1. Thanks to Henrietta Swan Leavitt, Harvard CfA November 5th 2008 1 Hommage to Henrietta Leavitt from the CoRoT Team 1908 2008 Annie BAGLIN, Merième CHADID, Zoltan KOLLATH, Michel AUVERGNE

2. Thanks to Henrietta Swan Leavitt, Harvard CfA November 5th 2008 2 A stellar photometer in space * Ultra high relative photometry 100 to 1000 times more accurate than from ground Very long continuous durations More than 150 days Dedicated to time variability from minutes to months The CoRot product : Light curves For 679 days in orbit

3. Thanks to Henrietta Swan Leavitt, Harvard CfA November 5th 2008 3 The focal plane The focal plane * * * * * * * * * * 1.3 ° field of view Seismology field highly defocussed main target (≤ 6) 12000 targets sampling 8.5 min (32 s.) secondary targets (≤ 9) 10 targets sampling 1 s to 32s Exoplanet field On focus + bi-prism faint stars (11-16) Aperture photometry on selected targets to reduce the TM flow

4. Thanks to Henrietta Swan Leavitt, Harvard CfA November 5th 2008 4 Seismology Targets already observed 6 Delta Scuti, 2 known gam Dor 10 B stars, Beta Ceph, 3 Be 10 giants (G,F)‏ 14 A/early F stars ? 2 Am, 7 Ap, 9 solar-like puls. cand. (one observed twice)‏ The classical HR diagram and the known class of variables

5. Thanks to Henrietta Swan Leavitt, Harvard CfA November 5th 2008 5 Solar like stars 6th mag White noise granulation oscillations Eric Michel and The SWG Detection and measurement of oscillations and granulation in several stars First interpretations show the presence of unexpected mechanisms of mixing in the stellar core

6. Thanks to Henrietta Swan Leavitt, Harvard CfA November 5th 2008 6 The Instability Strip Cepheids RRLyrae Delta Scuti Delta Scutis in the seismology field high accuracy Large number of modes ? RR Lyrae Continuous, ampl variations Blasko effect Cepheids Low amplitudes Double modes Strange modes?

7. Thanks to Henrietta Swan Leavitt, Harvard CfA November 5th 2008 7 Delta scuti stars 2 days 3 days

8. Thanks to Henrietta Swan Leavitt, Harvard CfA November 5th 2008 8 In delta scuti stars A very rich spectrum Eric Michel and the SWG Ground based observations The zoom below shows for the delat scuti star a very rich signal absent in another target of the same magnitude This signal is real…..needs interpretation….not easy!

9. Thanks to Henrietta Swan Leavitt, Harvard CfA November 5th 2008 9 NGC2264 CCD E1 Seismology, variability in the exoplanet field *Data collected for the exoplanet search, R< 16, ~5500 stars per CCD Presently ~ 88 000 observed

10. Thanks to Henrietta Swan Leavitt, Harvard CfA November 5th 2008 10 Variables are everywhere 40% variables

11. Thanks to Henrietta Swan Leavitt, Harvard CfA November 5th 2008 11 Automatic classification 29 classes Being Improved ….. 4 first runs IRa01, SRc01, LRc01, LRa01 200 SPB 190 Beta Cephei 32  Dor 1230 Delta Scuti 8 RR Lyrae 10 classical cepheids, 2 double mode 5800 low amplitude Cepheids ? A lot of uncertianties New classes? Debosscher et al.,

12. Thanks to Henrietta Swan Leavitt, Harvard CfA November 5th 2008 12 RR Lyrae: RRab with Blashko effect 150 days M. Chadid et al.

13. Thanks to Henrietta Swan Leavitt, Harvard CfA November 5th 2008 13 The Blazhko frequency Blazhko frequency 0.0369 c/d (27.1003 d) and its harmonic 0.0746 c/d For the first time the Blazhko frequency is directly measured in the Fourier spectrum. The Blazhko effect reduces the amplitude by over 50%.

14. Thanks to Henrietta Swan Leavitt, Harvard CfA November 5th 2008 14 First detection of an overtone For the first time in a RR ab star, additional mode: at 4.0323 c/d and half of it: 2.0162 with harmonics up to 5 th harmonic. Ratio to the fundamental frequency is 0.7177. fundamental and first overtone double mode pulsator...

15. Thanks to Henrietta Swan Leavitt, Harvard CfA November 5th 2008 15 Classical Cepheids Rare objects but several (10) detections in the exo field Amplitude (mag) 0.1 Period (days) 30 Amplitude 0.5 Period 6

16. Thanks to Henrietta Swan Leavitt, Harvard CfA November 5th 2008 16 Smaller and smaller? Amplitude 0.035 Period 6 Amplitude 0.03 Period 1.6 Amplitude 0.02 Period 5 Amplitude 0.02 Period 1.2

17. Thanks to Henrietta Swan Leavitt, Harvard CfA November 5th 2008 17 Probably a binary….. Sometimes curious objects, be cautious The two very small repeating spikes in phase cast doubts on the pulsation nature of the variation Only a very small sampling can reveal that as they last oy 4 hours

18. Thanks to Henrietta Swan Leavitt, Harvard CfA November 5th 2008 18 Strange Cepheids in the CoRoT targets There seem to be CoRTt variables in the predicted domain of strange modes Ground base observation are in progress to obtain precise stellar parameters (Zoltan Kollath et al.)

19. Thanks to Henrietta Swan Leavitt, Harvard CfA November 5th 2008 19 A Double mode cepheid f1: 0.778 c/d F2: 0.971 c/d More candidates…. More candidates to come…..

20. Thanks to Henrietta Swan Leavitt, Harvard CfA November 5th 2008 20