view Abstract Citations References Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Emission B stars in the association I Persei. Seyfert, Carl K. Abstract The Perseus association in the vicinity of the double cluster has a fairly well-established distance and is rich in Be stars. In an area 50 ~ centered on the double cluster, 49 Be stars have been catalogued by Merrill and Burwell (1933, 1943, 1949, 1950). Fourteen new Be stars from 10.4-13.8 mag were found on objective prism plates taken with the ~~-inch Baker-Schmidt telescope of the Arthur J. Dyer Observatory. New spectral classifications were made of the doubtful or missing cases where permissable. It was possible to obtain reliable spectral classifications of 45 Be stars. Photoelectric color excesses, E1, are available for only ii of the Be stars (Stebbins et aI., 1940). Since the absorption varies strongly across the association, color excesses were interpolated for the other Be stars using the photoelectric colors of the 52 B stars in the field. The visual absorption of 6.1 E1 (Morgan et al., i953a) was found for each star and applied to its observed apparent visual magnitude. If we adopt I i.8 as the value of the distance modulus of the association (Morgan et al., 1953b) the apparent magnitudes may be transformed to absolute magnitudes, under the assumption that the Be stars are in the aSS0ci~ti0n. The resulting H-R diagram for 45 Be stars was compared with a similar diagram of the B stars obtained by Bidelman (1943) with the following results: i) Essentially all Be stars in the field are in the Perseus association. 2) There is a small group of supergiant Be stars of the same absolute magnitudes as non-emission supergiant B stars in the association. 3) Most of the blue emission stars in the Perseus association are Boe to B5e with luminosities between III and V. 4) The non-emission B4 and B~ stars in the association seem to have the same absolute magnitude as the B~e and B5e stars. 5) The Boe to B~e stars are about one magnitude fainter than Bo to B3 stars in the association. 6) The average absolute visual magnitudes for the emission and non-emission Bo-B5 stars in the association I Persei are shown in the table below. The values in parentheses are numbers of stars. 53 Do- super- Bo.~ Ds B2 B3 54 B~ giants Emission -4.0 -3.5 -3.2 -3.3 -3.1 -2.7 -6.9 (4) (8) (9) (8) (3) (7) (3) Non-emission -4.9 -4.4 -5.0 -3.8 -3.3 -2.8 -6.8 (7) (6) (7) (8) (8) (~o) (3) This research was supported by a grant from the National Science Foundation. Bidelman, W. P. `943, Ap. J. 98, 61. Merrill, P. W. and Burwell, C. `933, Ap. J. 78, 87. and . `943, Ap. J. 98, 153. and . `949, Ap. J. 110, 387. and . 1950. Ap. J. 112, 72. Morgan, W. W., Harris, D. L. and Johnson, Fl. L. 1953a, Ap. J. ii8, 92. Morgan, W. W., Whitford, A. E. and Code, A. D. 1953b, Ap. J. ii8, 318. Stebbins, J., Huffer, C. M. and Whitford, A. E. 1940, Ap. J. 91, 20. Arthur J. Dyer Otservatory, Vanderbilt &niversity, Nashville, Tenn. Publication: The Astronomical Journal Pub Date: June 1955 DOI: 10.1086/107206 Bibcode: 1955AJ.....60..177S full text sources ADS | data products SIMBAD (1)