Due to the short settling times of metals in DA white dwarf atmospheres, any white dwarfs with photospheric metals must be actively accreting. It is therefore natural to expect that the metals may not be deposited uniformly on the surface of the star. We present calculations showing how the temperature variations associated with white dwarf pulsations lead to an observable diagnostic of the surface metal distribution, and we show what constraints current data sets are able to provide. We also investigate the effect that time-variable accretion has on the metal abundances of different species, and we show how this can lead to constraints on the gravitational settling times.
The Astrophysical Journal Letters
The American Astronomical Society, The Institute of Physics
Grant or Award Name
National Science Foundation awards AST-0507639 and AST-0607480
Scholarly Commons Citation
Montgomery, M. H., Thompson, S., & von Hippel, T. (2008). Constraining the Surface Inhomogeneity and Settling Times of Metals on Accreting White Dwarfs. The Astrophysical Journal Letters, 685(2). Retrieved from https://commons.erau.edu/publication/1132