Bibcode
Metcalfe, T. S.; Chaplin, W. J.; Appourchaux, T.; García, R. A.; Basu, S.; Brandão, I.; Creevey, O. L.; Deheuvels, S.; Doǧan, G.; Eggenberger, P.; Karoff, C.; Miglio, A.; Stello, D.; Yıldız, M.; Çelik, Z.; Antia, H. M.; Benomar, O.; Howe, R.; Régulo, C.; Salabert, D.; Stahn, T.; Bedding, T. R.; Davies, G. R.; Elsworth, Y.; Gizon, L.; Hekker, S.; Mathur, S.; Mosser, B.; Bryson, S. T.; Still, M. D.; Christensen-Dalsgaard, J.; Gilliland, R. L.; Kawaler, S. D.; Kjeldsen, H.; Ibrahim, K. A.; Klaus, T. C.; Li, J.
Bibliographical reference
The Astrophysical Journal Letters, Volume 748, Issue 1, article id. L10 (2012).
Advertised on:
3
2012
Citations
153
Refereed citations
126
Description
The evolved solar-type stars 16 Cyg A and B have long been studied as
solar analogs, yielding a glimpse into the future of our own Sun. The
orbital period of the binary system is too long to provide meaningful
dynamical constraints on the stellar properties, but asteroseismology
can help because the stars are among the brightest in the Kepler field.
We present an analysis of three months of nearly uninterrupted
photometry of 16 Cyg A and B from the Kepler space telescope. We extract
a total of 46 and 41 oscillation frequencies for the two components,
respectively, including a clear detection of octupole (l = 3) modes in
both stars. We derive the properties of each star independently using
the Asteroseismic Modeling Portal, fitting the individual oscillation
frequencies and other observational constraints simultaneously. We
evaluate the systematic uncertainties from an ensemble of results
generated by a variety of stellar evolution codes and fitting methods.
The optimal models derived by fitting each component individually yield
a common age (t = 6.8 ± 0.4 Gyr) and initial composition (Z
i = 0.024 ± 0.002, Y i = 0.25 ±
0.01) within the uncertainties, as expected for the components of a
binary system, bolstering our confidence in the reliability of
asteroseismic techniques. The longer data sets that will ultimately
become available will allow future studies of differential rotation,
convection zone depths, and long-term changes due to stellar activity
cycles.
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