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EPICS, exoplanet imaging with the E-ELT Markus Kasper, Jean-Luc Beuzit, Christophe Verinaud, Emmanuel AllerCarpentier, Pierre Baudoz, Anthony Boccaletti, Mariangela Bonavita, Kjetil Dohlen, Raffaele G. Gratton, 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, Osservatorio Astronomico di Padova, ASTRON, ETH Zürich, University of Oxford, LAM, NOVA AO4ELT, Paris, 23 June 2009 1 Outline Science goals (6s) Instrument and AO concept (12s) Science Output prediction (4s) AO4ELT, Paris, 23 June 2009 2 Exoplanets observations early 2009 ~ 300 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 HR 8799, Marois et al 2008 Beta Pic, Lagrange et al 2009 Spectrum of HD 209458b AO4ELT, Paris, 23 June 2009 3 Richardson et al., Nature 445, 2007 (Some) open issues 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 AO4ELT, Paris, 23 June 2009 4 Object Class 1, young & self-lum Planet formation in star forming regions or young associations Requirements: • High spat. resolution of ~30 mas (3 AU at 100 pc, snow line for G-star ) • Moderate contrast ~10-6 AO4ELT, Paris, 23 June 2009 5 Object Class 2, within ~20 pc Orbit architecture, low-mass planet abundance ~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) AO4ELT, Paris, 23 June 2009 6 Object Class 3, already known ones Planet evolution and atmospheres discovered by RV, 8-m direct imaging (SPHERE, GPI) or astrometric methods (GAIA, PRIMA) From ESO/ESA WG report GAIA discovery space SPHERE discovery space AO4ELT, Paris, 23 June 2009 7 Contrast requirements summary AO4ELT, Paris, 23 June 2009 8 Concept AO4ELT, Paris, 23 June 2009 9 Concept: Achieve very high contrast Highest contrast observations require multiple correction stages to correct for 1. 2. 3. Atmospheric turbulence Diffraction Pattern Quasi-static instrumental aberrations Diff. Pol. Visible diffraction suppression XAO NIR diffraction suppression Coherencebased concept? IFS XAO, S~90% Diffraction + static aberration correction Contrast ~ 10-3-10-4 Contrast ~ 10-6 Speckle Calibration, Differential Methods Contrast ~ 10-9 x 1000 ! AO4ELT, Paris, 23 June 2009 10 XAO concept Main parameters (baseline) AO + coro Serial SCAO M4 / internal WFS, XAO XAO: roof PWS at 825 nm, 3 kHz 200x200 actuators (20 cm pupil spacing) RTC requirements: Efficient algorithms studied outside EPICS phase-A 1e-6 1e-7 Numerical simulation, see poster of Visa Korkiakoski AO4ELT, Paris, 23 June 2009 11 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 See poster of Aller-Carpentier 100 95 90 85 SR (%) 80 75 70 65 60 55 AO4ELT, Paris, 50 232 June 2009 4 6 8 Star magnitude 10 12 HOT: XAO with APL coronagraph 700K object next to K0 star • Good agreement with SPHERE simulations • Additional gain by quasi-static speckle calibration (SDI, ADI) AO4ELT, Paris, 23 June 2009 13 HOT speckle stability 0 + 6hrs AO4ELT, Paris, 23 June 2009 +30 hrs 14 Correction of quasi-static WFE incl. segments piston DM “cleans” its control area from speckles Need: measure static aberrations some nm level at science wavelength through residual turbulence (PD or Speckle Nulling) Standard WFE specs ok for most optics (near pupil) Concept to be demonstrated FP7 funded exp. (FFREE@LAOG and HOT) AO4ELT, Paris, 23 June 2009 15 HOT: Segments piston and correction of quasi-static WFE 0.3 0.25 0.2 0.15 0.1 0.05 HOT pupil with DM and segmentation AO4ELT, Paris, 23 June 2009 With segmentation Residual PSF calibration Getting from systematic PSF residuals (10-6-10-7) to 10-8-10-9 Spectral Devonvolution (Sparks&Ford, Thatte et al.), Trade-off: spectral bandwidth vs inner working angle, IFS (baseline Y-H) Multi-band spectral or polarimetric differential imaging for smallest separation, needs planet “feature” (e.g. CH4 band, or polarization) IFS and differential polarimeter (600-900 nm) Coherence based methods (speckles interfere with Airy Pattern, a planet does not) Self-Coherent camera (see talk by P. Baudoz) Angular Differential Imaging (ADI) All AO4ELT, Paris, 23 June 2009 17 Example: Spectral Deconvolution AO4ELT, Paris, 23 June 2009 18 Speckle chromaticity and Fresnel SD needs “smooth” speckle spectrum -> near-pupil optics 20 nm rms at 10x Talbot 20 nm rms in pupil plane AO4ELT, Paris, 23 June 2009 19 End-2-end analysis Apodizer only leads to improved final contrast APLC Apodizer AO4ELT, Paris, 23 June 2009 E-ELT WFE requirements Segment Segment alignment (PTT) figuring Segment high orders M2-5, f>50 cycles/pupil Roughness < 36 nm rms < 50 nm rms < 50 nm rms < 30 nm rms < 5 nm rms AO4ELT, Paris, 23 June 2009 Baseline Concept All optics near the pupil plane minimize amplitude errors and speckle irregular chromaticity AO4ELT, Paris, 23 June 2009 Detection rates, MC simulation AO4ELT, Paris, 23 June 2009 23 Predicted Science Output MC simulations planet population with orbit and mass distribution from e.g. Mordasini (2007) 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 AO4ELT, Paris, 23 June 2009 24 Detection rates, nearby+young stars Contrast requirements Mordasini et al. 2007 AO4ELT, Paris, 23 June 2009 25 Predicted EPICS output Target class # targets Selfluminous planets Giant planets Neptunes Rocky planets 1. Young stars 2. Nearby stars 3. Stars w. planets 688 ~100 (~100) Dozens 512 Dozen ~100 Dozens Very few (?) Dozen >100 Some >100 >Dozen >2 AO4ELT, Paris, 23 June 2009 26 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) AO4ELT, Paris, 23 June 2009 27 END AO4ELT, Paris, 23 June 2009 28