1 / 29

δ Scuti and γ Dor stars in COROT

δ Scuti and γ Dor stars in COROT. Rafael Garrido IAA, Granada (Spain). Current ground based observations δ Scuti: 0.3 – 3 hours (p- and mixed modes) γ Doradus: 0.4 – several days (g-modes) both regimes? (Dupret et al. 2004 A&A 414, L17)

Download Presentation

δ Scuti and γ Dor stars in COROT

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. δ Scuti and γ Dor stars in COROT Rafael Garrido IAA, Granada (Spain) Corot-Week 8

  2. Current ground based observations δScuti: 0.3 – 3 hours (p- and mixed modes) γDoradus: 0.4 – several days (g-modes) both regimes? (Dupret et al. 2004 A&A 414, L17) and Solar like oscillations? (Samadi et al. 2002 A&A 395, 563) • Mode identification: Frequency differences: Sismo & Exo Frequency combinations: Sismo & Exo Colour information: Exo Frequency Ratio Method (γDor) : Sismo & Exo Corot-Week 8

  3. Current ground based observations FG Vir Breger et al. 2004 A&A 419, 695 Corot-Week 8

  4. Current ground based observations FG Vir Breger et al. 2004 A&A 419, 695 Corot-Week 8

  5. Current ground based observations FG Vir Breger et al. 2004 A&A 419, 695 Corot-Week 8

  6. Current ground based observations FG Vir Breger et al. 2004 A&A 419, 695 Corot-Week 8

  7. Current ground based observations FG Vir Breger et al. 2004 A&A 419, 695 Corot-Week 8

  8. Current ground based observations DFT (Daily Aliasing) Frequencies estimations: simultaneous n-fitting at step n Frequency errors: Rayleigh resolution (1/T) or non-linear fitting Amplitude and phase errors: least square fitting at fixed frequencies Corot-Week 8

  9. Schwanzerberg-Czerny 1991 MNRAS, 253, 198: Uncorrelated observations σ(F) = √6/π * (N/S) * (1/√Nt) * (1/T) S/N Signal to Noise ratio Nt Total number of observations T Time base Correlated observations σ(F)= √D * σ(F) D Correlation length (“post mortem”) Corot-Week 8

  10. Present ground based observations Amplitude and phases errors: Least squares at fixed frequencies Best errors values for ground based : 0.05 mmags and 0.5 degrees. Main results for δ Scuti: Amplitude and phase variations Corot-Week 8

  11. 4 CVn Breger, M. 2000, MNRAS 313, 129 Rodriguez et al. 1998, A&A 338, 905 28 And Amplitude variations Corot-Week 8

  12. Breger, M. 2000, MNRAS 313, 129 Garrido & Rodriguez 1996 MNRAS 281, 696 4 CVn Corot-Week 8

  13. Wavelets (Equally spaced data): Morlet Mexican hat Corot-Week 8

  14. Wavelets (Equally spaced data): Corot-Week 8

  15. Bispectra (Equally spaced data) non zero only when quadratic coupling exists ! Corot-Week 8

  16. SOHO: bispectrum modulus. Corot-Week 8

  17. Corot-Week 8

  18. Suárez et al. 2005, A&A Submitted Corot-Week 8 z

  19. Breger et al. 1999 A&A 341, 151 Frequency differences FG Vir Corot-Week 8

  20. δ Scuti StarsRed border 2.2 M0 2 M0 p7 1.8 M0 1.6 M0 p1 1.4 M0 a = 0.5 - l = 0 Grigahcene et al. 2005 A&A 434, 1055 Dupret et al. 2004 A&A 414, L17 Dupret et al. 2005 A&A 435, 927 Corot-Week 8

  21. δ Scuti StarsRed border 2.2 M0 p7 2 M0 1.8 M0 p1 1.6 M0 1.4 M0 a = 1 - l = 0 Grigahcene et al. 2005 A&A 434, 1055 Dupret et al. 2004 A&A 414, L17 Dupret et al. 2005 A&A 435, 927 Corot-Week 8

  22. δ Scuti StarsRed border p7 p1 2.2 M0 2 M0 p1 1.8 M0 1.6 M0 1.4 M0 a = 1.5 - l = 0 Grigahcene et al. 2005 A&A 434, 1055 Dupret et al. 2004 A&A 414, L17 Dupret et al. 2005 A&A 435, 927 Corot-Week 8

  23. δ Scuti StarsRed border fB p6 fR g7 a = 1.5 - l = 2 2.2 M0 2 M0 1.8 M0 1.6 M0 1.4 M0 Grigahcene et al. 2005 A&A 434, 1055 Dupret et al. 2004 A&A 414, L17 Dupret et al. 2005 A&A 435, 927 Corot-Week 8

  24. γ Doradus starsg- and p-unstable modes 1.5 M0 - l = 1 - a = 1.5 Grigahcene et al. 2005 A&A 434, 1055 Dupret et al. 2004 A&A 414, L17 Dupret et al. 2005 A&A 435, 927 Corot-Week 8

  25. γ Doradus starsInstability strip Grigahcene et al. 2005 A&A 434, 1055 Dupret et al. 2004 A&A 414, L17 Dupret et al. 2005 A&A 435, 927 Corot-Week 8

  26. γ Doradus starsFrequency ratio method Moya et al. 2005 A&A, 432, 189 Suarez et al. 2005 A&A submitted Corot-Week 8

  27. γ Doradus starsFrequency ratio method Moya et al. 2005 A&A, 432, 189 Suarez et al. 2005 A&A submitted Corot-Week 8

  28. Poretti et al.2003A&A 406, 203 Poretti et al. 2005 A. J. 129, 2461

  29. CONCLUSIONS COROT data: • Continuous data (no alias, techniques requiring equally spaced data, high Nyquist frequency for sismo data) • Exploration of the high frequency region (Solar like?) • Discovery of unique objects (δ Scuti + γDor + solar like?) • Amplitude, phase (and frequency?) changes • Mode identification (frequency differences, linear combinations, colours, FRM) Corot-Week 8

More Related