Short-period Stellar Activity Cycles with Kepler Photometry
- Autor(en)
- O. V. Arkhypov, Maxim L. Khodachenko, Helmut Lammer, Manuel Güdel, Theresa Rank-Lüftinger, Colin Johnstone
- Abstrakt
We study the short-periodic component of stellar activity with a cycle period of Pcyc\lt 103 days using the Kepler mission photometry of fast-rotating (1\lt P\lt 4 days) stars with spectra of M4V to F3V. Applying the originally developed two non-spectral methods, we measured the effective period of stellar cycles in 462 objects. The obtained results are in accordance with previous measurements by Vida et al. and do not seem to result from a beating effect. The performed measurements of Pcyc cluster in a specific branch that covers the previously unstudied region in the Saar & Brandenburg diagram and connects the branch of inactive stars with the area populated by super-active objects. It is shown that the formation of the discovered branch is due to the α-quenching effect, which saturates the magnetic dynamo and decreases the cycle periods with the increase of the inverted Rossby number. This finding is important in the context of the discussion on catastrophic quenching and other heuristic approximations of the nonlinear α-effect.
- Organisation(en)
- Institut für Astrophysik
- Externe Organisation(en)
- Österreichische Akademie der Wissenschaften (ÖAW)
- Journal
- The Astrophysical Journal
- Band
- 807
- Anzahl der Seiten
- 15
- ISSN
- 0004-637X
- DOI
- https://doi.org/10.1088/0004-637X/807/1/109
- Publikationsdatum
- 07-2015
- Peer-reviewed
- Ja
- ÖFOS 2012
- 103003 Astronomie, 103004 Astrophysik
- Schlagwörter
- ASJC Scopus Sachgebiete
- Astronomy and Astrophysics, Space and Planetary Science
- Link zum Portal
- https://ucrisportal.univie.ac.at/de/publications/shortperiod-stellar-activity-cycles-with-kepler-photometry(2a610a23-af78-41fc-9ac8-eb5f2dd4862a).html