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Pressure Shifts of Metal Lines in Cool White Dwarfs

Published online by Cambridge University Press:  12 April 2016

Gordon L. Hammond*
Affiliation:
Astronomy Program,Department of MathematicsUniversity of South Florida,Tampa, FL 33620

Abstract

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Model atmosphere techniques and an experimentally confirmed theory of collision broadening of CaII H and K by helium have been combined to shou that the difference in velocity shifts for the two lines is a sensitive diagnostic for the H/He abundance ratio in cool, metallic line uhite dwarfs.

Type
Research Article
Copyright
Copyright © Springer-Verlag 1989

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