1. P-type pulsators on the main sequence of HR Diagram Gyöngyi Kerekes COROT-day Budapest March, 2007

2. HRD δ Scuti β Cephei SPB γ Doradus

3. Comparison TypePeriod Amplitude (in magnitude) Spectral type β Cephei3-8 hours0.01-0.8B2-B5 δ Scuti1-3 hours0.03-0.9A0-F5

4. δ Scuti HD 170782 V mag = 7.81 Spectral type: A2 Outside of the instability strip, blue edge Reopens the problem of variability

5. Whitening 1 2 3456 1 23 4 5 6

6. Fitting

7. Frequencies of HD 170782 Frequency (cycle/day) Amplitude (magnitude) Phase Noise (S/N) 2.90.00810. 83 18.79 4. 1 0.00640.4 5 14.91 25. 5 0.003 1 0. 63 8.84 13.20.00260. 02 5.9 7.80.00 20 0. 33 4.2 Frequency (cycle/day) Amplitude (magnitude) Phase Noise (S/N) 2.90.00810. 83 18.79 4. 1 0.00640.4 5 14.91 25. 5 0.003 1 0. 63 8.84 13.20.00260. 02 5.9 7.80.00 20 0. 33 4.2

8. β Cephei stars Known since 1902 10-20 solar masses Main pulsation modes  radial But non-radial pulsations also detected Large fraction is multiperiodic Frequency spectrum is not too dense  modelling becomes possible Very interesting from astroseismologic point of view

9. β Cephei HD 180642 Main target of the first COROT long run V mag = 8.3 Spectral type: B 1.5

10. Whitening 1 2 3 4567 1 2 3 4 567

11. Fitting

12. Frequencies Frequency (cycle/day) Amplitude (magnitude) Phase Noise (S/N) 5.4 9 0.0370.8 3 36.015 0.430. 01 0 0.48 10. 659 9.970.0090. 12 8.804 0.350.0050.985.351 8.810.0050.545.524 16.880.0040.914.59 Frequency (cycle/day) Amplitude (magnitude) Phase Noise (S/N) 5.4 9 0.0370.8 3 36.015 0.430. 01 0 0.48 10. 659 9.970.0090. 12 8.804 0.350.0050.985.351 8.810.0050.545.524 16.880.0040.914.59

13. Conclusions Main obtained frequencies: Trends in light curves ↓ Further cleanings are required HD 170782 belongs to small amplitude δ Scuti s → maybe more modes are excited → COROT’s task to investigate if there are more modes δ Scuti HD 170782 25.5 13.2 7.8 β Cephei HD 180642 5.5 9.97 8.81 16.88

14. Thank you for your attention!