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arXiv · 1707.06835

Precise surface gravities of $\delta$ Scuti stars from asteroseismology

A. García Hernández·J. C. Suárez·A. Moya·Mário J. P. F. G. Monteiro·Z. Guo·D. R. Reese·J. Pascual-Granado·S. Barceló Forteza·S. Martín-Ruiz·R. Garrido·J. Nieto
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Abstract

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.

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A. García Hernández, J. C. Suárez, A. Moya, Mário J. P. F. G. Monteiro, Z. Guo, D. R. Reese, J. Pascual-Granado, S. Barceló Forteza, S. Martín-Ruiz, R. Garrido, J. Nieto. 2017-07-21. Precise surface gravities of $\delta$ Scuti stars from asteroseismology. https://doi.org/10.1093/mnrasl/slx117

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