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EUCLID, the planet hunter
Jean-Philippe Beaulieu, Virginie Batista, Arnaud Ca ssan Christian Coutures & Jean-Baptiste Marquette
Institut d’Astrophysique de Paris
Pascal FouquéIRAP Toulouse
Eamonn Kerins & Matthew PennyUniv. Manchester
Jupiter ~ 1 dayEarth ~2 hours
How to detect a planet via microlensing
Jupiter ~ 1 dayEarth ~2 hours
Soleil
Radial velocities & Transit
Microlensing
How to detect a planet via microlensing
What we are doing these days…PLANET/uFUN
- Network of telescopes, round the clock observations, online analysis.
A fleet of 40+ telescopes on alertIncluding DOME C
Expected : 4-7 planets/Yr
The sun never rises on PLANET/uFUN !
SUN21.011.0 22.0 MM +
−∗ =
EARTH5.57.2p 5.5 MM +
−=
AU 6.2 5.16.0
+−=a
Beaulieu et al., 2006, Nature (PLANET, OGLE, MOA)
The first frozen super-Earth
A 9.8 ±0.7 M⊕ planet at 3.42 ±0.34 AU from a 0.81±0.08 Mo star
Muraki et al., 2011
October 2009
Detected with 40 cm tel
Follow up : -KECK- EPOXI (DEEP IMPACT)
- 25 planets to date, 14 published.
- Several planets in the cold Super Earth-Neptune regime (Beaulieu et al., 2006, Gould et al., 2006, Bennett et al. 2008, Sumi et al. 2010). Earth mass planets in the very near future if they are not extremely rare.
- Detection and measurement of the mass of a free- floating brown dwarf (Gould et al. 2009)
- Mass measurements can be accurate 10 % (Dong et al. 2009; Gaudi et al. 2008).
- Measurement of the individual planet masses, orbital radii, and inclination of the orbital plane for a 2-planet system, i.e., a Jupiter/Saturn analogue with both planets beyond the snow line
(Gaudi et al., 2008, Bennett et al. 2010).
- Saturns orbiting M-dwarfs beyond the snow line are substantially more common than Jupiters orbiting G-dwarfs
- Cold Neptunes and super-earths are even more common (Gould et al., 2010, Sumi et al. 2010)
Some recent results
Mid-term : 2012-2018
We will measure the frequency of :
- Giant planets beyond the snow line as a function of 3 variables: planet-host mass ratio, host mass, planet-host separation’s.
-Earth-mass planets beyond the snow line,
- Multi-giant-planet system
- Free-floating (i.e., ejected) giant planets.
Using existing facilities, automatic feedback of alerts to telescopes, and network of wide-field imagers (OGLE-IV, MOA-2, KMT) :
What is microlensing good for?
• Extending the exoplanet discovery space: capable of finding low-mass planets beyond the snow line
• Understanding exoplanet architecture: microlensing is able to characterise multiple-planet analogues of our solar system
• Putting planet formation theories to the test: microlensing sensitivity is right where core-accretion models predict the bulk of planet formation takes place
Microlensing of an Earth mass planet
• If planetary Einstein Ring < source star disk: planetary microlensing effect is washed out (Bennett & Rhie 1996)
• For a typical bulge giant source star, the limiting mass is ~10 M⊕
• For a bulge, solar type main sequence star, the limiting mass is ~ 0.1 M⊕
Earth mass planet signal is washed out for giant source stars
To get small mass planets, we need small source sta rs !
Ground-based confusion, space-based resolution
• Main Sequence stars are not resolved from the ground• Systematic photometry errors for unresolved main sequence stars cannot
be overcome with deeper exposures (i.e. a large ground-based telescope).
Microlensing from space
High Resolution + large field + 24hr duty cycle
Astro-2010 Decadal Survey“”The Kepler satellite … should be capable of detecting Earth-size planets out to almost Earth-like orbits.”
“As microlensing is sensitive to planets of all masses having orbits larger than about half of Earth’s, WFIRST would be able to complement and complete the statistical task underway with Kepler, resulting in an unbiased survey of the properties of distant planetary systems.”
Already in EUCLID yellow/red books
Besançon model
Microlensing simulator3 fields, 270 sec per pointing,
5x2 months observing
Penny, Kerins, Rattenbury, Beaulieu, Robin, 2012, MNRAS in prepPhD Matthew Penny
EUCLID microlensing
Simulated images of galactic Bulge
EUCLID will detect Mars mass planets
EUCLID planet catch with 5x2 months
Measuring the planet mass function
Microlensing program on board the EUCLID Dark Universe Probe
• Currently in additionnal science
• EUCLID understood the excellent synergy cosmic shear/microlensing requirements
• EUCLID/ML complements parameter space probed by RV and KEPLER
• Full census on planets down to Mars mass, getting η⊕(Abundance of habitable Earth)
• Getting free floating planets down to the mass of Earth
• From frozen to snow line to habitable planets
Penny, Kerins, Rattenbury, Beaulieu, Robin MNRAS paper, early 2012 release
Join now the club of happy few doing double precision
cosmology !
Become a microlenser now !
Ω*= 0.0027± 0.0005 (Fukugita & Peebles 2004)mp/M*=0.0035 ± 0.0018 (Cumming et al. 2008)
Ωplanets~10-5