Precise surface gravities of $δ$ Scuti stars from asteroseismology [SSA]

http://arxiv.org/abs/1707.06835


The work reported here demonstrates that it is possible to accurately determine surface gravities of $\delta$ Sct stars using the frequency content from high precision photometry and a measurement of the parallax. Using a sample of 10 eclipsing binary systems with a $\delta$ Sct component and the unique $\delta$ Sct star discovered with a transiting planet, WASP-33, we were able to refine the $\Delta\nu-\bar\rho$ relation. Using this relation and parallaxes, we obtained independent values for the masses and radii, allowing us to calculate the surface gravities without any constraints from spectroscopic or binary analysis. A remarkably good agreement was found between our results and those published, extracted from the analysis of the radial velocities and light curves of the systems. This reinforces the potential of $\Delta\nu$ as a valuable observable for $\delta$ Sct stars and settles the degeneracy problem for the $\log g$ determination through spectroscopy.

Read this paper on arXiv…

A. Hernandez, J. Suarez, A. Moya, et. al.
Mon, 24 Jul 17
25/42

Comments: 5 pages, 2 figures, 1 table