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LBT FLAO system: an attempt to highlight Piero’s views about the project. Disclaimer: the opinions contained in the presentation are shared between most of the memebr of the AO group. However they sometime differs from the opinions of Piero !!!!. Talk summary. The FLAO system main components
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LBT FLAO system: an attempt to highlight Piero’s views about the project. Disclaimer: the opinions contained in the presentation are shared between most of the memebr of the AO group. However they sometime differs from the opinions of Piero !!!!
Talk summary • The FLAO system main components • The adaptive secondary mirror • The wavefront sensor The system performance in solar tower & on sky Possible FLAO upgrades for LBT & ELTs
The Principles of Piero-dynamics Avoiding people get satisfied with what they have already found. 2) Convincing people they can do what they think is possible....and spending days of discussions convincing them. 3) Supporting the idea that lenghtly plans can be unnecessary. 4) Disappointing people changing idea when new technical reasons show a new (but barely possible) solution. Applications of Piero-dynamics principles to the FLAO system development, realization and upgrades, as known to the Arcetri AO group, will be highlighted in red in this presentation.
....as planned in 2001 A system Overview • LBT672a unit • 911mm diameter • 1.6mm thick, (Mirrorlab) • 672 actuators • Settlingtime < 1ms • 30nm WFE • LBT WFS unit • Pyramid sensor • 30x30 to 5x5 subap. • Tilt mod. 2-6 l/D • 1Kfps max [30x30]
The adaptive secondary mirror Missing picture of P25 prototype. The pros: no one even think in 2001 of realize such a complicate thing for a real telescope. Validation: a sentence from Guy Monnet, head of Instrumenation department at ESO ,(a very polite and competent person): «Simone, I do not think this is a good project for a post-doc . You should find something realizable» The cons: it can not provide correction in the visible and/or can not achieve contrasts of 10^-7 easily. However upgrades are still possibles.......
The pyramid WFS The pros: other people consider the idea totally useless. Tipically Italian. It sounds like buying a a shirt from Armani paying 1000 Euro for nothing. Very easy to realize. Notes from Arcetri AO meeting (2001): «Piero, we can not build it in 1 week!?!!» «Simone , be serious, we are speaking of a pyramid in front of a CCD......» The cons: In the current project it uses only 30x30 subapertures and required at least 141 photons per mode to achieve SR of 80%. In H band. The target was 1 photon per mode.
System development schedule # of person involved (2001) => 8 # of years required => 3.5 Hmmm... too slow. Do we really need this stuff ?!! Start date September 1°, 2001 End date November 22°, 2004
System performance at acceptance test. Evaluation of system performance in the Arcetri AO group is not seen as particularly positive. Even if consistent with numerical results. A general important remark: why not going to visible wavelenght ? Why only 78% in H band ? Why stopping at mag 16.5 ? Still 30 photons per mode per frame. Here, we have contrasting opionions between Masters: P. Salinari: «78% only, uhm...» R. Ragazzoni: «Simone, astronomer will blame us all for ages. Do not promise unachievable results» The solar tower acceptance test took place in December 2009
FLAO system installation @ LBT February 9th --March 17th .
FLAO system installation @ LBT February 9th --March 17th .
FLAO system installation @ LBT February 9th --March 17th .
FLAO system installation @ LBT February 9th --March 17th .
FLAO system installation @ LBT February 9th --March 17th .
FLAO system installation @ LBT February 9th --March 17th .
FLAO system installation @ LBT February 9th --March 17th .
First on sky results: May 25th Some of the first closed loop images acquired the 25th of May The object: HD 124085, K0, R=7.5 , I=6.9, H=5.8, Triple Star The atmosphere: seeing0.6arcsec V band Elevation58..64 FLAO parameters: 1 KHz, 30x30 subaps, 400 correctedmodes Results: SR H 65%..73% Intensitiesbetween open and closedlooprescaledfordisplayingpurposes. 3.2 arcsec LBT InfraRedTest Camera images: H band, 10mas/pixel scale From FLAO press release June 6, 2010.
The HD 124624 images and SR The reference: HD 124624 [14:13:54.67 +37:37:34.2] R =7.1, H=4.4, J=5.1, K5III The atmosphere: seeing0.9arcsec V band FLAO parameters: 1KHz, 30x30 subaps,400 correctedmodes Best SRs achieved! 85% H (1s) 47% J (1s) 0.72” J Band 46.6% SR in 20 sec H Band 75% SR in 12sec
High H band SR images The reference: HD175658, R =6.5, H=2.5 The atmosphere: seeing 0.9 arcsecV band FLAO parameters: 1KHz, 30x30 subaps,400 correctedmodes
First on skyresults: a 40mas separationbinary Star companion Image data H band 4s exposure time SR > 60% (no correction for 2nd star flux) FLAO parameters 30x30 subaps 400 correctedmodes 1Khz frame rate
H band SR vs star mag & seeing Twoon skyrunsperformed: May 25th-June 3rd, June18th – June 25th Averagevalueofclosedlooptimeis 4h/night over 12 nights. K band SR valuesscaledfromprevious plot 2MASS J19460752+2231122 R+I mag 17.0 SR 6.2% H band FWHM 0.1 arcsec DIMM 0.9” 7x7 subaps 36 modes, 200 Hz 16 ph/subap/frame 2MASS J19334425+1947482 R+I mag 17.8 FWHM gain 1.4 DIMM 0.9” 7x7 subaps 5 modes, 100Hz 18 ph/subap/frame Eachpointcorrespondto a different target and reportsanaveragevalueof the achieved SR. Seeing values measured by LBT DIMM
Some results from last run, 18-28 October Mag 17.5 Peak’s ratio ~ 3 FWHM TBD Magnitude 16 Peak’s ratio ~ 10 FWHM < 0.1 arcsec Mag 12.5 Peak’s ratio ~ 30 FWHM DL Mag 16.0 Peaks ratio ~ 10 FWHM < 0.1 arcsec Seeing values between 1.0 and 1.8 arcsec. Performance shown in term of PSF difference between open loop and closed loop 93% SR (H band, 20sec. exposure)
Imagingglobular cluster NGC6341-M92 The reference: R 11.5 The atmosphere: seeing0.7arcsec V band Elevation 58..69 FLAO parameters: 0.5KHz, 15x15 subaps, 153 correctedmodes LBT test camera Limiting Magnitude H = 21, in 10minutes (with AO on) FLAO H Band 8min HST WFPC3 H Band 20min However from Piero-Dynamics point of view we know that the most desired results is not been presented up to now..... Dati sulla configurazione del sistema adattivo durante la osservazione ~10 arcsec Composite imageJ+H Composite imageJ+H
First on skyresults: correctedimage at 850nm Star mag => R=9.3 J=7.5 H=6.7 The 850nm SR isconsistentwithMarechalscalingof 65% SR in H band Sensor: E2V CCD47 Filter 850nm; BW 40nm Texp=6s, scale=20mas/pix Drizzlingof 5 images SR~20% FWHM=40mas (DL=20mas) From one Piero’s email: «E seguito a sopportare (pazientemente) . . .la mancanza dei promessi attachments!» «I keep waiting (patiently) for the missing promised attachments (of CCD47 images)» IRTC H Band, scale=10mas/pix, SR~65% Horizontal cut
The upgrade path: a first step with LLLCCD Now: about 70% SR with mag 13: sounds better!! Plot courtesy of M. Carbillet ( probably the next PI of FLAO development at LBT) and A. Riccardi (App. Opt, 2010) Finally a useful system: 10% SR in K band with mag 18. .....It seems we are again on the right track: no one would believe a SR of 10% with an 18 magnitude star or 85% SR with magnitude 13.
A more sounding upgrade: add LGSs and a post focal corrector: MCAO correction in the visible Change the already existing AGW unit (already proposed by ML Hart), and add a post focal deformable mirror conjugate to your favorite locations. Use multi-LGS to realize MCAO in the visible over FoV of 10/20 arcsec or more. Pros: -people finally are convinced: the italians are crazy. -Easiness of realization -Need many actuators Cons : no cons. -One warning: time scaling from previous FLAO system unpracticable (10 years for NGS, 40 years for LGS ?). Point to be revised. Baseline workaround: hire younger (cheaper) people for the team......
What’s next: E-ELT Already good chances to place an adaptive secondary technology mirror on the EELT. This has been the critical step to divert LBT on a completely unforeseen path. Unfortunately people today are more suspicious...... (8.4x5=42) GMT They have in the project adaptive secondaries and pyramid sensors. So here an upgrade is straightforward. TMT Seem the more difficult to convince. However, who knows.......
One more Piero-Dynamics applications to ELT ELT: of course here at least one important aspect has been neglected: AO in the visible with 160000 actuators (on primary mirror segments) Pros: Achieved angular resolution: 2.5 mas Detectable magnitude (scaling from 8m telescopes): mag 33 in H band with 1h integration time & SNR=3 Cons: ??????
Acknowledgments: The Arcetri AO group wants to thanks Piero Salinari, the inventor of Piero-Dynamics, to make all this possible......... GRAZIE PIERO FLAO system@ LBT: 85% SR (H band), Rmag=6.50 seeing = 0.9