MULTIPLE OBJECT ADAPTIVE OPTICS Mixed NGS/LGS Tomography Tim Morris (Durham University, UK) and Eric Gendron, Alastair Basden, Olivier Martin, David Henry, Zoltan Hubert, Gaetano Sivo, Damien Gratadour, Fanny Chemla, Arnaud Sevin, Matthieu Cohen, Eddy Younger, Fabrice Vidal, James Osborn, Richard Wilson, Tim Butterley, Urban Bitenc, Dani Guzman, Javier de Cos Juez, Andrew Reeves, Nazim Bharmal, Henri-Francois Raynaud, Caroline Kulcsar, Jean-Marc Conan, Jean- Michel Huet, Denis Perret, Colin Dickson, David Atkinson, Tom Baillie, Andy Longmore, Stephen Todd, David Anderson, Colin Bradley, Olivier Lardiere, Gordon Talbot, Simon Morris, Richard Myers and Gerard Rousset

Overview MOAO instrumentation CANARY Status CANARY Results SCAO, GLAO, MOAO, LTAO Bench and on-sky CANARY development

MOAO instrumentation First on-sky open-loop AO systems used on-axis guide star to control a single on-axis DM ViLLaGeS 1 and VOLT 2 demonstrated open-loop AO on-sky in 2007 & 2008 respectively Proved that open-loop control of AO systems was feasible Laboratory test benches were developed that were capable of investigating wavefront tomography and control UCO/LAO tomographic AO testbench 3 at UCSC SESAME at the Observatoire de Paris Combining open-loop control with wavefront tomography gave rise to instrument concepts such as FALCON and EAGLE 1.Gavel et al, Proc. SPIE Vol. 6888, p (2008) 2.Andersen et al, Proc. SPIE Vol. 7015, p70150H (2008) 3.Ammons et al, Proc. SPIE Vol. 6272, p (2006)

RAVEN RAVEN is a 2-channel MOAO system being built for the Subaru telescope. Feeds existing slit-based spectrograph Uses 3 off-axis NGS within a 3.5’ FOV 15 th magnitude NGS goal Can also use Subaru’s on- axis sodium LGS First light planned for May 2014

RAVEN Science camera images ( =  m) after 1s of turbulence history. NGS asterism radius = 40 arcsec. Currently assembled in the UVic AO lab and undergoing initial laboratory AO testing SCAO > MOAO > GLAO For more information see posters by: Olivier Lardière (RAVEN status) Kate Jackson (RAVEN tomography)

CANARY An open-loop tomographic AO demonstrator on the 4.2m William Herschel Telescope in La Palma Split into 3 phases of increasing complexity Phase A: NGS-only open-loop tomographic AO ( ) Phase B: Mixed NGS and LGS open-loop tomographic AO ( ) B1: Single LGS B2: Multiple LGS Phase C: Mixed NGS and LGS open-loop tomographic AO with a closed-loop GLAO/LTAO DM (2014+) 3’ DEROTATED TECHNICAL FIELD OF VIEW 3 OFF - AXIS OPEN - LOOP NGS UP TO M V ~ O N - AXIS CORRECTED SCIENCE / VERIFICATION PATH

CANARY so far... Phase B1 (3 NGS + 1 LGS) commissioned June 2012 Almost identical to RAVEN configuration (except on a 4m telescope with a Rayleigh LGS) Phase B2 (3 NGS + 4 LGS) first on-sky commissioning run finished yesterday morning Phase A (NGS only) completed 2010 Seeing-limited (NoAO) (SR=1%) GLAO (SR=9%) MOAO (SR=19.4%) SCAO (SR=23.8%) Asterism 47 and Phase A AO performance at 1.53μm

CANARY Phase B1 Single LGS that could be positioned anywhere within a ~1’ FOV In practice, LGS remained on-axis LGS altitude was fixed at 13.5km Provided photon return ‘safety margin’ 13.5km distant LGS WFS image 750m range gate ~4” per subaperture

CANARY Phase B2: 4LGS WFS 3 nights on-sky with the Phase B2 system from 23 rd to 25 th May 6 nights scheduled in July New for Phase B2: 4LGS WFS 128 x 128 pixel camera from MIT-LL/Scimeasure >1000:1 contrast ratio integrated shutter Pyramid-based asterism selection 21km central LGS focal distance 23” radius asterism 1.5km range gate depth 1.2” elongation A CQUISITION CAMERA P YRAMID F IELD S TOP L ENSLET LGS WFS

Rayleigh Fratricide Laser outputs more light at pulse rates > 10kHz Minimum laser pulse rate defines maximum altitude 10kHz allows a maximum LGS focal distance of 15000m Optical system defines what altitudes can be observed

CANARY Phase B2: Profiling New Stereo-SCIDAR turbulence profiler in addition to SLODAR and CANARY WFSs See talk by James Osborn on Wednesday 15:20 JKT

Profiling SLODAR Up to ~6km using existing binary targets Total turbulence strength Monitoring Stereo-SCIDAR High vertical resolution ~200m (at altitudes >0km) Wind velocities Relative turbulence strength (%) Altitude (m) CANARY Open-loop WFSs Up to 4 NGS and LGS for multi-baseline SLODAR profiling Takes telescope time

CANARY results Comprehensive analysis of Phase A/B results will be presented in this afternoon’s talk by Olivier Martin 1700) Results of the LQG on- sky reconstructor are going to be presented by Gaetano Sivo on Friday Here we present initial results from the Phase B2 run CANARY Phase B2 system at the WHT Nasmyth platform

NGS & LGS MOAO Three star test asterism (Ast T1) RA: , Dec: M b = 10.4, 11, layer tomographic reconstructor fitted NIR PSFs recorded at 1530nm 29.8” 56.6” 22.8” Relative turbulence strength (%) Altitude (m) GLAO SR = 9.9% SCAO SR = 21.5% NGS + LGS MOAO SR = 15.2%

NGS & LGS MOAO Strehl Ratio at 1.53μm Hour (UT) SCAO MOAO (4 LGS + 2 NGS) GLAO (4 LGS + 2 NGS) Results from single dataset taken switching between SCAO, combined NGS & LGS tomography and combined NGS & LGS GLAO

NGS & LGS MOAO Strehl Ratio at 1.53μm Atmospheric r 0 (m) A few caveats: CANARY is a low-order 7x7 system High frequency errors in the DM surface leave us with a large residual static error A few obvious points: SCAO > MOAO > GLAO GLAO still pretty good! A few less obvious points: CANARY data has shown WHT performance dominated by GL turbulence Quasi-static error term affecting MOAO results This term is difficult to calibrate and is partially due to varying field aberrations caused by the derotator

Open-loop LTAO CANARY LGS asterism diameter has been selected to optimise on-axis performance Optimal performance is found when LGS are positioned at ~ 1 pupil diameter at altitude No fundamental difference between CANARY 4 LGS MOAO configuration and optimal LTAO configuration Open-loop operation vs. Pseudo open-loop Asterism 32 2 Tip-Tilt, 4 LGS SCAO SR = 21.6% LTAO SR = 14.7%

On-sky tomography testing Have on-sky data for a wide variety of tomographic configurations: SCAO Mixed NGS and LGS MOAO 0 & 4 LGS, 1-3 NGS stars LGS-only MOAO (Open-loop LTAO) 4 LGS, 1-3 TT stars Mixed NGS and LGS GLAO (open-loop) 4 LGS, 1-3 NGS stars LGS only GLAO (open-loop) 4 LGS, 1-3 TT stars Have taken corrected datasets for both minimum variance and LQG reconstructors for most of these Bench validation using the CANARY telescope simulator is the first step

Bench tomography testing Turbulence generated using telescope simulator, 2 layers at 0 and 5200m 70% at ground, 30% alt. r 0 = 11 cm, L 0 ≈12 m Windspeed ≈ 6m/s NGS configured to simulate CANARY asterism A47 NGS NGS NGS Square LGS asterism 21.6’’ off-axis Altitude 17000m

SCAO 4LGS+3NGS 4LGS+2NGS 4LGS+1NGS 3LGS + 3NGS 2LGS+3NGS 1LGS+3NGS 4LGS+3TT 4LGS+2TT 4LGS+1TT 3NGS GLAO 4LGS+3NGS Strehl Ratio at 1.55μm Hour (UT)

CANARY: A Flexible Testbench CANARY doesn’t only demonstrate MOAO! Reconfigurable optical layout allows many other tests New WFSs LGS WFSing with controlled elongation Linux-based RTCS has been readily adapted as the project has progressed Many new centroiding techniques New reconstructors Several talks/presentations this week about techniques developed and tested/to-be tested on-sky using CANARY TopicWhoWhatWhen On-sky phase diversityDamien GratadourTalkToday 17:40 Open-loop tomographyOlivier MartinTalkToday 17:00 LQG reconstructionGaetano SivoTalkFriday 12:00 Real-time Control SystemsRichard MyersTalkFriday 14:20 On-sky CuRe-type reconstructors testsUrban BitencPoster Sodium LGS elongation studiesGerard RoussetPoster

Tomography with Artificial Neural Networks Using machine learning to generate a robust tomographic reconstructor Advantages: Includes non-linear effects difficult to model Single reconstructor optimal for all turbulence profiles Disadvantages: Requires a large amount of training data Training process can take a long time for large systems For CANARY: L&A: 1minute, ANN: 10 minutes Valid only for a given asterism Good for LGS systems!

ANN Tomography WFS x 3 Trained an ANN reconstructor using CANARY bench measurements Compared to L&A reconstructor trained on a 2-layer atmosphere (0km and 2.8km) Reconstructed on-axis WFS slopes whilst changing conjugate altitude of high layer

CANARY future Phase C1: LTAO (on-sky May/July 2014) Design review next week Reorganisation of the bench to place WFSs behind DM Additional figure sensor for pseudo open-loop operation Phase C2: E-ELT configuration MOAO (on-sky 2015) Closed-loop GLAO DM (existing low-order DM) Open-loop MOAO DM (high- order DM) High order figure sensor High order LGS WFSs

Photon return LGS photon return measured at Phase B1 on a single LGS Varying RGD makes this easy! Projected to 4 LGS Phase C1/2 Defines optimal LTAO error at Phase C1 Defines how many subapertures we can use at Phase C2

Beyond Phase C Funding has been secured for further on-sky investigations with CANARY: Focal plane NIR WFSing E-ELT scale LGS elongation WFS study Several ideas have been proposed for later phases: Open-loop MCAO demonstration LGS uplink tomography for tip-tilt determination Additional technology demonstrations planned: On-sky demonstration of AO-coupled integrated photonic spectrograph Always open to new collaborations that will benefit from an on-sky test…

Conclusions CANARY is now almost in its final configuration with a world record (?) 8 full frame rate, high-order wavefront sensors We have demonstrated mixed NGS and LGS open-loop tomography on-sky Additional results this afternoon! LGS MOAO works and can provide much better performance than LGS GLAO Closed-loop LTAO and high-order MOAO on-sky in 2014/15 repsectively

System Growth CANARY complexity has increased since initial testing phase in early 2009 Currently have 8 WFS’s, 25 reference sources and 288 WFS subapertures Number of WFSs Number of reference sources Number of WFS subapertures

AO4ELTs, Paris 2009CANARY: NGS/LGS MOAO DEMONSTRATORDurham Richard Myers, Gordon Talbot, Nigel Dipper, Deli Geng, Eddy Younger, Alastair Basden, Colin Dunlop, Nik Looker, Tim Butterley, Laura Young, Simon Blake, Sofia Dimoudi, Paul Clark, Nazim Bharmal, Richard Wilson, Harry Shepherd, James Osborn, Urban Bitenc, Andrew Reeves, Simon Morris Observatoire de Paris Zoltán Hubert, Gerard Rousset, Eric Gendron, Fabrice Vidal, Damien Gratadour, Aglae Kellerer, Michel Marteaud, Fanny Chemla, Phillipe Laporte, Jean-Michel Huet, Matthieu Brangier, Olivier Martin, Mathieu Cohen, Denis Perret, Arnaud Sevin, UKATC David Henry, Stephen Todd, Colin Dickson, Brian Stobie, David Atkinson, Tom Bailie, Martin Black, Andy Longmore ONERA Jean-Marc Conan, Thierry Fusco, Clelia Robert, Nicolas Vedrenne ING Jure Skvarc, Juerg Rey, Neil O’Mahoney, Tibor Agocs, Diego Cano, Don Carlos Abrams IOGS Caroline Kulscar, Henri-Francois Raynaud, Gaetano Sivo Others Andres Guesalaga (PUC Santiago), Dani Guzman (PUC Santiago), Javier de Cos Juez (University of Ovideo)  The CANARY project is supported via the following funding bodies STFC, UK E-ELT Design Study STFC, UK E-ELT Design Study EU FP7 Preparatory fund WP9000 EU FP7 Preparatory fund WP9000 ANR Maui, INSU, Observatoire de Paris ANR Maui, INSU, Observatoire de Paris FP7 OPTICON JRA1 FP7 OPTICON JRA1