Flux and Polarization Spectra of Extrasolar Planets

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Flux and Polarization Spectra of Extrasolar
Planets
Lynette Cook
Daphne Stam
University of Amsterdam
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Characteristics of known extrasolar planets
i 0o
i90o
?
?
?
?
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Radial velocity amplitudes of the Sun due to
Solar System planets
Jupiter K ? 10 m/s T 4331 days Saturn
K ? 3 m/s T 10767 days Earth
K ? 0.1 m/s T 365 days
1995 accuracy 10 m/s Current accuracy 3 m/s
Future accuracy 1 m/s
Wanted for planet detection Direct observations
of planets!
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What do extrasolar planets look like?
?
Wanted for planet characterization Direct
observations of planets!
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Direct observations of extrasolar planets
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Reflected starlight versus thermal radiation
direct starlight
109
105
reflected starlight
thermal radiation
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Instruments for direct detection
Darwin - ESA - Infrared Space
Interferometer - Finding characterizing
terrestrial planets - Status in development -
Launch after 2014
CHEOPS - ESO - VLT Planetfinder - Finding
characterizing Jovian planets - Status Phase A
study (until October 2004) - Installation after
2008


CHaracterizing Exoplanets by Opto-infrared
Polarimetry and Spectroscopy
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CHEOPS direct detection techniques

• Adaptive optics
• Differential imaging

after
before
Liu et al., (2002)
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Differential imaging Numerical simulations
Guiding and optimizing the instrument design
star
a
planet
observer
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Spectroscopy along a planetary orbit
For a clear model atmosphere with absorption by
CH4 across the I-band
i90o
i0o
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Polarimetry along a planetary orbit
For a clear model atmosphere with absorption by
CH4 across the I-band
i0o
i90o
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Summary

• Extrasolar planets give information on planet
  formation, planetary atmospheres, planetary
  habitability, etc...

• Direct detections of extrasolar planets are
  needed
• Finding small and long-period planets
• Characterization of planets

• With numerical simulations, we can
• Aid the development optimization of detectors
• Analyze (future) direct observations