Bibcode
Creevey, O. L.; Metcalfe, T. S.; Brown, T. M.; Jiménez-Reyes, S.; Belmonte, J. A.
Bibliographical reference
The Astrophysical Journal, Volume 733, Issue 1, article id. 38 (2011).
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5
2011
Journal
Citations
7
Refereed citations
4
Description
Many stars exhibit stellar pulsations, favoring them for asteroseismic
analyses. Interpreting the oscillations requires some knowledge of the
oscillation mode geometry (spherical degree, radial, and azimuthal
orders). The δ Scuti stars (1.5-2.5 M sun) often show
just one or few pulsation frequencies. Although this may promise a
successful seismological analysis, we may not know enough about either
the mode or the star to use the oscillation frequency to improve the
determination of the stellar model or to probe the star's structure. For
the observed frequencies to be used successfully as seismic probes of
these objects, we need to concentrate on stars for which we can reduce
the number of free parameters in the problem, such as binary systems or
open clusters. We investigate how much our understanding of a δ
Scuti star is improved when it is in a detached eclipsing binary system
instead of being a single field star. We use singular value
decomposition to explore the precision we expect in stellar parameters
(mass, age, and chemical composition) for both cases. We examine how the
parameter uncertainties propagate to the luminosity-effective
temperature diagram and determine when the effort of obtaining a new
measurement is justified. We show that for the single star, a correct
identification of the oscillation mode is necessary to produce strong
constraints on the stellar model properties, while for the binary system
the observations without the pulsation mode provide the same or better
constraints on the stellar parameters. In the latter case, the strong
constraints provided by the binary system not only allow us to detect an
incorrectly identified oscillation mode, but we can also constrain the
oscillation mode geometry by comparing the distribution of possible
solutions with and without including the oscillation frequency as a
constraint.
Related projects
Helio and Astero-Seismology and Exoplanets Search
The principal objectives of this project are: 1) to study the structure and dynamics of the solar interior, 2) to extend this study to other stars, 3) to search for extrasolar planets using photometric methods (primarily by transits of their host stars) and their characterization (using radial velocity information) and 4) the study of the planetary
Savita
Mathur