Sounding stellar cycles with Kepler - II. Ground-based observations★

Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaperJournal articleResearchpeer-review

  • C. Karoff
  • Travis Scott Metcalfe
  • W. J. Chaplin, School of Physics and Astronomy, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
  • ,
  • S. Frandsen
  • F. Grundahl
  • H. Kjeldsen
  • J. Christensen-Dalsgaard
  • M. B. Nielsen, Stellar Astrophysics Centre, Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, DK-8000 Aarhus C, Denmark
  • ,
  • S. Frimann, Stellar Astrophysics Centre, Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, DK-8000 Aarhus C, Denmark
  • ,
  • A. O. Thygesen, Centrum für Astronomie der Universität Heidelberg, Landessternwarte, Königstuhl 12, D-69117 Heidelberg, Germany
  • ,
  • T. Arentoft, Denmark
  • T. M. Amby, Stellar Astrophysics Centre, Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, DK-8000 Aarhus C, Denmark
  • ,
  • S. G. Sousa, Centro de Astrofísica, Universidade do Porto, Rua das Estrelas, P-4150-762 Porto, Portugal
  • ,
  • D. L. Buzasi, College of Arts and Sciences, Florida Gulf Coast University, 10501 FGCU Boulevard South, Fort Myers, FL 33965-6565, USA
We have monitored 20 Sun-like stars in the Kepler field-of-view for excess flux with the Fibre-fed Echelle Spectrograph on the Nordic Optical Telescope since the launch of Kepler spacecraft in 2009. These 20 stars were selected based on their asteroseismic properties to sample the parameter space (effective temperature, surface gravity, activity level, etc.) around the Sun. Though the ultimate goal is to improve stellar dynamo models, we focus the present paper on the combination of space-based and ground-based observations that can be used to test the age-rotation-activity relations. In this paper we describe the considerations behind the selection of these 20 Sun-like stars and present an initial asteroseismic analysis, which includes stellar age estimates. We also describe the observations from the Nordic Optical Telescope and present mean values of measured excess fluxes. These measurements are combined with estimates of the rotation periods obtained from a simple analysis of the modulation in photometric observations from Kepler caused by starspots, and asteroseismic determinations of stellar ages, to test relations between age, rotation and activity.
Original languageEnglish
JournalRoyal Astronomical Society. Monthly Notices
Volume433
Issue4
Pages (from-to)3227-3238
Number of pages2
ISSN0035-8711
DOIs
Publication statusPublished - 1 Aug 2013

Bibliographical note

Erattum: MNRAS (January 11, 2015) 446 (2): 1139. doi: 10.1093/mnras/stu2114

    Research areas

  • Sun: activity, Sun: helioseismology, stars: activity, stars: oscillations

See relations at Aarhus University Citationformats

ID: 55518339