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Probing disk inhomogeneities using spectropolarimetry in the extreme binary epsilon Aurigae

Published online by Cambridge University Press:  24 July 2015

Kathleen Geise  and
Robert Stencel
Kathleen Geise
Affiliation:
University of Denver, 2112 East Wesley Avenue, Denver, Colorado 80208, USA email: kgeise@du.edu
Robert Stencel
Affiliation:
University of Denver, 2112 East Wesley Avenue, Denver, Colorado 80208, USA email: kgeise@du.edu
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Abstract

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The ϵ Aurigae system is a single–line spectroscopic binary system that consists of a variable F0 supergiant star and an occulting disk surrounding an unseen object, probably a B star. The eclipse occurs every 27 years and lasts for almost 2 years. Spectral features attributed to the disk exhibit line shifts due to the rotation of the disk that are easily observed in spectra. We obtained 50+ epochs of high dispersion optical spectropolarimetric data from the ESPaDOnS instrument at the Canada–France–Hawaii Telescope before, during, and after the most recent eclipse (2009–2011). We found numerous 3–sigma (or greater) linear polarization features in the spectra and associated these with atomic absorption features also present in the spectra. We observed dramatic changes to polarization and position angles with time during eclipse, particularly around 3rd contact. The increased polarization could be due to a localized increased number of scatterers.

Keywords

binaries: eclipsingline: identificationpolarizationaccretion disks
Type
Contributed Papers
Information
Proceedings of the International Astronomical Union , Volume 10 , Symposium S305: Polarimetry: From the Sun to Stars and Stellar Environments , December 2014 , pp. 293 - 298
Copyright
Copyright © International Astronomical Union 2015 

References

Bagnulo, S., Landolfi, M., Landstreet, J. D., Landi Degl'Innocenti, E., Fossati, L., & Sterzik, M. 2009, PASP 121, 993 Google Scholar
Cole, G. M. 2012, The Journal of the American Association of Variable Star Observers 40, 787 Google Scholar
Donati, J.-F., Semel, M., Carter, B. D., Rees, D. E & Collier Cameron, A. 1997, MNRAS 291, 658 Google Scholar
Donati, J.-F. 2003, in: Trujillo Bueno, J. & Sánchez Almeida, J. (eds.), Proc. Solar Polarization (ASP-CS), 307, p. 41Google Scholar
Geise, K., Stencel, R. E., Manset, N., Harrington, D., & Kuhn, J. 2012, The Journal of the American Association of Variable Star Observers 40, 767 Google Scholar
Harrington, D. M. & Kuhn, J. R. 2009, ApJS 180, 138 CrossRefGoogle Scholar
Hoard, D. W., Howell, S. B., & Stencel, R. E. 2010, ApJ 714, 549 Google Scholar
Kloppenborg, B., Stencel, R., Monnier, J. D., Schaefer, G., Zhao, M., Baron, F., McAlister, H., ten Brummelaar, T., Che, X., Farrington, C., Pedretti, E., Sallave-Goldfinger, P. J., Sturmann, J., Sturmann, L., Thureau, N., Turner, N., & Carroll, S. M. 2010, Nature 464, 870 Google Scholar
Lambert, D. L. & Sawyer, S. R. 1986, PASP 98, 389 CrossRefGoogle Scholar
Leadbeater, R., Buil, C., Garrel, T., Gorodenski, S. A., Hansen, T., Schanne, L., Stencel, R. E, & Stober, B. 2012, The Journal of the American Association of Variable Star Observers 40, 729 Google Scholar
Mauclaire, B., Buil, C., Garrel, T., Leadbeater, R., & Lopez, A. 2012, The Journal of the American Association of Variable Star Observers 40, 718 Google Scholar
Stefanik, R. P., Torres, G., Lovegrove, J., Pera, V. E., Latham, D. W., Zajac, J., & Mazeh, T. 2010, AJ 139, 1254 Google Scholar
Strassmeier, K. G., Weber, M., Granzer, T., Schanne, L., Bartus, J., & Ilyin, I. 2014, AN 335, 904 Google Scholar