MACAO-VLTI Adaptive Optics

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MACAO-VLTI Adaptive Optics

• 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

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
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MACAO-VLTIHow it started Challenges

• 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 _at_ M8 location 5m above WFS !!! Decoupled
  structure

• 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

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MACAO-VLTIMilestones Requirements

• Design Reviews
• System Deliveries

• Strehl Ratio
• Piston from DM lt
• Residual Jitter lt 10 mas
• Off-axis guiding
• On-line diagnosis
• Chopping

V lt 9 50
V 14.5 35
V 15.5 10
Concept Des. Rev. Sept. 99
Prelim. Des. Rev. Oct. 00
Final Des. Rev. March 01
2.5 yr !
Tip-Tilt Boxes (2) Nov. 01
MACAO2 (UT2) Apr. 03
MACAO3 (UT3) Aug. 03
MACAO4 (UT4) Aug. 04
MACAO1 (UT1) Mar. 05
25 nm RMS Window 48 msec
125 nm RMS Window 290 msec
2 mm PV Window 10 min
Allowed VLTI to combine UT2-UT3 using tilt
corrected beams (STRAP-M2)
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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 _at_ 420 Hz, (bandwidth 35 Hz)
• PowerPC 400 MHz Real Time Computer
• WaveFrontSensor detector APD coupled with Opt.
  Fibers
• Modular approach (4 VLTISINFONI/CRIRESspares)
• X-Y Table allows reference source selection
  off-axis
• (Strap quadrant detector tip-tilt sensor) TCCD
• Electronics VLTI-RTC-IC LCUs, XYTab., DM
  Amplifiers, APD Racks,
• High Level Eng. GUI Observing Software

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MACAO-VLTI Deformable Mirror Wavefront 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
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MACAO-VLTI WaveFront Sensor APD Cabinet
Beam Switching Device
(STRAP) TCCD
T-mount on XY table
APD Cabinet
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MACAO-VLTI Fiber Bundle
Heptagon Micro-Lens
Microfab Micro-Lens
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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

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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
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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

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MACAO-VLTI Paranal
Installation

• Five (5) comm. (inclu. TTB) from Dec.01 to
  Mar.05
• Required gt140 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!
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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
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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 shapeCapa. 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.

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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
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MACAO-VLTI Performance Results on UT2
HIC59206 V10Sep. 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.
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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 (f3) Smallest features 0.067
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MACAO-VLTI Results on UT3Interferometry
Calibrator fringes HD20356 with 2 MACAOs on
UT2-UT3 November 03
1st fringes with 2 MACAOs 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.
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MACAO-VLTI Results UT4
Tilt Correction
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MACAO-VLTI PerformanceStrehl Rogue Gallery
mv11.5 Seeing0.8 Sr(K)57 texp. 0.2s
mv8-9 Seeing0.5 Sr(K)63 texp. 0.2s
BEST Mv9.87 Seeing0.8 Sr(K)65
texp. 64s
mv15.5 Seeing0.6 Sr(K)26
texp. 0.5s FWHM 89mas
mv14.5 Seeing0.6 Sr(K)45
texp.0.5s FWHM 66 mas
mv16 Seeing0.55 Sr(K)26 texp.0.2s
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MACAO-VLTI PerformanceStrehl 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
  (April03 lower limit cause seeing gt spec.)
• Black squares Sky data on UT3 (August03)
• Red dash-dot line open loop strehl

• Strehl ratio versus guide star magnitude

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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
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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 EPROMs
• 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
  SMAAnti-Windup
• UT Vibrations implementation of VTK algorithm

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MACAO-VLTI Conclusions

• 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

• Delivery of systems on schedule
• All functionalities operational and tested in
  telescope environment
• Strehl Ratio Performance above spec. S60 bright
  sources (seeing 0.8) S25 V15.5 (seeing 0.6)
• Residual tip-tilt 5-9 mas for bright sources
• Similar performance on all UTs (homogeneous
  systems)
• Automatic acquisition through VLTI ISS templates
• Perf. Tested at Coude focus (not including delay
  lines)

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MACAO-VLTI Team