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Four Color Photometry of DB White Dwarfs

Published online by Cambridge University Press:  12 April 2016

Gary Wegner
Gary Wegner*
Affiliation:
Department of Physics, 223 Sharp Laboratory, University of Delaware, Newark, Delaware 19711

Extract

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Observations of 22 DB stars using the uvby photometric system are discussed. In the [(b–y),(u–b)] diagram, these objects define a relatively tight sequence, but the interpretation is hampered by the lack of a precise knowledge of atmospheric element abundances in these stars. The recent models of Koester (1979) show a larger gravity separation for the DB’s using Strömgren photometry and appear to fit the observations better than earlier theoretical results. Due to the tightness of the DB sequence at the hot and cool ends, respectively, there appears to be evidence for restricted ranges in log g and the atmospheric hydrogen abundance.

Type
Colloquium Session IV
Information
International Astronomical Union Colloquium , Volume 53: White Dwarfs and Variable Degenerate Stars , August 1979 , pp. 250 - 254
Copyright
Copyright © The University of Rochester 1979

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