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www.bo.astro.it/ maory. Large field of view and ELTs: an impossible marriage?. Paolo Ciliegi (INAF -OABO) on behalf of the MAORY team M ulti conjugate A daptive O ptics R ela Y for the E-ELT. INAF (OA-Bologna, OA-Padova, IASF-Bologna, OA-Arcetri) Università di Bologna. - PowerPoint PPT Presentation
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Conference “Feeding the Giants: ELTs in the era of Surveys” -- Ischia 31/08/2011
Large field of view and ELTs: an impossible marriage?
Paolo Ciliegi (INAF -OABO) on behalf of the MAORY team
Multi conjugate Adaptive Optics RelaY for the E-ELT
INAF (OA-Bologna, OA-Padova, IASF-Bologna, OA-Arcetri)
Università di Bologna
Office National d’Etudes et des Recherches Aerospatiales
European Organisation for Astronomical Research in the Southern Emisphere
Tomelleri s.r.l.
www.bo.astro.it/maory
Conference “Feeding the Giants: ELTs in the era of Surveys” -- Ischia 31/08/2011
OUTLINE
•MAORY OVERVIEW : the multi conjugate adaptive optics module for ELT
• THE LARGEST POSSIBLE FIELD OF VIEW @ ELT from GLAO to DIFFRACTION LIMIT
• SYNERGIES BETWEEN SURVEY FACILITIES AND ELT.
Conference “Feeding the Giants: ELTs in the era of Surveys” -- Ischia 31/08/2011 3
What is MAORY? Multi conjugate Adaptive Optics RelaY for the E-ELT
Corrected field of view– Central unvignetted 53"x53" – Maximum requested field Ø=120"– Technical field Ø=160" for Natural Guide Star search
Wavefront sensing– 6 Sodium LGS WFS
LGS projected from M1 edge– 3 NGS WFS
Wavefront correction– Telescope M4 + M5– 2 post-focal deformable mirrors (4km, 12.7km)
Output ports for science instruments– Gravity invariant with mechanical derotation for MICADO– Lateral port for detached instrument (no mechanical derotation)
Conference “Feeding the Giants: ELTs in the era of Surveys” -- Ischia 31/08/2011 4
What is MAORY?
Client instruments– MICADO
• High angular resolution camera (and slit spectrograph)
• Precision astrometry and photometry
• Required AO correction: uniform with high sky coverage
• Wavelength range 0.8-2.4µm. Field of view: 53"53"
• MAORY thermal background < 50% (telescope + sky) @Ks
– SIMPLE• High spectral resolution IR spectrograph
• Required AO correction: on-axis with high sky coverage
– Others
Conference “Feeding the Giants: ELTs in the era of Surveys” -- Ischia 31/08/2011 5
Overall layoutPre-focal station
Nasmyth platformMAORY
MICADOGravity invariant port
Lateral portArea for detached instrument
Conference “Feeding the Giants: ELTs in the era of Surveys” -- Ischia 31/08/2011 6
Post-focal relay
Conference “Feeding the Giants: ELTs in the era of Surveys” -- Ischia 31/08/2011 7
Performance – Strehl Ratio
Ks 2.16µm
H 1.65µm
J 1.215µm
I 0.9µm
Seeing 0.8 arcsecSeeing 0.6 arcsec
MAORY vs. ATLASATLAS performance courtesy of T. Fusco
Conference “Feeding the Giants: ELTs in the era of Surveys” -- Ischia 31/08/2011 9
Performance – Sky coverage
Although we have 6 LGS projected from M1 edge, we still need Natural Guide Stars (NGS) for
Tip Tilt correction
Sodium layer effects
Conference “Feeding the Giants: ELTs in the era of Surveys” -- Ischia 31/08/2011 10
Sky coverage…. where to search NGS
MICADO
53”MAX FOV 160arcsec
20”
NGS WFS
Conference “Feeding the Giants: ELTs in the era of Surveys” -- Ischia 31/08/2011 11
Sky coverage evaluated at North Galactic Pole Reference conditions: Seeing 0.8", L0 = 25m
Random star counts generated by TRILEGAL code 3-NGS asterisms formed for each trial down to H ~ 21 “Best” asterism chosen. Figure of merit for each NGS asterism
– Measurement noise
– Temporal error
– Anisoplanatic errors (NGS positions and uneven brightness)
Each star is assigned the Strehl Ratio value corresponding to its position in the NGS seach field Ø = 160"
Strehl Ratio comes from MCAO correction (1.5-1.8µm)
Performance – Sky coverage
Conference “Feeding the Giants: ELTs in the era of Surveys” -- Ischia 31/08/2011 12
Performance – Sky coverage
Minimum field-averaged Strehl RatioScience field 53"53" (MICADO)
Sky Coverage
Ks H J I
0.53 0.34 0.14 0.03 39%
0.51 0.32 0.13 0.03 50%
0.49 0.30 0.11 0.02 60%
0.47 0.27 0.09 <0.01 70%
0.41 0.22 0.06 <0.01 80%
Conference “Feeding the Giants: ELTs in the era of Surveys” -- Ischia 31/08/2011 13
THE LARGEST POSSIBLE FIELD OF VIEW @ ELT
LARGE FIELD OF VIEW AND ELT : AN IMPOSSIBLE MARRIAGE ?
Conference “Feeding the Giants: ELTs in the era of Surveys” -- Ischia 31/08/2011 14
THE LARGEST POSSIBLE FIELD OF VIEW @ ELT
The actual imaging camera designed for E-ELT is MICADO characterized by superb capabilities in terms of
sensitivity (K ~ 30 mag AB, 5 sigma , 1-2 ours)
resolution (3 mas pix scale)
and astrometric precision.
LARGE FIELD OF VIEW AND ELT : AN IMPOSSIBLE MARRIAGE ?
Conference “Feeding the Giants: ELTs in the era of Surveys” -- Ischia 31/08/2011 15
THE LARGEST POSSIBLE FIELD OF VIEW @ ELT
The actual imaging camera designed for E-ELT is MICADO characterized by superb capabilities in terms of
sensitivity (K ~ 30 mag AB, 5 sigma , 1-2 ours)
resolution (3 mas pix scale)
and astrometric precision.
The Micado Field of view is 53 x 53 arcsec.
LARGE FIELD OF VIEW AND ELT : AN IMPOSSIBLE MARRIAGE ?
Conference “Feeding the Giants: ELTs in the era of Surveys” -- Ischia 31/08/2011 16
MICADO 53’’x53’’
53 x 53 arcsec field with a spatial resolution at the diffraction limit
level and a 3 mas pixels size is an impressive, huge field of view
that will open new frontiers in may astronomical fields
(see Greggio and Fiorentino talks)
Conference “Feeding the Giants: ELTs in the era of Surveys” -- Ischia 31/08/2011 17
MICADO 53’’x53’’
53 x 53 arcsec field with a spatial resolution at the diffraction limit
level and a 3 mas pixels size is an impressive, huge field of view
that will open new frontiers in may astronomical fields
….but of course is not a survey facility….
Conference “Feeding the Giants: ELTs in the era of Surveys” -- Ischia 31/08/2011 18
WFI ESO 2.2m 2040’’ x 2040’’ (34’ x 34’)
MICADO 53 x 53 arcsec
2 MASS 8.5’ x 8.5’
ACS HST
202’’x202’’
WIRCAM CFHT near infrared 0.3’’/pixel
20’ x 20’
Conference “Feeding the Giants: ELTs in the era of Surveys” -- Ischia 31/08/2011 19
Large deep imaging surveys have formed the backbone of extra-galactic survey for the last 15-20 years and there is no reason to expect this to change dramatically in the coming years.
LSST VISTA VST SASIR
Can we image a Wide Field Imager for ELT that can play a direct role as survey facility?
Network Program “ Wide Field Imaging at the E-ELT : from GLAO to diffraction limit”
PI . M. Arnaboldi (ESO) (E-TRE-ESO-508-0755)
WFI at the ELT
Conference “Feeding the Giants: ELTs in the era of Surveys” -- Ischia 31/08/2011 20
We investigate the possibility for a Wide Field Imager exploiting the full MCAO corrected field
MICADO
53”MAX FOV 160arcsec
NGS WFS
90 x 90 arcsec
Pixel scale : 8-10mas
Balance between
NGS search field
Number of detectors
Conference “Feeding the Giants: ELTs in the era of Surveys” -- Ischia 31/08/2011 22
ELT and Large Field of view
Maximum field of view at a resolution slightly worse than diffraction limit (8-10 mas pixel scale) is about 90 x 90 arcsec.
We can reach bigger field of view (tens of squared arcmin, 5’x5’) but we must accept moderate resolution at the level of the GLAO correction.
These numbers confirm the difficulty of the giant telescopes to work alone as survey facilities, highlighting the absolute need for synergies among different facilities.
Conference “Feeding the Giants: ELTs in the era of Surveys” -- Ischia 31/08/2011 23
SYNERGY --- MAORY and NEAR INFRARED SURVEY
Which is the fundamental “food” for MAORY ?
Conference “Feeding the Giants: ELTs in the era of Surveys” -- Ischia 31/08/2011 24
SYNERGY --- MAORY and NEAR INFRARED SURVEY
In our sky coverage calculation, we simulated the availability of a deep (down to H=21) infrared catalogue
For real observations we need real deep catalogues with:
Reliable stars/galaxies separation.
Accurate position (NGS probe have a FoV of 3’’)
These catalogue must be already available at the time of the proposal in order to check the NGS asterism.
Deep near infrared catalogues will be a fundamental input that forthcoming survey facilities like VISTA and SASIR must provide to ELT.
Which is the fundamental “food” for MAORY ?
Conference “Feeding the Giants: ELTs in the era of Surveys” -- Ischia 31/08/2011 25
CONCLUSIONTHE COUPLED MAORY + MICADO IS A FANTASTIC TOOL IN TERMS OF STREHL RATIO, EE, SENSIBILITY RESOLUTION AND ASTROMETRIC PRECISION
…HOWEVER WITH A FOV OF 53 X 53 arcsec is not an instrument for surveys
Conference “Feeding the Giants: ELTs in the era of Surveys” -- Ischia 31/08/2011 26
CONCLUSIONTHE COUPLED MAORY + MICADO IS A FANTASTIC TOOL IN TERMS OF STREHL RATIO, EE, SENSIBILITY RESOLUTION AND ASTROMETRIC PRECISION
…HOWEVER WITH A FOV OF 53 X 53 arcsec is not an instrument for surveys
We investigate the possibility for a Wide Filed imager @ ELT.
At resolution slightly worse than diffraction limit the maximum FoV is ~ 90 x 90 arcsec, while at GLAO resolution is 5 x 5 arcmin.
…. So Large Field of views and ELT seems to be an impossible marriage !!!
Conference “Feeding the Giants: ELTs in the era of Surveys” -- Ischia 31/08/2011 27
CONCLUSION
…. This impossible marriage implies that the synergies between survey facilities and giant telescopes are fundamental.
As an example we show that large (possible all sky) deep (H~ 21) near infrared catalogues are a fundamental input that forthcoming survey facilities must provide to ELT
THE COUPLED MAORY + MICADO IS A FANTASTIC TOOL IN TERMS OF STREHL RATIO, EE, SENSIBILITY RESOLUTION AND ASTROMETRIC PRECISION
…HOWEVER WITH A FOV OF 53 X 53 arcsec is not an instrument for surveys
We investigate the possibility for a Wide Filed imager @ ELT.
At resolution slightly worse than diffraction limit the maximum FoV is ~ 90 x 90 arcsec, while at GLAO resolution is 5 x 5 arcmin.
…. So Large Field of views and ELT seems to be an impossible marriage !!!
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