlier paper (1981A&AS...45..455J), with conventions similar to the Houk and Cowley survey (Cats. III/31 and III/51); a noticeable exception is that the luminosity class the most probable stands before the slash. On the average, the classifications present in the catalogue are means of 3 classifications. The internal rms error estimated by the author on a single classification is typically: {sigma}(SpT) = 0.65 (unit 1 subtype) {sigma}(Lum) = 0.40 (unit lum. class) No dependence on spectrum quality is found; however the quality 4 spectra are seldom classified without slashes (which introduces a sort of "internal scatter" into the type) External errors were estimated by a comparison with published work: - Walborn (1971ApJS...23..257W) and Guetter (1968PASP...80..197G) concern early-B stars; - Cowley et al. (1969AJ.....74..375C) and Osawa (1959ApJ...130..159O) concern late-B and A stars; - Harlan et al. (1969AJ.....74..916H, 1970AJ.....75..165H), Hill et al. (1976MmRAS..82...69H) and Heard (1956PDDO....2..105H) concern F stars; - Fehrenbach lists concern all type stars. The comparisons give the following external errors: ----------------------------------------------------- Source N D(SpT) +/- D(Lum) +/- ----------------------------------------------------- Walborn (1971) 5 -.40 +/- .45 -.10 +/- .32 Guetter (1968) 4 -.12 +/- .25 -.12 +/- .25 Cowley et al. 17 -.52 +/- .72 -.09 +/- .53 Osawa (1959) 18 -.22 +/- .77 -.22 +/- .77 Harlan et al. 20 +.20 +/- .69 +.03 +/- .56 Hill et al. 18 -.36 +/- .78 -.19 +/- .55 Heard (1956) 46 -.24 +/- .88 +.10 +/- .47 Fehrenbach et al. 46 +.48 +/-1.39 +.34 +/-1.06 ----------------------------------------------------- These figures should be compared with e.g. Heck and Mersch (1980A&A....83..287H, 1980A&A....85...93M), Cowley et al. (1969AJ.....74..375C), Cowley (1976PASP...88...95C), or Abt (1981ApJS...45..437A)
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