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Cluster analysis of the hot subdwarfs in the PG survey

Published online by Cambridge University Press:  12 April 2016

Peter Thejll ,
Darryl Charache  and
Harry L. Shipman
Peter Thejll
Affiliation:
Department of Physics and Astronomy, University of Delaware, Newark, DE 19716.
Darryl Charache
Affiliation:
Department of Physics and Astronomy, University of Delaware, Newark, DE 19716.
Harry L. Shipman
Affiliation:
Department of Physics and Astronomy, University of Delaware, Newark, DE 19716.

Extract

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The Palomar Green survey (Green et al., 1986) of faint blue, high galactic-latitude objects, turned up several interesting new classes of objects, such as gravitational lenses (Weyman et al., 1980), the ultra hot star H1504+65 (Nousek et al., 1986), and the PG 1159-035 variables (McGraw et al., 1979). The PG survey forms a mainstay in the investigations of late stages of stellar evolution. Work (Flemming et al., 1986) has already cast light on the important question of the space density of DA’s and continuing work is seeking values for similar population parameters for the subdwarfs: Evolutionary links between the subdwarf stage and white dwarfs will thereby be illuminated.

Type
Research Article
Information
International Astronomical Union Colloquium , Volume 114: White Dwarfs , 1989 , pp. 130 - 133
Copyright
Copyright © Springer-Verlag 1989

References

Green, R., Schmidt, M., and Liebert, J. The Palomar-Green Catalog of Ultraviolet-Excess stellar objects. Astrophysical Journal Supplement Series, 1986, 61, 305–352.Google Scholar
Weyman, R.J., Latham, D., Angel, J.R.P., Green, R.F., Liebert, J.W., Turnshek, D.A., Turnshek, D.E., and Tyson, J.A. The triple QSO PG1115+08: another probable gravitational lens. Nature, 1980, 285, 641.CrossRefGoogle Scholar
Nousek, J.A., Shipman, H.L., Holberg, J.B., Liebert, J.W., Pravdo, S., White, N.E., and Giommi, P. H1504+65: An Extraordinary Hot Compact Star Devoid of Hydrogen and Helium. Astrophysical Journal, 1986, 309, 230–240.Google Scholar
McGraw, J.T., Starrfield, S.G., Liebert, J., and Green, R. PG1159-035: A New, Hot, non-DA Pulsating Degenerate. In Van Horn, H. and Weidemann, V.. (Eds.), Proceedings of IAU Colloquium No. 53: White Dwarfs and Variable Degenerate Stars. IAU, 1979.Google Scholar
Flemming, T.A., Liebert, J., Green, R.F. The luminosity function of DA white dwarfs. Astrophysical Journal, 1986, 308, 176–189.CrossRefGoogle Scholar
Wishart, D. CLUSTAN User Manual (Third ed.). Inter-University/Research Councils Series, Report No 47, 1982.Google Scholar
Hunger, K., Gruschinske, J., Kudritzki, R.P., Simon, K.P. NON-LTE Analysis of Sublummous O-stara. IV Spectral Photometry and NLTE Analysis of 11 Subluminous Stars. Astronomy and Astrophysics, 1981, 95, 244–249.Google Scholar