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Adaptive Optics for the E-ELT status review of Phase A & B activities. Norbert Hubin Adaptive Optics Department. The Adaptive E-ELT. Why? Increased collecting area Fainter sources Increased diameter Increased spatial resolution (with AO). Baseline Design 5 mirrors design
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Adaptive Optics for the E-ELTstatus review of Phase A & B activities Norbert Hubin Adaptive Optics Department
The Adaptive E-ELT Why? Increased collecting area Fainter sources Increased diameter Increased spatial resolution (with AO) • Baseline Design • 5 mirrors design • 42 meters diameter • cost 1000 M€ Phase “B” Design Study launched end 2006 - 3 years study
Few” IFU 6-8 LGSs in Ø 7.2’ Adaptive Optics Zoo GLAO-LGS LTAO: ATLAS MCAO:MAORY MOAO:EAGLE SCAO & XAO: EPICS GLAO-NGS
internal AO LTAO MCAO NGS CH35% 0”.1 px MOAO MCAO SH 30% XAO SH80% H-band H-band 2a H-band Multi-LGS 2b 1’ 1 800 mas GLAO 240 mas 8/100 mas 2b 400 mas E-ELT AO Modes Studied #1: Seeing-limited;1’: Improved seeing #2a: Luminosity-limited #2b: Diffraction-limited • 0”.8 s0 • 25 m L0 Combined Telescope–AO Systems–Instrument capability
1st level fast aO[always on] GLaO NGS #1: Seeing-limited 3 NGS GLAO [active optics + 10Hz TT ~few 100 low order aberrations incl. phase error propagation] all clear/safe nights; whole sky; 10’ field; all
Impact of Cn2 profile (5’ FOV) Difference between 25% best and 25% worst profiles @ Paranal Model 1: 46 % in first 500m, 0.6’’ seeing Model 2: 90% in first 500m , 0.6’’ seeing Model 3: 35% in first 500m, 1’’ seeing Model 4: 80% in first 500m , 1’’ seeing Largest impact of all parameters for GLAO
PSFs of GLAO Atm 1 K H J I GLAO seeing
PSFs of GLAO Atm 2 K H J I GLAO seeing
Limiting magnitude / Sky Coverage 5’ FOV Numbers being cross validated with ESO astronomers Sky coverage by P. La Penna Approximate magnitude per guide star
optical domain #1: Seeing-limited (fast aO) • Universe expansion cm/s VR over 20-year • Exo-planet VR detection cm/s VR over 2-year • IGM low- metallicity CODEX (coudé Lab) 0.37--0.69+m; ~1.2x105 ESO, Trieste & Brera, IAC, IoA, UniGe Light beam stabilization: T/T, focus, ...
reddish domain #1’: Improved Seeing (GLAO) • Large Scale Structure/galaxy evolutionhugemultiplexspectrometer OPTIMOS: wide Field visual MOS (fibre or slit-based)
Single Conjugate AO NGS 1st light diffraction limited AO? • #2b: on-axis diffraction-limited • SCAO-NGSs a la NACO(< 1’ field); variable PSF • Visible & IR Wavefront sensor for highly obscured region • 70-45% Strehl ratio in K; 80% EE in 75mas spaxel • 11 mas FWHM, low sky coverage<2% • Any instrument using AO at 1st light? even in degraded Sky Coverage performance • SIMPLE • HARMONI • MICADO • METIS
Telescope Adaptive Optics WFS adaptor Pupil steering mirror WFS arm preliminary optical design Collimator Detector WFS arms (contain WFS detectors) Lenslet array Reimaging lens Some instruments also contain WFS detectors : Deformable Mirror WFS adaptor Field steering mirror Zoom optics 1100 mm Instruments
#1’: Improved seeing • GLAO + 4 LGS [fast T/T+~5.103 modes]; 250 mas FWHM • or with 3 NGS [30-50% sky in K; laser-adverse nights] • no/light* cirrus; ~ all seeing; ~ full sky in J-H-K • 5’ field in K; ~40” at 600nm-limited sky coverage 1st level AO [mostly on] LGS-NGS GLAO also1ststeptoMCAO,MOAO&XAO
Number of LGSs for GLAO ? Old simulation conditions, so EE values should be scaled
One possible M4 Adaptive Mirror • 7k actuators WFE=113 nm rms (seeing 0.85” @ 0.5 μm • Full stroke of 80 μm • Mirror positioned with a hexapod May 12th, 2009 E-ELT Phase B Mid-term Review
Another possible M4 unit Shell machining • 6k actuators WFE=129 nm rms (seeing 0.85” @ 0.5 μm • Full stroke of 160 μm • Mirror positioned with a hexapod + Nasmyth switcher
A possible 2.6m M5 field stabilization Unit Mounting frame Backside with support elements and actuators
Laser Guide Star Concept: side launch • 40 cm Laser launch Telescope • Up to 2x20W laser unit each • Relay, diagnostic tools • Jitter, beam steering • Enclosed baffle? • LGS station access & servicing
Side launching fratricide effect(LGS beacons rotating with sky field) GLAO WFSs with 4LGSs MOAO WFSs with 6 LGSs
E-ELT launch telescope baseline VLT AOF 4 units being designed & built by TNO-TPD (NL) for VLT-AOF Diameter: 400mm Useful aperture: 300mm UnvignettedFov: 12’ Pointing precision: <0.1” Output Beam diameter 300 mm Beam magnification 20 WFE excluded focus: 50nm rms Focus WFE: <1 wave P-V at 589nm Throughput @ 589nm: T ≥ 95% Total max: <200kg Interface: TBD
Sodium Laser studies: AOF E-ELT? • 1st contract: PDR and Critical Technology Demonstrator development • Goal: to secure interfaces and critical technology (risk reduction) • 2 studies & 2 risk reduction studies funded by (ESO, OPTICON) & (Keck, TMT, GMT & AURA) • Fasortronic (USA) & TOPTICA (GER): both have demonstrated >20W • Feb.- Nov 2009 • Firm fixed price offer for 2nd contract at the end of 1st contract • 2ndcontract: FDR & Pre-Production Unit (2010) • Final Design Phase: 6 months (incl. long lead items procurement) • Pre-Production Unit MAIT: 12 months • After go-no go milestone 2nd contract: MAIT and delivery of 4 Laser Units • Laser Units MAIT and delivery: 17 months N. Hubin
Sodium Laser Requirements • CW or QCW laser • Return flux: 4-5 106 photons/m2/s per LGS at Nasmyth (Na column density: 4 1013 m-2) • Baseline specification • Emission wavelength: peak of the D2a line in the mesosphere (≈589 nm) • 25 W - line width = 50 MHz 10 MHz • Optional specification: making use of Sodium back-pumping! • 2 lines emitted: peak of D2a and D2b lines in the mesosphere • The frequency shift between the two lines shall be stable within 10 MHz • 18 W in the D2a line and 2 W in the D2b line • Linewidth between 40 MHz and 250 MHz (for both lines) • Laser beam quality (long term): M2 < 1.3 (goal 1.1)
2nd level AO [photon-starved] MOAO EAGLE & MAORY MCAO • Physics & mass assembly of galaxies to z~4.7 highest H-K energy concentration (30%) in 75 mas • Highest redshift galaxies at z>6 • highest patrol field (up to 10’ with MOAO) #2a: Luminosity-limited MOAO/6-8LGSs (5-10’ field) or MCAO/6LGSs (< 2’ field) Spaxel of 75 mas; 30% Ensquared Energy most sky; 75% seeing (K) / very good seeing (I) EAGLE 0.8-2.4 m 20+-IFS LAM, OPM, ONERA, UKATC, Durham
#2b: Diffraction-limited • 60% sky coverage & 50% seeing in K, Strehl(K)>40-50% • 15% sky & exceptional seeing in I • ATLAS/6LGSs(15-30”field) & MAORY/6LGSs (< 2’ field) 2nd level AO[maximal resolution] MCAO MAORY & LTAO ATLAS ΩCen MAD ‘06
#2b: Diffraction-Limited (MCAO/LTAO) ATLAS • resolved stellar population imaging1% photometric precision CMD in K-I • resolved stellar population spectroscopy good Strehl at 850 nm (Ca Triplet) • Z~2-5 L* galaxy imaging very low-noise science detector • SMBH spectroscopy at center of galaxies extremely low-noise science detector MICADO (SCAO 1st light?) 0.8-2.4 m D-L imager MPE, MPIA, USM, INAF, NOVA HARMONI (SCAO 1st light?) 0.8--2.4 m D-L single IFU Oxford, CRAL, DAMI. UKATC
2nd level AO [maximal Strehl] EPICS: XAO & high contrast • Exo-planet direct detection • critical internal stability • Debris disks #2b: Extreme contrast 25% seeing; zero field; 0.65 μm XAO/NGS [~3.104 modes]also ‘visible’ AO few 10-9 contrast so far EPICS 0.6-1.8 m diff. spectro/polarimeter ESO, LAOG, LESIA, FIZEAU Lab, LAM ONERA,Oxford,Padova,ETHZ,NOVA X-AO Apodizer Differential extraction
LTAO ATLAS & SCAO • Circumstellar dust chemistry • PaH spectrometry (high-sensitivity N detector) • Planet-forming dust emission Mid-IR AO (8-24 μm) M4-M5 provides ATLAS/SCAO NGS on 60% sky (0.9 Strehl) (IR WFS for highly obscured regions) ~ luminosity/diffraction-limited METIS L-M-N-(Q)imager/spectrometer Leiden et al.
A POSSIBLE AO & INSTRUMENT DISTRIBUTION (Nasmyth) Test Camera HARMONI SCAO, LTAO module OPTIMOS MICADO METIS MAORY MCAO module EPICS+ XAO
A POSSIBLE INSTRUMENT DISTRIBUTION (GI & coudé) GI Location envisaged EAGLE with MOAO & SIMPLE with SCAO or LTAO HARMONI LTAO LTAO module P P METIS EPICS+ XAO Coudè Location envisaged for CODEX with GLAO Adaptor, GI feeding unit
AO performance overview (preliminary)(seeing = 0.71 arcsec -- perf @ 2.2 μm – on axis perf) Inputs from T. Fusco
Giving a GLAO-based correction(+ LGSs) • most of the sky & time [cirrus/lasers permitting] • also LTAO for small field/high sky coverage near D-L E-ELT AO Requirements? • Often with an instrument-related 2nd AO stage • wide patrol-field spectroscopy (MOAO/MCAO) • diffraction-limited (spectro)-imagery (MCAO) • extreme-contrast(spectr./polar.)-imagery (XAO) A permanent Internal AO capability(NGSs) to get decent images at all + MIR D-L SCAO • Pushing the envelope on every aspect • Strehl; energy concentration, sky coverage, , ... • but also photometry, stability, astrometry, contrast ....
Thank you for your patience! Thank you also to the whole European AO community for the hard work so far!!!
E-ELT Adaptive Optics overview • Telescope AO: with M4 & M5 correctors + LGSF • Ground Layer AO with 3 NGSs • Ground Layer AO with 4 LGSs • Engineering Single Conjugate AO • Postfocal AO: M4 & M5 units as 1st stage correctors • Laser Tomography AO Module: ATLAS • Multi-Conjugate AO Module: MAORY • Multi-Object AO integrated into EAGLE • Extreme AO integrated into EPICS (NGS) • Single Conjugate AO using IR WFS integrated into MIDIR (NGS+ LGS) • Single Conjugate AO using Vis WFS integrated into instruments (TBC)
On-going research work to reduce spot elongation Perspectives for tomography: comparison of metapupils 3 LGS Central launch 3 LGS Side launch as seen at 10 km altitude less elongation where seen only once Side launch solution open options to use Fractal iterative method to further reduce the laser flux requirement study on-going for MCAO
LGS : choice of a launching scheme Spot elongation and noise propagation • Spot elongation and noise propagation E2E simulation . Telescope = 21m . Scaling factors 6 LGS position : 1 min ring Representative of 42 m Tomographic performance M1 ≡ M2 Even a small gain from a pure performance point of view ! More uniform propagation onto modes ! 36