1 corot highlights annie baglin and eric michel observatoire de paris and all the corot team and all...

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CoRoT HighlightsCoRoT Highlights

Annie Baglin and Eric Michel Annie Baglin and Eric Michel

Observatoire de Paris Observatoire de Paris

and all the CoRoT Teamand all the CoRoT Team

* The Mission* The Mission

* Seismology* Seismology

* Stellar Rotation and Activity* Stellar Rotation and Activity

* Exoplanets* Exoplanets

Time Domain Time Domain StellarAstrophysicsStellarAstrophysics

2 major Scientific

Programmes

Same technical specifications

* Very high accuracy (1000 times better)

* Very long duration of observation of the same star ~150 days

* Very high duty cycle (> 90 %)

A « SMALL » space mission built and operated by CNES (France) with ESA, Austria, Belgium, Brazil, Germany and Spain

STSci Colloquium, Octpber 6th 2010

What is CoRoT ?

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Detect stellar oscillations like in the Sun to probe the stellar interior

Detect small planets through their transit

Stellar ultra high precision relative photometryStellar ultra high precision relative photometry

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The CoRoT Instrument The CoRoT Instrument

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Up to12 000 Faint stars R : 10 to 16

At 32 or 512 s

Telescope diameter 27cm Camera with 4 detectors

10 bright stars

V : 5.5 to 9.5 at 32s

March 8 2009

116 bright stars (+ 20 to 30)120 000 faint ones (+35 000)

STSci Colloquium, October 6th 2010

Launch December 27th 2006, 1378 days in orbitFunded till march 2013

Total cost= 160 M€

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The CoRoT product: light curvesThe CoRoT product: light curves


Time Domain Stellar Astrophysics

New field of research since ~ 2000

High precision, long duration, continuity- MOST and WIRE from space

- Ground based networks coordinated in longitude-- CoRoT, Kepler

-- ……

116 up to now + use of the exofield targets

The seismology targets

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9 Delta Scuti, 2 known gam Dor

16 B stars, 1Beta Ceph, 5 Be

12 giants (K,G,F)

22 A/early F stars ?2 Am, 7 Ap,

17 solar-like puls. cand.

(one observed twice)

7 O stars

1 SdB Few RR Lyr


Analysis of the light curves in the Fourier space

Rotation (days)

Oscillations (mn to h)

Granulation, super granulation…

Magnetic activity


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V= 7 V = 8

V= 6

White noise

granulation oscillationsAround 1 to 3 mHz

Almost regular spacing(as predicted)

Large separation Small separation

Detection of solar like oscillationsin Solar analogs

Michel et al. Science 2008Benomar et al. A&A 506, 2009


Difficulty: identification of the modes Spherical harmonics (n, l, m)Through a fit to an empirical spectrum

Echelle diagram

First interpretations


HD 49933 M= 1.13, Fe/H=-0.37, Prot=3.35 dCore ~8%, ZC 88%, 3 Gyr

dark = 0.2, Dturb = 50cm2/sMedium =0.2 Dturb =0light =0.1, Dturb =0

=0.0, Dturb =0

(Goupil et al 2010 A&A accepted)

Oscillations in the frequencies due to sharp features in the structure

(Mazumdar and Michel 2010, AN in press)

Extension of the core and mixing ?

Basis of the outer ZC and Helium ionisation zone

Seen also in a red giant !

HD 43587, F9V

HD 52265metal rich G0V star

Hosting a planetBallot et al. A&A submitted

In Cooler solar analogs

HD 46375, K0V, hosting a 3days planet ~135 Hz (Gaulme et al, A&A accepted)


Off the MS

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Blue l=0Red l=1

Green l=2Violet l=3

HD 49385HD 49933

Large amplitudesBrighter than the Sun

Vconv higherSame T

Life time of the modes longer

X

49385

X49933

Deheuvels et al. A&A accepted


a mixed mode

In Post MS only

What a mixed mode can tell ?


Hz

acobs = 748.6 ± 0.23 Hz

Models fitted to Teff, L/Lo, Z/X,

And

1.3 < M < 1.36 Mo

•The curvature of the ridge modified by the avoided crossing

* The frequency of the mixed mode (g type)

overshootingov < 0.15

But..presently unsuccessfulseveral modes involved

Some physics missing ?

Solar like oscillations in a Red Giant

Detection of the comb structure

l=0,1,2

= 3.47 Hz

= 0.65 ??

Mode lifetime14.7 days

Teff= 4750 K, L= 70 LoVery slow rotator

At very low frequency: ~ 30Hz

156 days

Carrier et al. A&A, 506 2009


A universal spectrum


Mosser et al. A&A accepted

De Ridder et al. Nature 2009

max

n,l / = n + l/2 +d 0,l

CoRoT

Kepler

Scaling law for ?

= A + B log

A Stellar Formation Rate indicator

* Statistics on max and Compared to models of synthetic populations

Miglio et al. A&A 2010


T1: constant formation rateT2: recent burst ≤ 1 Gyr

* Determination of Mass and Radius ( max )

Hot stars and solar like oscillations….

AAS Miami May 2010

Gravity modes?

Auto excitedBeta ceph

Solar like P modes

Deep interior, He ionisation zone, convective region

Belkacem et al. , Science, 2009

HD 461490 8.5 V

Teff= 35 000

NGC 2244Rosetta nebula

1,6 Myr

Red 30 MoGreen 34 Mo

Degroote et al.A&A accepted

HD 180642 B1 VTeff ~ 26 000 Log g= 3.8


Excitation mechanism?

The instability strip close to the MSDelta Scuti stars

130 stars with good fundamental parameters

80 % amplitudes [10-2 ,10-4]

Extremely rich spectrum

Many modes predicted unstable

Statistics ?

How to disentangle pulsations and granulation?

But……Rotation generally dominates….!

Beta Cephei pulsators

Briquet et al. A&A 2010 accepted

67 Frequencies


NO pusations detected, Only rotation (Papics et al. A&A submitted)

The Beta Cephei instability strip ?


HD 180642

67

NO

A Be star with a burst

HD 49330 V= 8.5 during 156 days

Enveloppe / pulsation Interaction ?

Huat et al. A&A 506,2009, Floquet et al. A&A 2010


An old hot B subdwarfVery faint, (V=14.9)

observed in the exoplanet field

24 frequencies (6 from the ground)g modes

Charpinet et al. A&A L, submitted


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The Rotation of the Sun in timeThe Rotation of the Sun in time

Extended program of spectroscopic observations

To obtain the Fundamental parameters

Dias de Nascimento eta., submitted


Rotation distribution of young starsRotation distribution of young stars

11275, FGK dwarfs

3000 confirmed periods

Not compatible with a constant star formation rateExcess of young stars (also seen in Xrays)

Affer et al. A&A 506, 2009

Constant star formation rate

Age from gyrochronology


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Activity IndexesActivity Indexes

= evolution time

H = activity index

(< 100 Hz)

Hulot et al.

~ P2 ?

Rossby number R= Prot/conv

H ~ R -1.5


(H , Tc)

400 stars of the exofield + 30 from the sismofield

~

1/P(rot)

Sun

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Spot modelingSpot modeling

HD 49933P rot: 3.35 daysSpot life time: 2.5 to 3.5 daysSurface of the spots 3%Inclination 55° in agreement with seismology


CP star HD 50773+spectropolarimetric observations

Mapping of surface inhomogeneities

A stellar cycle from seismology

HD 49933, F5V,

1.2 Mo, Rotation period 3.4 days

Observed twice for 400 days,

Modulation of seismic + activity indicators as in the Sun

around 120 days

Garcia et al., Science, Mathur


The CoRoT exoplanet programmeThe CoRoT exoplanet programme

From light curves to complete planet characterisation……

A long way to go…….

Per run

10 000 targets 300 candidates

50 selected for FU obs 2 to 4 planets !


15 +3 ?

CoRoT - 2CoRoT - 281 successive transits; Period: 1.742996 d; Radius: 1.465 RJ

Mass: 3.31 MJ; Rotation of the star 4.5 d

CoRoT - 6CoRoT - 615 successive transits; Period: 8.88 d; Rayon: 1.5 RJ

Mass: 3.3 MJ; Rotation of the star 6 d

Hot jupiters around very active stars


CoRoT- 3bCoRoT- 3b

34 transitsPeriod 4.26 dRadius: 1.01Mass: 21.66Rotation of the star ~ 4 d

Between stars and planets


CoRoT- 15bCoRoT- 15b

11 transitsPeriod 3 dRadius: 1.22Mass: 64

Deleuil et al. A&A 2008, 491, Bouchy et al. A&A accepted

A temperate gaseous planet

1.5 transit + WISE Photometry+ Harps Coralie spectroscopy..

Period 95 .27 days (145 days of observations)Transit duration 8.8 hours

Eccentricity 0.11G3V, not active, 0.9 Ms,

Rp= 1.1 Rjup, Mp= 0.84 Mj, Tsurf= 350K, H+ He+ 20mE rocks

CoRoT- 9CoRoT- 9


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The smallest oneThe smallest one

scale 1/100 !

~ 170 transitsPeriod: 0.85 j

P rot: 23 jR= 1.7 Rearth

CoRoT-7b


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Stellar activity and planet confirmationStellar activity and planet confirmation

CoRoT-7b A nightmare!

Strong noise due to stellar activity……Spot modeling confirms

0.85 days period exists, amplitude: 5m/sM= 4.5 M

Density ~ 5Silicates + water ?

second periodicity: 3.7 days, hot Neptune M= 9M

And a third one?

110 nights with HARPS:


Conclusion…..?

1- Stars can be better understood 1- Stars can be better understood Looking carefully at their time dependant propertiesLooking carefully at their time dependant properties

* Seismology techniques* Seismology techniques* Non coherent behaviors* Non coherent behaviors

They are very diverse, more complex than the Sun, They are very diverse, more complex than the Sun, and more complex than we thoughtand more complex than we thought

Models have to be revised and improvedModels have to be revised and improved

2- Planetary systems are also very diverse2- Planetary systems are also very diverseTransit observations, complemented by spectroscopyTransit observations, complemented by spectroscopy

-->> some insight on their physics (density)-->> some insight on their physics (density)Models have to be revised and improvedModels have to be revised and improved

The major difficulty for the detection and charcaterisation The major difficulty for the detection and charcaterisation of small planetsof small planets

Is the stellar variabilityIs the stellar variability

3- Stars and planetary systems have to be studied together3- Stars and planetary systems have to be studied togetherCoRoT, Kepler, and later PLATO…….CoRoT, Kepler, and later PLATO…….


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Thank you !

CoRoT data are public since december 2008Continuously pouring into the mission archive…

http://idoc-corot.ias.u-psud.fr

As soon as they are public at NStED

http://nsted.ipac.caltech.edu/NStED/docs/datasethelp/ETSS_CoRoT.html

Enjoy it !

The mission profile

december 27 2006 at 14:23:38 UT

1244 days in orbit

Intermediate size

mission

160 M$

600 kg

Polar orbit

at 896 km

0°

30°

60°

90°

120°

150°

180°

210°

240°

270°

300°

330°

0h2h4h6h8h10h12h14h16h18h20h22h

The CoRoT eyes


1 corot highlights annie baglin and eric michel observatoire de paris and all the corot team and all...

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