Presentation on theme: "NAOS-CONICA (a.k.a NACO) for the VLT"— Presentation transcript:
1 NAOS-CONICA (a.k.a NACO) for the VLT 3/25/2017NAOS-CONICA (a.k.a NACO) for the VLTThierry FuscoGérard Rousset
2 NACO HistoryCFT for the VLT Coude AO feasibility study: Feb. 91CONICA contract signed with MPIA et al: 1991VLT Coude AO feasibility study: Matra-Marconi-Space in 92-93VLT Coude AO project (4 AO systems) cancelled: Council Dec 93NAOS concept is proposed by ESO to STC-FC-Council: end 1994CONICA is redesigned by MPIA et al.: end 1994NAOS Preliminary Inquiry & CFT: Dec. 94- March 96NAOS audit: March 96- December 96NAOS contract signed with ONERA et al.: March 97CONICA FDR: mid 98NAOS PDR - FDR: Oct June 99NAOS-CONICA PAE: Sept. 2001NAOS-CONICA first light: Nov. 2001NACO open to the community: Oct 2002~5 years
3 NAOS in figures 4 Institutes : ONERA, LAOG, ODP, ESO 5-year project 3/25/20174 Institutes :ONERA, LAOG, ODP, ESO5-year project~5 Meuros60 FTEsTests in France in 2001First light 25/11/2001NAOS: 2.3 tonsCONICA: 0.9 tons(attached to Nasmyth rotator)3
4 NAOS main features (1/2)… 3/25/2017Two Shack-Hartmann Wavefront Sensors,each including 2 pupil samplings:14x14 (144 valid subap.) and 7x7 (36)VWFS :Spectral range: mm2 interchangeable lenslet arrays(0.29 and 0.58 arcsec/pixel)EEV CCD 128x128 pixels, 16 outputs (ESO)frame rate from 444 to 15 Hzbinning, windowingnoise : 2.9e- to 5.4e-48 configurations!!!IR WFS :Spectral range: mm14x14 array + 2 arrays of 7x7 on 3 fixed detector areas (0.8 and 0.4 arcsec/pix)Rockwell Hawaii 1024x1024 pixelsframe rate from 180 to 15 Hznoise : from 10 to 20 e-36 configurations !!!4
5 NAOS main features (2/2) Deformable mirror (Cilas) 3/25/2017Deformable mirror (Cilas)185 actuators (piezo-stacked), 10 m stroke2-axis Tip/Tilt Mirror: 2.1 mas resolutionReal time Computer (Shakti):0dB Error BW: 27 Hz (V) and 22 Hz (IR)modal optimization (every 2 mn)on-line performance and seeingDichroic Wheel:2 neutral and 3 dichroic BSWFS Field Selector:NGS in 2 arcmin FOVTracking (refraction, flexures, moving object)Observation software:NAOS configuration, control of Field SelectorAberration pre-compensation, choppingOff-line preparation software5
9 Flange to “rotate” CONICA Imaging: 1-5 µmPolarisationCoronographySpectro 1-5 µm: max 2500Fabry Perot: R=1800
10 They lived happy everafter … and they had plenty of photons … … and NAOS-CONICA became NACO …They lived happy everafter … and they had plenty of photons …NAOSCONICACable twistVLT-UT4: F/15VLT Nasmyth Platform
11 NACO challenges And now … let’s go on sky … with a pit-stop in lab High order correction in near IR (Sr(K)=70%)Faint limiting magnitude star in V (Mv>17)IR wavefront sensing for embedded objectsCompatibility with LGS operationMinimization of instrument thermal and sky bkg effectsMinimise the number of optical surfacesno derotator direct rotation of NACOAO with Chopping and Counter choppingVery low flexure requirements (NAOS & CONICA)“background limiter” to reduce dichroic backgroundHigh image quality for CONICA (Sr(K)>90%)Low Instrumental background <1eOne detector for 1-5 m!Many CONICA observing modes: Imaging, coronagraphy, Low resolution spectroscopy, FP, polarimetryAnd now … let’s go on sky … with a pit-stop in lab
13 Paranal re-integration NOOOOOOOO !Oh my god …I have to make it work !YESSSSSSSS ! I’m gonna observe inJ, H, K, L, M …I’m gonna detect exoplanetsThe instrumentalist(use to be an astronomer )The astronomer
14 Let’s go on the telescope Is this going to work??Well … maybe ...Of course it will !!!!!!!!!!
15 And yes … it worked and it is still working High Strehl (K)50%
22 SR loss sources (1/2) No vibration in laboratory Vibrations detected on WFS data:On-skyLaboratoryNo vibrationHz : nm²Hz : nm²Hz : nm²No vibration on ComasVariations in amplitude and occurenceVibration linesNo vibration in laboratoryNothing on internal source: telescope vibrations
23 SR loss sources (2/2) Telescope vibrations: 3/25/2017SR loss sources (2/2)Telescope vibrations:Main influence on Tip-Tilt modes but other excitations detected on high order modesVibrations not compensated for:out of the NAOS temporal bandwidthStrehl loss estimated to 10 %23
24 Without turbulence, SR ~ 93 % in K with pre-compensation Differential aberrations in CONICA and dichroicsAt 1.09 mmSR= 56%SR =66%With pre-compensation by NAOS deformable mirrorNo compensationAt 2.15 mmSR = 89 %SR = 93 %Without turbulence, SR ~ 93 % in K with pre-compensation
25 Conclusion In median seeing conditions: SR ~ 50% at K band; best Sr(K)=64% on skySubstantial compensation with very faint NGS:Mv=17.6, SR=6% (gain of 7)Fully automated operation (VLT software)Many features available in NAOS for specific astronomical observations:IR WFSdifferential refraction, pointing modeltracking on moving object,chopping, counter-chopping241 scientific papers so far=> 34.5 papers per year => Good scientific return !