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Spectral Classification of Early Type Stars from the Low Dispersion Ultraviolet Spectra

Published online by Cambridge University Press:  30 March 2016

K. Nandy*
Affiliation:
Royal Observatory, Edinburgh

Extract

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The methods of spectral classification from the low dispersion ultraviolet spectra obtained with the S2/68 experiment in the TD1 satellite have been described. The bright stars, the spectra of which are photometrically accurate, can be divided into natural groups according to the spectral appearance of the features. These features vary in strength with spectral type and luminosity, and enable separation between main sequence and luminous stars. The limits for these stars are at BO to at AO. For fainter stars the spectral data have been combined to obtain narrow band magnitudes at several wavelengths. These photometric bands have an effective width of 100 A. An ultraviolet photometric system which enables determinations of spectral type and luminosity of early type stars is described and the results for about 3000 stars is presented. The photometric system considered here consists of the ultraviolet colour indices (m2740−V,) (m2190−V) and (m1490−V).

Type
Joint Dicussions
Copyright
Copyright © Reidel 1977

References

Blanco, V. M., Demers, S., Douglass, G. G., Fitzgerald, M. P. 1968, Pub. U.S. Naval Obs. Vol. 21.Google Scholar
Boksenberg, A., Evans, R. G., Fowler, R. G., Gardner, I. S. K., Houziaux, L., Humphries, C. M., Jamar, C., Macau, D., Macau, J. P., Malaise, D., Monfils, A., Nandy, K., Thompson, G. I., Wilson, R., Wroe, H. 1973, Mon. Not. R. astr. Soc. 163, 291.Google Scholar
Cucchiaro, A., Jaschek, M., and Jaschek, C. 1976, Astron. and Astrophys. (in press).Google Scholar
Houziaux, L. 1976, (in preparation)Google Scholar
Humphries, C. M., Nandy, K., Kontizas, E. 1975. Astrophys, J., 195, 111.Google Scholar
Humphries, C. M. Jamar, C., Malaise, D., and Wroe, H. 1976, Astron. and Astrophys, 49, 389.Google Scholar
Jamar, C., Praderie, F and Macau-Hercot, D. 1976, (in preparation)Google Scholar
Nandy, K., Humphries, C. M. and Thompson, G. I. 1975, I.A.U. Symposium No. 72 (Lausanne).Google Scholar
Nandy, K., and Schmidt, E. G. 1975, Astrophys. J., 198, 119.Google Scholar
Nandy, K., Jamar, C., Monfils, A., Thompson, G. I., Wilson, R. 1976, Astron and Astrophys., 51, 63.Google Scholar
Oke, J. B., and Schild, R. E. 1970, Astrophys. J., 161, 1015.Google Scholar