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Other Contributors: L. Close, J. Brynnel , J. Farinato , E. Brunetto , S. Stroebele , R. Reiss, E. Marchetti , D. Bonaccini Calia T. Craven-Bartle, M. Comin , T. Phan Duc , Wallanders …. MACAO-VLTI Adaptive Optics.
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Other Contributors: • L. Close, • J. Brynnel, • J. Farinato, • E. Brunetto, • S. Stroebele, • R. Reiss, • E. Marchetti, • D. BonacciniCalia • T. Craven-Bartle, • M. Comin, • T. PhanDuc, • Wallanders • … MACAO-VLTI Adaptive Optics R. Arsenault, R. Donaldson, C. Dupuy, E. Fedrigo, M. Kasper, N. Hubin, B. Delabre, S. Oberti, J. Paufique, L. Ivanescu, S. Tordo, S. Rossi, A. Silber, J.-L. Lizon, P. Gigan, M. Quattri 20th AO ESO 27.11.09
MACAO-VLTI:How it started… Challenges… • Low cost - reliable – easy to operate AO system • Polyvalent: feed VLTI, CRIRES, SPIFFI… • Few curvature system in world (IoA Hawaii, CFHT) • Believers/Architects: F. Roddier, G. Monnet, F. Rigaut • AO Group restructure 1999 • Fast track !!! (thanks to team !) • (FDR-4th Macao: 4 yrs) • Low Maintenance - easy to operate • (automatic: guide str mag. & seeing LUT) • Understand Curvature system… • Detailed simulations & test in Europe • Piston Spec. • New for AO systems; no real time feedback; open loop process… • DM mech. decoupled from WFS • DM @ M8 location 5m above WFS !!! Decoupled structure
MACAO-VLTI:Milestones & Requirements • Design Reviews: • System Deliveries: • Strehl Ratio: • Piston from DM < : • Residual Jitter < 10 mas • Off-axis guiding • On-line diagnosis • Chopping 2.5 yr ! Allowed VLTI to combine UT2-UT3 using tilt corrected beams (STRAP-M2)
MACAO-VLTI: System Characteristics • 60 elements Curvature System (vibrating membrane, micro-lenses, Bimorph DM and Tip-Tilt mount) • 2.1 kHz drive membrane mirror • AO loop controlled @ 420 Hz, (bandwidth ~35 Hz) • PowerPC 400 MHz Real Time Computer • WaveFrontSensor detector: APD coupled with Opt. Fibers • Modular approach (4 VLTI+SINFONI/CRIRES+spares) • X-Y Table allows reference source selection off-axis • (Strap quadrant detector tip-tilt sensor+) TCCD • Electronics: VLTI-RTC-IC LCU’s, XYTab., DM Amplifiers, APD Racks, • High Level Eng. GUI + Observing Software
MACAO-VLTI: Deformable MirrorWavefront Corrector CILAS Bimorphe DM • +/- 400 Volt • 100 mm pupil (150mm full size) • 60 electrodes • 40 intra-pupil • 20 extra-pupil (tilt) • Up to 1.2” seeing Deformable Mirror Tip-Tilt mount
MACAO-VLTI: WaveFront Sensor & APD Cabinet Beam Switching Device (STRAP) TCCD T-mount on XY table APD Cabinet
MACAO-VLTI: Fiber Bundle Heptagon Micro-Lens Microfab Micro-Lens
MACAO-VLTI: Optics WFS Optics Functions • Membrane vibration for curvature sensing (2.1 kHz) • Beam collimation • Pupil enlargment (14 18 mm) • Pupil imaging on Lenslet • Pupil centering on Lenslet • Pupil de-rotation CRITICAL • Rotating prism axis • Gimball tilt
MACAO-VLTI: Industries Applied Physics Specialties, Ltd. 17 Prince Andrew PlaceDon Mills, Ontario M3C 2H2Canada DR. SCHÜTTEN GmbH Dr.-Ing. Rudolf Schütten (Geschäftsführer) Frauenfelderstr. 95 CH-9548 Matzingen Shaktiware
MACAO-VLTI: Lab Tests • Optical Table in Lab. 038 • Simulated f/47 Coude beam • Phase screens & turbulence generator • DM in optical beam • WFS mounted under opt. table • RASOIR IR test camera
MACAO-VLTI: Paranal Installation • Five (5) comm. (inclu. TTB) from Dec.’01 to Mar.05 • Required >140 man-day/comm, 20 k € /comm transport, 15 k € overtime • Shipment/comm: 10 crates, 3 tons, 15 m3, value 1.4 M€ • All together ~8 staff monopolized for 1.5 months • Preparation: Hand & power tools, handling tools, books, docum., laptops, soft … • Lots of constraints before scheduled dates (calibr., scien. op. etc.) • Paranal overloaded with operation Limited Paranal prep. before arrival; but outstanding response once there • Heavy toll on staff (assume 2wks off after comm. or “low-profile”); one wk – 10 days on sky about limit of exhaustion! • Data reduction & Comm. Report prep. and writing not evaluated yet (2-3 wk/staff ?!) + Documentation to provide… The Right stuff!
MACAO-VLTI: Components Location Azimuth Cabinet • HVA, TTM elec., capa. RO M8 Well • TTM, DM, Capa. FE, DM mask Coude Room • WFS box • IC/XY Cab. • RTC/VLTI Cab. • APD Cab. • Cooling Coude focus
MACAO-VLTI: Calibrations • Membrane Mirror Stroke Calibration • RoC vs Volt; FOV of WFS for given RoC and Tilt • Membrane Mirror Phaselag Calibration • Use tilt signal; for which phaselag curv =0; add 180º • Interaction Matrices Calibration • ~6 matrices for different RoC; interpolation to cover whole range • DM Flattening (close loop with low gains; re-iterate) • Influence Functions (Piston; laboratory) • DM shape+Capa. Sensor (OPD offset); DM non-linearity • See paper 5490-100 on Calibrations Oberti, Bonnet, Fedrigo et al. • See paper 5490-182 on Piston Ivanescu, Arsenault, Fedrigo et al.
MACAO-VLTI System Description Coude Room View Front: ITC rack, M9 tower, Macao on XY table Back: Elec. Cab, APD rack, FOB, M9 cooling, SCP (For system description see Arsenault et al., 2003, SPIE 4839, p.174) Test Bench & Turbulence Generator
MACAO-VLTI Performance:Results on UT2 HIC59206 V=10Sep. 0.120” Seeing 0.75” 5 x 5 arcsec2 K-band image of "Frosty Leo" obtained in 0.7 arcsec seeing. V~ 11, difficult AO target because 3 arcsec in size at visible wavelengths. The corrected image quality is about FWHM 0.1 arcsec. Open-loop Close-loop 90-second K-band exposure of the central 6 x 13 arcsec2 around the Galactic Center obtained by under average atmospheric conditions (0.8 arcsec seeing). Although the 14.6 magnitude guide star is located roughly 20 arcsec from the field center the present image has a point-source FWHM of about 0.115 arcsec.
MACAO-VLTI: Results UT3 Mars image taken in August 8th 2003 Some ~20 mosaic images in K band Reference source: Deimos WFS offsets (excellent “exercise” for MACAO-VLTI functionalities) (thanks to MKA & STO) Neptune H band image Planet disk used for guiding (f=3”) Smallest features ~0.067”
Calibrator fringes HD20356 with 2 MACAO’s on UT2-UT3 November ‘03 MACAO-VLTI: Results on UT3Interferometry 1st fringes with 2 MACAO’s on UT2-UT3 14.08.03 Flux injected in VINCI fibers (beam combiner) versus MACAO-VLTI main loop gain. Approximately 50 times more flux injected with MACAO than with tip-tilt correction alone.
MACAO-VLTI Performance:Strehl Rogue Gallery mv=11.5 Seeing=0.8” Sr(K)=57% texp.= 0.2s mv=8-9 Seeing=0.5” Sr(K)=63% texp.= 0.2s BEST Mv=9.87 Seeing=0.8” Sr(K)=65% texp.= 64s mv=14.5 Seeing=0.6” Sr(K)=45% texp.=0.5s FWHM= 66 mas mv=15.5 Seeing=0.6” Sr(K)=26% texp.= 0.5s FWHM= 89mas mv=16 Seeing=0.55” Sr(K)=26% texp.=0.2s
MACAO-VLTI Performance:Strehl versus V magnitude Legend: • Pink diamonds: VLTI specifications • Blue curve: Computer simulations • Red Curve: Test Bench (lab.) measurements • Brown dots (error bars): Sky data on UT2 (April’03; lower limit ‘cause seeing > spec.) • Black squares: Sky data on UT3 (August’03) • Red dash-dot line: open loop strehl • Strehl ratio versus guide star magnitude
MACAO-VLTI Performance: Piston-control freq. influence • Piston Removal: • a)Determine piston mode • b)Given act. V, calibrate piston over pupil • c)Apply piston corr. V for each V (350 Hz) • Non-Linear double iteration See paper 5490-182 Ivanescu et al. for details
MACAO-VLTI MACAO-VLTI Upgrades ITF • Electronics cabinets vibrations: move out end-2006 (in progress; Paranal Eng.) • Membrane mirror phaselag switch solved (noise on APDCM); upgrade of EPROM’s • RTC Anti-Windup • FINITO injection (ITF): • Delay Lines alignment + VCM use; procedure • Source centering on Fiber; dynamic modulation • Tunnel Seeing: IRIS (+actuator pre-instrument!?) • PSF “explosion”: implementation of SMA+Anti-Windup • UT Vibrations: implementation of VTK algorithm
MACAO-VLTI: Conclusions • Delivery of systems on schedule • All functionalities operational and tested in telescope environment • Strehl Ratio Performance above spec. S~60% bright sources (seeing 0.8”); S~25% V~15.5 (seeing 0.6”) • Residual tip-tilt 5-9 mas for bright sources • Similar performance on all UT’s (homogeneous systems) • Automatic acquisition through VLTI ISS templates • Perf. Tested at Coude focus (not including delay lines) • Milestones • TTB (STRAP) Dec. ’01 • First closed loop lab. Aug.’02 • First closed loop sky 18.04.03 • First fringes 14.08.03 • End project 2005