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SPHERE – the high contrast challenge. Markus Kasper, ESO. 1. Outline. SPHERE project history The mission The concept Demonstrations Now and soon. From the start…. 2 Phase A studies led by MPIA and LAOG: 2003 –2004. Phase A review Dec 2004
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SPHERE – the high contrast challenge Markus Kasper, ESO 1
Outline SPHERE project history The mission The concept Demonstrations Now and soon
From the start… 2 Phase A studies led by MPIA and LAOG: 2003 –2004 Phase A review Dec 2004 Major Merger: 2005 – 2006 (consortium agreement issue 1, Dec 2006)
SPHERE project structure • VLT 2nd generation instrument for Exoplanets • Consortium: LAOG, LAM, LESIA, LUAN, MPIA, Padova University, Obs. Geneve, ETH Zuerich, ASTRON and ONERA • Passed FDR in Dec 2008, now in MAIT phase • Many critical components (DM+driver, WFS CCD, IR detectors, large common path optics) already in house • Commissioning and 1st light in summer 2011, in less than 2 years!!
Lagrange et al. 2009 Possible exoplanets, directly imaged GJ 758, Thalmann et al 2009 HR 8799, Marois et al 2008
Science objectives Stars - BDs Large Surveys BDs - Planets Radial Velocity HC & HAR Imaging Transits μ Lensing
SPHERE features High contrast detection capability Contrast Gain up to 5 mag wrt current instrumentation (10-6-10-7) Extreme AO (SR ~ 90% in H-band) Coronagraphy at small inner working angles: 0.1 – 3 Spectral Differential imaging (IRDIS, IFS) Polarimetric Differential imaging (ZIMPOL) Characterization Polarimetry (IRDIS, ZIMPOL) Medium resolution Long-Slit spectroscopy (R~500 in range 0.95 – 2.32 microns, IRDIS) Low resolution spectroscopy (R~50, IFS, IRDIS) Classical imaging at high Strehl ratios (IRDIS, ZIMPOL)
Beam control DM, TTs 40x40 SH-WFS in visible 1.2 KHz, RON < 1e- λ = 0.5 – 0.9 µm - FoV = 3.5” 0.95 – 1.65 µm FoV = 1.77” ALC, 4QPMs, Lyot, Slits IR –TT sensor 0.95 – 2.32 µm - FoV = 12.5’’ Nasmyth platform, static bench, Temperature control, cleanliness control Active vibration control Concept overview
CPI HWP2 De-rotator ITTM HWP1 PTTM Polar Cal DM NIR ADC VIS ADC DTTS VIS corono ZIMPOL WFS NIR corono DTTP IFS IRDIS SPHERE implementation
Spectral Differential Imaging (SDI) Lenzen paper NACO, Close et al. 2003
Angular Differential Imaging (ADI) NACO at Nasmyth of VLT (Alt-Az) -> pupil and field rotate at different speeds Standard: Rotate NACO to stabilize field PA New option: Rotate NACO to stabilize pupil (and diffraction pattern and quasi-static speckles)
Predicted Science Output MC simulations (MESS, Bonavita et al.) • Modeled planet population or extrapolated RV distribution • Model planet brightness (thermal, reflected, albedo, phase angle,…) • Match statistics with RV results Mordasini et al. (2009) Young stars (<5 108 yrs) Nearby stars (<20 pc)
Science objectives Stars - BDs Large Surveys BDs - Planets Radial Velocity HC & HAR Imaging Transits μ Lensing
XAO with HOT • Developed at ESO in collaboration with Arcetri and Durham Univ. • 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
XAO coronagraphy with HOT Martinez et al., submitted to A&AL Good agreement with SPHERE simulations
Toric mirrors • All toric finished • TM1&TM2 in specs • New TM3 started
ZIMPOL Mark Downing (ESO), Peter Steiner (ETH) and Charlotte installing eng.detector system
Project Schedule • started in May 2001 • Phase-A, Consortium selection, PDR… • December 2008: Final Design Review • Jan.-Dec. 2009: Procurement / Manufacturing • Oct. 2009 – June 2010: Sub-systems AIT • July 2010 – February 2011: Global system AIT • Feb.-March 2011: Preliminary Acceptance Europe • May-End 2011: Commissioning • Early 2012: Beginning of science operation