1 / 10

Travis Metcalfe & KASC

Asteroseismology of 16 Cyg A & B from Kepler observations. Travis Metcalfe & KASC.

belita
Télécharger la présentation

Travis Metcalfe & KASC

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Asteroseismology of 16 Cyg A & B from Kepler observations Travis Metcalfe & KASC Collaborators: Sarbani Basu, Isa Brandão, Bill Chaplin, Orlagh Creevey, Sebastien Deheuvels, Gülnur Doğan, Patrick Eggenberger, Christoffer Karoff, Andrea Miglio, Dennis Stello, Mutlu Yildiz et al. (KASC WG1)

  2. Sun in time Li, Pcyc Guinan & Engel (2009)

  3. Porb > 18,000 yr Hauser & Butler (1999) Binary orbit V~6, extremely saturated

  4. Exoplanet orbit Cochran et al. (1997)

  5. Chromospheric activity Hall et al. (2007)

  6. Solar-like oscillations tgran = 257 ± 6 sec tgran = 241 ± 8 sec

  7. Model-fitting results • Fit each star independently, frequencies and spectroscopy • Reproduce the same fit with several codes (for systematics) • Best models have same age and composition (not forced) • MA=1.11, MB=1.07, t=6.8±0.4 Gyr, Zi=0.02(4±2), Yi=0.2(5±1) Metcalfe et al. (in prep)

  8. Chaplin et al. (2011, Science) Asteroseismic Modeling Portal http://amp.ucar.edu/ • Stellar evolution tracks from ASTEC, pulsation analysis with ADIPLS • Parallel genetic algorithm optimizes globally, local analysis + SVD for errors • Stellar age from match to large separation, correct surface effects empirically 0.75 < M< 1.75 0.002 < Z< 0.05 0.22 < Y< 0.32 1.0 <a< 3.0 Metcalfe et al. (2009), Woitaszek et al. (2009)

  9. Future prospects • (Differential) rotation: very low magnetic activity levels make spot modeling a challenge, but longer data sets should resolve mode splitting. • Convection zone depth: oscillatory signatures in D2n from acoustic glitches (due to CZ and He II) should be detectable with ~1 year time series. • Long-term variations: extended time series will allow the detection of secular (and periodic) variations in the frequencies, amplitudes, etc.

  10. Thanks to the international sponsor of the Kepler Asteroseismic Science Consortium

More Related