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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)

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δ Scuti and γ Dor stars in COROT

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  1. δ Scuti and γ Dor stars in COROT Rafael Garrido IAA, Granada (Spain) 2nd CoRoT Brazil

  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 2nd CoRoT Brazil

  3. Current ground based observations FG Vir Breger et al. 2004 A&A 419, 695 2nd CoRoT Brazil

  4. Current ground based observations FG Vir Breger et al. 2004 A&A 419, 695 2nd CoRoT Brazil

  5. Current ground based observations FG Vir Breger et al. 2004 A&A 419, 695 2nd CoRoT Brazil

  6. Current ground based observations FG Vir Breger et al. 2004 A&A 419, 695 2nd CoRoT Brazil

  7. Current ground based observations FG Vir Breger et al. 2004 A&A 419, 695 2nd CoRoT Brazil

  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 2nd CoRoT Brazil

  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”) 2nd CoRoT Brazil

  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 2nd CoRoT Brazil

  11. 4 CVn Breger, M. 2000, MNRAS 313, 129 Rodriguez et al. 1998, A&A 338, 905 28 And Amplitude variations 2nd CoRoT Brazil

  12. Breger, M. 2000, MNRAS 313, 129 Garrido & Rodriguez 1996 MNRAS 281, 696 4 CVn 2nd CoRoT Brazil

  13. Wavelets (Equally spaced data): Morlet Mexican hat 2nd CoRoT Brazil

  14. Wavelets (Equally spaced data): 2nd CoRoT Brazil

  15. Bispectra (Equally spaced data) non zero only when quadratic coupling exists ! 2nd CoRoT Brazil

  16. SOHO: bispectrum modulus. 2nd CoRoT Brazil

  17. 2nd CoRoT Brazil

  18. Suárez et al. 2005, A&A Submitted 2nd CoRoT Brazil z

  19. Breger et al. 1999 A&A 341, 151 Frequency differences FG Vir 2nd CoRoT Brazil

  20. 2nd CoRoT Brazil

  21. 2nd CoRoT Brazil

  22. 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 2nd CoRoT Brazil

  23. 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 2nd CoRoT Brazil

  24. 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 2nd CoRoT Brazil

  25. 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 2nd CoRoT Brazil

  26. 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 2nd CoRoT Brazil

  27. 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 2nd CoRoT Brazil

  28. γ Doradus starsFrequency ratio method Moya et al. 2005 A&A, 432, 189 Suarez et al. 2005 A&A 443, 271 2nd CoRoT Brazil

  29. γ Doradus starsFrequency ratio method Moya et al. 2005 A&A, 432, 189 Suarez et al. 2005 A&A 443, 271 2nd CoRoT Brazil

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

  31. 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) 2nd CoRoT Brazil

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