1 CANARY CANARY Laser Guide Star Laser Guide Star Multi-Object Adaptive Optics Multi-Object Adaptive Optics (LGS MOAO) (LGS MOAO) E-ELT PATHFINDER E-ELT PATHFINDER ON-SKY ON-SKY DEMONSTRATOR DEMONSTRATOR FOR EAGLE FOR EAGLE Richard Richard Myers Myers Durham Durham University University Royal Astronomical Socie
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1 CANARY Laser Guide Star Multi-Object Adaptive Optics (LGS MOAO) E-ELT PATHFINDER ON-SKY DEMONSTRATOR FOR EAGLE Richard Myers Durham University Royal.
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1
CANARYCANARY
Laser Guide Star Laser Guide Star Multi-Object Adaptive OpticsMulti-Object Adaptive Optics (LGS (LGS
MOAO)MOAO)E-ELT PATHFINDERE-ELT PATHFINDER
ON-SKYON-SKYDEMONSTRATORDEMONSTRATOR
FOR EAGLEFOR EAGLERichard MyersRichard MyersDurham UniversityDurham University
Principles of CANARY Principles of CANARY demonstratordemonstrator Rayleigh LGSRayleigh LGS Role of WHTRole of WHT Demonstration stages and Demonstration stages and
timescalestimescales Risk mitigationRisk mitigation Current statusCurrent status
Funding statusFunding status
Why “CANARY”?
Falcon: 8m MOAO (study)EAGLE: 42m MOAO
CANARY: MOAO demo on 4.2m WHT on La Palma, Canary Islands
9 May 2008 3 RAS
CANARY ConsortiumCANARY Consortium
Overlaps with EAGLE AO design team and SESAME team
Observatoire de Paris LESIADurham University Isaac Newton Group
Laboratoire d’Astrophysiquede Marseille
UK Astronomy TechnologyCentre
Fanny Chemla, Eric Gendron, Zoltàn Hubert, Aglaé Kellerer, Michel Marteaud, Gérard Rousset, Fabrice Vidal, Ali Basden, Sofia Dimoudi, Nigel Dipper, Colin Dunlop, Deli Geng, Andres Gueselaga, Dani Guzman, Mark Harrison, Tim Morris, Richard Myers, James Osborn, Chris Saunter, Gordon Talbot, Laura Young, Eddy Younger, Don Carlos Abrahams, René Rutten, Thierry Fusco, David Henry, Andy Longmore, Brice Leroux
EAGLE MOAO requirementsEAGLE MOAO requirements and baseline and baseline
implementationimplementation NIR Multi-Integral Field Unit (IFU) for 42m E-ELTNIR Multi-Integral Field Unit (IFU) for 42m E-ELT Wide IFU patrol field ≥ 5 arcmin with ≥ 20 such Wide IFU patrol field ≥ 5 arcmin with ≥ 20 such
IFUsIFUs ≥ ≥ 30% energy in 0.075 arcsec spatial element in H-30% energy in 0.075 arcsec spatial element in H-
bandband
Multiple LGS (≥ 6), multiple NGS (≥ 3)Multiple LGS (≥ 6), multiple NGS (≥ 3) Closed loop control of M4 telescope adaptive mirrorClosed loop control of M4 telescope adaptive mirror Open loop control of high order (≥ 100x100 Open loop control of high order (≥ 100x100
actuator) Deformable Mirror (DM) in each IFU actuator) Deformable Mirror (DM) in each IFU channelchannel
9 May 2008 6 RAS
Technical challenge and Technical challenge and proposed mitigationproposed mitigation
Open loop control of Open loop control of high order DMshigh order DMs calibrationcalibration
ELT LGSELT LGS Spot elongationSpot elongation High accuracy wide field High accuracy wide field
tomographytomography
Real-time control Real-time control (RTC)(RTC) AlgorithmsAlgorithms Scale of implementationScale of implementation
Key technology: RAYLEIGH LGS (RLGS)Key technology: RAYLEIGH LGS (RLGS) (e.g., SOR, WHT, MMT, SOAR, LBT LGS study)(e.g., SOR, WHT, MMT, SOAR, LBT LGS study) These use pulsed lasers with temporal WFS range gatingThese use pulsed lasers with temporal WFS range gating
to select LGS height and extension (range gate depth)to select LGS height and extension (range gate depth) The Rayleigh LGS Altitude and extension are The Rayleigh LGS Altitude and extension are programmableprogrammable They can emulate the spot elongation & cone-effect geometry of aThey can emulate the spot elongation & cone-effect geometry of a
SODIUM LGS on a MUCH LARGER telescopeSODIUM LGS on a MUCH LARGER telescope
SO:SO: 85 km sodium LGS85 km sodium LGS → → 8.5km Rayleigh LGS8.5km Rayleigh LGS 10km sodium layer10km sodium layer → → 1km range gate depth1km range gate depth 42m E-ELT42m E-ELT → → 4.2m WHT4.2m WHT
In principle: can emulateIn principle: can emulate sodium density evolution toosodium density evolution too
9 May 2008 9 RAS
However…However… BUT:BUT:
This scaling is not perfect This scaling is not perfect Atmosphere and wavelength are not scaledAtmosphere and wavelength are not scaled There will be additional uncorrected turbulence in There will be additional uncorrected turbulence in
demo compared to ELTdemo compared to ELT Need to reduce LGS separation to emulate ELT meta-Need to reduce LGS separation to emulate ELT meta-
pupil overlap at a given altitudepupil overlap at a given altitude
SO NEED:SO NEED: Concurrent Natural Guide Star (NGS) tomographyConcurrent Natural Guide Star (NGS) tomography Record corrected Record corrected wavefrontwavefront (truth sensor) as well (truth sensor) as well
as the near-IR image (Point Spread Function)as the near-IR image (Point Spread Function) To check that To check that currentcurrent MOAO correction is as predicted MOAO correction is as predicted
for for currentcurrent atmosphere atmosphere
9 May 2008 10 RAS
William Herschel William Herschel TelescopeTelescope
4.2m Alt-Az, La Palma4.2m Alt-Az, La Palma Operational Rayleigh LGS: Operational Rayleigh LGS: GLASGLAS
Grond-laag Laser Adaptieve optiek Systeem (Ground-layer Laser AO System) 18 W 515nm18 W 515nm Launch SystemLaunch System
No fly zoneNo fly zone Launch permissionLaunch permission Traffic ControlTraffic Control
MK cloneMK clone MASS/DIMM 20m from WHTMASS/DIMM 20m from WHT
SCIDAR 340m from WHTSCIDAR 340m from WHT
9 May 2008 11 RAS
GLAS WHT LGS GLAS WHT LGS FacilityFacility
ING - Astron - ING - Astron - DurhamDurham
Variation of closed-loop (●) and open-loop (○) Gaussian fit FWHM versus angular distance from centre of field for a 20s J-band image. Turbulence profile approx 50% at ground, 15% at 4km, and 35% at 16km. LGS altitude of 15km.
NAOMI AO System: UKATC-Durham-INGINGRiD imager: INGOASIS IFU: Lyon
9 May 2008 12 RAS
GLAS Software DescriptionGLAS Software Description
CANARY Demo StagesCANARY Demo Stages Phase A 2010Phase A 2010
3 3 ×× Natural Guide Stars (in 3’ field) open loop Natural Guide Stars (in 3’ field) open loop control of low order (8 control of low order (8 ×× 8 actuator) Deformable 8 actuator) Deformable Mirror (DM)Mirror (DM)
Natural Guide Star Truth Wavefront Sensor, Near-Natural Guide Star Truth Wavefront Sensor, Near-IR imagerIR imager
Phase B 2011Phase B 2011 Add 4 Add 4 × LGS open loop control of low order DM× LGS open loop control of low order DM Concurrent NGS tomography maintainedConcurrent NGS tomography maintained
Phase C 2012Phase C 2012 Closed loop LGS/NGS control of low-order DMClosed loop LGS/NGS control of low-order DM Open loop control of high-order DM (up to 32 Open loop control of high-order DM (up to 32 × 32 × 32
Proof of concept trial Proof of concept trial currently being integrated currently being integrated in Durhamin Durham
RTCRTC First version based on working PC-based systemFirst version based on working PC-based system Contract with ONERA/ShaktiwareContract with ONERA/Shaktiware
On-site component tests October 2008On-site component tests October 2008 LGS asterism test: Diffractive Optical Element LGS asterism test: Diffractive Optical Element
(Herriot-Watt)(Herriot-Watt) Gated CCD test on-skyGated CCD test on-sky Test Figure Sensor in WHT environmentTest Figure Sensor in WHT environment
9 May 2008 21 RAS
Current Current StatusStatus NGS main path opto-NGS main path opto-
using EAGLE design codesusing EAGLE design codes ONERA/DurhamONERA/Durham
Design Reviews June 2008Design Reviews June 2008 Phase A PDR, B/C CoDRPhase A PDR, B/C CoDR
RTC first contract June 2008RTC first contract June 2008
Phase A Space EnvelopeAt WHT Nasmyth
Phase B Optics
9 May 2008 22 RAS
PHASE B
9 May 2008 23 RAS
Phase C
9 May 2008 24 RAS
9 May 2008 25 RAS
9 May 2008 26 RAS
Funding StatusFunding Status UK (STFC)UK (STFC) France (various)France (various) EU FP7 Preparatory EU FP7 Preparatory
FundFund
EU OPTICON JRA-1 – appliedEU OPTICON JRA-1 – applied ESO-ledESO-led Includes additional WHT nightsIncludes additional WHT nights
Further STFC support for final phase - appliedFurther STFC support for final phase - applied Further French funding proposals - to be madeFurther French funding proposals - to be made