Pathways, Barcelona, 16 Sep 2009 EPICS, exoplanet imaging with the E-ELT Raffaele G. Gratton, Markus Kasper (PI), Jean-Luc Beuzit, Christophe Verinaud, Emmanuel Aller-Carpentier, Pierre Baudoz, Anthony Boccaletti, Mariangela Bonavita, Kjetil Dohlen,, Norbert Hubin, Florian Kerber, Visa Korkiaskoski, Patrice Martinez, Patrick Rabou, Ronald Roelfsema, Hans Martin Schmid, Niranjan Thatte, Lars Venema, Natalia Yaitskova ESO, LAOG, LESIA, FIZEAU, INAF-Osservatorio Astronomico di Padova, ASTRON, ETH Zürich, University of Oxford, LAM, NOVA 1 1
Pathways, Barcelona, 16 Sep 2009 Outline Science goals Instrument and AO concept Science Output prediction 2
Pathways, Barcelona, 16 Sep 2009 Exoplanets observations Close to 400 Exoplanets detected, >80% by radial velocities, mostly gas giants, a dozen Neptunes and a handful of Super-Earths Constraints on Mass function, orbit distribution, metallicity Some spectral information from transiting planets Spectrum of HD b Richardson et al., Nature 445, HR 8799, Marois et al 2008Beta Pic, Lagrange et al 2009
Pathways, Barcelona, 16 Sep 2009 (Some) open issues 4 Planet formation (core accretion vs gravitational disk instability) Planet evolution (accretion shock vs spherical contraction / “hot start”) Orbit architecture (Where do planets form?, role of migration and scattering) Abundance of low-mass and rocky planets Giant planet atmospheres 4
Pathways, Barcelona, 16 Sep 2009 Object Class 1, young & self-lum Planet formation 5 in star forming regions or young associations Requirements: High spatial resolution of ~30 mas (3 AU at 100 pc, snow line for G-star ) Moderate contrast ~
Pathways, Barcelona, 16 Sep 2009 Object Class 2, within ~20 pc Orbit architecture, low-mass planet abundance 6 ~500 stars from Paranal ± 30 deg, ~60-70% M-dwarfs Requirements High contrasts ~10 -9 at 250 mas (Jupiter at 20pc) + spatial resolution ~10 -8 at 40 mas (Gl 581d,~8 M ) 6
Pathways, Barcelona, 16 Sep Object Class 3, already known ones Planet evolution and atmospheres discovered by RV, 8-m direct imaging (SPHERE, GPI) or astrometric methods (GAIA, PRIMA) SPHERE discovery space GAIA discovery space From ESO/ESA WG report 7
Pathways, Barcelona, 16 Sep 2009 Contrast requirements summary 8
Pathways, Barcelona, 16 Sep 2009 Concept 9 9
Pathways, Barcelona, 16 Sep 2009 Concept: Achieve very high contrast Highest contrast observations require multiple correction stages to correct for 1. Atmospheric turbulence 2. Diffraction Pattern 3. Quasi-static instrumental aberrations XAO Visible diffraction suppression Diff. Pol. IFS Coherence- based concept? XAO, S~90% Diffraction + static aberration correction Speckle Calibration, Differential Methods Contrast ~ Contrast ~ Contrast ~ x 1000 ! 10 NIR diffraction suppression
Pathways, Barcelona, 16 Sep 2009 XAO concept Main parameters (baseline) Serial SCAO, M4 / internal WFS, XAO XAO: roof PWS at 825 nm, 3 kHz 200x200 actuators (20 cm pupil spacing) Simulation by Visa Korkiakoski AO + coro Advanced RTC algorithms studied in parallel to EPICS phase-A
Pathways, Barcelona, 16 Sep 2009 High Order Testbench (HOT) Demonstrate XAO / high contrast concepts Developed at ESO in collaboration with Arcetri and Durham Univ. Turb. simulator, 32x32 DM, SHS, PWS, coronagraphy, NIR camera H-band Strehl ratios ~90% in 0.5 seeing (SPIE 2008, Esposito et al. & Aller-Carpentier et al. ) correcting 8-m aperture for ~600 modes Aller-Carpentier, proc. AO4ELT
Pathways, Barcelona, 16 Sep 2009 HOT: XAO with APL coronagraph 13 700K object next to K0 star Good agreement with SPHERE simulations Additional gain by quasi-static speckle calibration (SDI, ADI) Martinez et al., submitted to A&AL
Pathways, Barcelona, 16 Sep 2009 Residual PSF calibration From systematic PSF residuals ( ) to Spectral Deconvolution (Sparks&Ford, Thatte et al.), Trade-off: spectral bandwidth vs inner working angle, IFS (baseline Y-H) Polarimetric differential imaging for smallest separation, needs planet “feature” (e.g. CH 4 band, or polarization) EPOL ( nm) Coherence based methods (speckles interfere with Airy Pattern, a planet does not) Self-Coherent camera (Baudoz et al, Proc. AO4ELT) Angular Differential Imaging (ADI) All 14
Pathways, Barcelona, 16 Sep 2009 Example: Spectral Deconvolution 15 15
Pathways, Barcelona, 16 Sep 2009 Speckle chromaticity and Fresnel nm rms at 10x Talbot 20 nm rms in pupil plane SD needs “smooth” speckle spectrum -> near-pupil optics
Pathways, Barcelona, 16 Sep 2009 End-2-end analysis Apodizer only leads to improved final contrast APLC Apodizer
Pathways, Barcelona, 16 Sep 2009 Baseline Concept All optics near the pupil plane minimize amplitude errors and speckle irregular chromaticity
Pathways, Barcelona, 16 Sep 2009 Ph noise w/o spider data removal Ph noise with spider data removal G2 star, 3pc, 10h Flat Field Systematics G2 star, 20 pc, 10h Detection limits, incl. photon noise
Pathways, Barcelona, 16 Sep 2009 Detection rates, MC simulation 20 20
Pathways, Barcelona, 16 Sep 2009 Predicted Science Output MC simulations planet population with orbit and mass distribution from Mordasini et al. (2009) Model planet brightness (thermal, reflected, albedo, phase angle,…) Match statistics with RV results Contrast model Analytical AO model incl. realistic error budget Spectral deconvolution No diffraction or static WFE Y-H, 10% throughput, 4h obs 21
Pathways, Barcelona, 16 Sep 2009 Detection rates, nearby+young stars Contrast requirements 22 Simulations by M. Bonavita
Pathways, Barcelona, 16 Sep 2009 Predicted EPICS output 23 Target class # targets Self- luminous planets Giant planets Neptunes Rocky planets 1. Young stars 688~100(~100)DozensVery few (?) 2. Nearby stars 512Dozen~100DozensDozen 3. Stars w. planets >100Some>100>Dozen>2 23
Pathways, Barcelona, 16 Sep 2009 Summary EPICS is the NIR E-ELT instrument for Exoplanet research Phase-A to study concept, demonstrate feasibility by prototyping, provide feedback to E-ELT and come up with a development plan Conclusion of Phase-A early 2010 Exploits E-ELT capabilities (spatial resolution and collecting power) in order to greatly advance Exoplanet research (discovery and characterization) 24