Catalogue and Bibliography of Stars of Classes B and A whose Spectra have Bright Hydrogen Lines
Abstract
The main catalogue, Table I, lists 410 stars of classes 0, B, and A whose spectra have bright hydrogen lines, while Table II gives six anomalous objects whose spectra have bright lines of hydrogen and helium, but whose absorption spectra include titanium oxide bands. The exact meaning of the word "bright" as applied to lines having com- plex structure is discussed in the introduction. Notes to Table I record considerable unpublished data, besides calling attention to the chief features of a few of the more interesting peculiar spectra. The bibliography includes 365 references to observational material concerning the objects in Tables I and II. The items referring to each star are indicated in a key list. Discussion-The numbers of stars discovered at various observatories are in Table IV. Tables V and VT show the distribution in type and magnitude. The largest num- bers are in subdivision B3 and magnitude 8. Stars of the P Cygni type are listed in Table VII. Tables VIII, IX, X, and XI compare the numbers of Be stars in various intervals of type and magnitude with the total numbers of H.D. stars in the same in- tervals. Stars of class B 2 have a stronger tendency toward emission than those of either earlier or later subdivisions. The proportion of bright-line stars decreases very rapidly from B3 to Ao. The galactic distribution of Be stars is shown by Figs. 2a, 2b, and ~. The divergence from the galactic plane characteristic of the local system is less strongly marked than for non-emission B stars, probably because the emission stars are some- what brighter intrinsically. Table XIII lists i 2 areas rich in Be stars, among which star groups of two types may be recognized. An extremely interesting region is that of the double cluster in Perseus. The distribution of faint Cepheids is similar to that of faint Be stars. INTRODUCTIO
- Publication:
-
The Astrophysical Journal
- Pub Date:
- September 1933
- DOI:
- 10.1086/143490
- Bibcode:
- 1933ApJ....78...87M