Hostname: page-component-848d4c4894-8kt4b Total loading time: 0 Render date: 2024-06-14T21:38:12.869Z Has data issue: false hasContentIssue false

Starspots properties and stellar activity from planetary transits

Published online by Cambridge University Press:  12 September 2017

Adriana Valio*
Affiliation:
Center for Radio Astronomy and Astrophysics (CRAAM)Mackenzie Presbyterian University, Sao Paulo, Brazil email: avalio@craam.mackenzie.br
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Magnetic activity of stars manifests itself in the form of dark spots on the stellar surface. This in turn will cause variations of a few percent in the star light curve as it rotates. When an orbiting planet eclipses its host a star, it may cross in front of one of these spots. In this case, a “bump” will be detected in the transit lightcurve. By fitting these spot signatures with a model, it is possible to determine the spots physical properties such as size, temperature, location, magnetic field, and lifetime. Moreover, the monitoring of the spots longitude provides estimates of the stellar rotation and differential rotation. For long time series of transits during multiple years, magnetic cycles can also be determined. This model has been applied successfully to CoRoT-2, CoRoT-4, CoRot-5, CoRoT-6, CoRoT-8, CoRoT-18, Kepler-17, and Kepler-63.

Type
Contributed Papers
Copyright
Copyright © International Astronomical Union 2017 

References

Baliunas, S. A., Donahue, R., Soon, W., Horne, J., Frazer, J., Woodard-Eklund, L., Bradford, M., Rao, L., Wilson, O., Zhang, Q., et al., 1995, ApJ, 438, 269 Google Scholar
Christiansen, J. L., Jenkins, J. M., Caldwell, D. A., Burke, C. J., Tenenbaum, , et al. 2012, PASP, 124, 1279 CrossRefGoogle Scholar
Dicke, R. H., 1970, ApJ, 159, 25 CrossRefGoogle Scholar
Estrela, R. & Valio, A., 2016, ApJ, 831, 57 CrossRefGoogle Scholar
Messina, S. & Guinan, E. F., 2002, A&A, 393, 225 Google Scholar
Olah, K., Kollath, Z., Granzer, T., Strassmeier, K. G., Lanza, A. F. et al., 2009, A&A, 501, 703 Google Scholar
Oshagh, M., Santos, N. C., Ehrenreich, D., Haghighipour, N., Figueira, P., Santerne, A., & Montalto, M., 2014, A&A, 568, A99.Google Scholar
Pont, F., Sing, D. K., Gibson, N. P., Aigrain, S., Henry, G., & Husnoo, N., 2013, MNRAS, 432, 2917 Google Scholar
Saar, S. H. & Brandenburg, A., 1999, ApJ, 524, 295 Google Scholar
Sanchis-Ojeda, R. & Winn, J. N., 2011, ApJ, 743, 61 Google Scholar
Sanchis-Ojeda, R., Fabrycky, D. C., Winn, J. N., Barclay, T., Clarke, B. D., Ford, E. B. et al., 2012, Nature, 487, 449 CrossRefGoogle Scholar
Silva, A. V. R., 2003, ApJ (Letters), 585, L147 CrossRefGoogle Scholar
Silva-Valio, A., 2008, ApJ (Letters), 683, L179 CrossRefGoogle Scholar
Silva-Valio, A., Lanza, A. F., Alonso, R., & Barge, P., 2010, A&A, 510, 25 Google Scholar
Silva-Valio, A. & Lanza, A. F. 2011, A&A, 529, 36 Google Scholar
Valio, A., 2013, Astronomical Society of the Pacific Conference Series, 472, 239 Google Scholar
Valio, A., Estrela, R., Netto, Y., Bravo, J. P., & de Medeiros, J. R., 2017, ApJ, 835, 294 Google Scholar