Transcript Slide 1

AP summary
Corot Be star group
GEPI, Meudon: Hubert, Floquet, Martayan, Frémat, Neiner
Univ. Valencia: Fabregat, Gutiérrez-Soto, Suso
Brazil: Janot-Pacheco, Andrade, Daflon
in collaboration with the B stars group (Aerts et al.)
CW9, ESTEC, Dec 2005
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Search for faint Be stars in the exoplanet fields
- Spectroscopy with the VLT/Giraffe
- Hα and R photometry with the WFI/INT + Stromgren
photometry
- IR photometry with IRAC/Spitzer
 Program accepted for AO1
CW9, ESTEC, Dec 2005
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Spectroscopy with Giraffe
Hubert et al.
- with VLT/Giraffe multifiber spectrograph
- parts of first anticenter long run field
- study B stars to detect emission in Hα
 2 faint Be stars detected...
 see CW8 (Hubert et al.)
CW9, ESTEC, Dec 2005
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Optical photometry with the INT
Fabregat et al.
- with WFI/INT (La Palma) with Hα and Sloan R filters
detect emission line stars
- whole exoplanet field of the first long run towards the
galactic center done in August 2005 (8 pointings * 4
CCDs)
- more observations in December 2005 for the exoplanet
field of the first long run toward the galactic anticenter
CW9, ESTEC, Dec 2005
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Figure shows 1/32 of the whole field (1917 stars with R<16.5)
 we expect to detect ~300 emission line stars in the whole field
CW9, ESTEC, Dec 2005
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Stromgren photometry
Fabregat et al.
- Stromgren photometry of the whole field already obtained, but
not yet reduced
- allows to perform a photometric spectral classification of the
detected emission line stars
 detect Be stars (~30 for center field) among emission line
stars
Diagram without
reddening [m1]-[c1]
CW9, ESTEC, Dec 2005
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IR photometry with Spitzer
Neiner et al.
- photometry in 4 IR bands with Spitzer/IRAC
- half of first anticenter field observed in 2004
- ~30000 stars detected and identified in each band
- cross-correlation with 2MASS, DENIS and Corotsky
- analysis of SEDs to find OB stars with IR excess
 detection of 10 Be stars
(in anticenter field)
CW9, ESTEC, Dec 2005
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Typical Be star SED
Possible Be star
observed with Spitzer
2MASS
Be
Black-body B
B
IR excess
Spitzer colors
CW9, ESTEC, Dec 2005
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Faint Be stars discovered for Corot
Anticenter field:
- 2 Be stars with Giraffe
- 10 Be stars with Spitzer
- 4 Be stars with Calar Alto (see Fabregat et al., CW5)
- a few Be stars with the INT (to be observed in 2 weeks...)
Center field:
- ~30 Be stars in the center field with the INT
CW9, ESTEC, Dec 2005
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Program accepted for AO1
collaboration Be stars group and B stars group
Observed all faint Be stars (~40) + some B stars (~250) in the
center and anticenter fields
Search for signatures of rotational modulation and pulsations
Perform seismic modelling of the stellar interior structure
Statistical study to fine-tune the excitation mechanism in B
stars and calibrate evolutionary models
Study occurence of Be phenomenon and relation with
pulsations, magnetic field, rotation
Link between Be outbursts and pulsation beating
CW9, ESTEC, Dec 2005
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