Laird Close – Page 3 – Extreme Wavefront Control Lab

2016A Day 8: Surprise !

fingers crossed — Look only 10 little Communication errors all night long!

Tonight went really well we only had 6 communication errors on start-up of the ASM (whereas we often have thousands but most don’t bother us) — so the ASM is enjoying this warm weather we are having. As you can see for the photos below we had a surprise at the end of last night when the telescope’s instrument rotator got stuck with MagAO upside down. This was exciting for us since the Infrared camera Clio can’t be filled up if it is upside down. The telescope crew quickly fixed the problem after breakfast and Clio was filled with liquid nitrogen by 9AM. So all is good. Tonight the telescope rotator has been great.

What is wrong with this picture? — The MagAO instrument scientist is concerned

We have had another great night of low winds and great seeing for almost the whole night. Tonight is my last night. I’ll be back in 2 weeks to help with the GMT Phase Cam experiment and to take down the system. Katie and Jared will continue to be the real heroes of MagAO –keeping the system/AO/Clio/VisAO all running perfectly as usual for our visiting astronomer friends.

So as the seeing gets worse I need to take my leave of running the AO system — and so today’s song:

Summary of MagAO’s first Science Run

From April 5 to April 21 we were helping other folks use MagAO. It took the work of a large team of excellent folks to make all this happen. In particular, we had the expert help of TJ Rodigas, Katie Morzinski and Vanessa Bailey who all looked after Clio with expert hands. Jared’s VisAO camera was also helped out by Ya-Lin Wu, and Kate Follette. The MagAO software became much more stable after the engineering period at the start — thanks to the hard work of Alfio Puglisi and Jared Males. The AO system was run by Katie and Jared and myself (running the AO system was pretty easy by the end of the run — so easy the PI could do it).

We also benefited from excellent support from the Magellan mountain staff. Juan Gallardo and his team expertly helped install (and uninstall) the adaptive secondary mirror, the NAS, and Clio (while also doing the same for the f/5 and the f/11 secondary!). Povilas Palunas did a great job of getting the f/16 guider running smoothly.

Also I’d like to thank all the excellent observers that submitted proposals to use MagAO and especially those that came down to visit us at Clay. These were our visiting astronomers: Jorden Stone (U. Arizona), Brett Addison (and Graeme Salter remote; UNSW Australia) , Alycia Weinberger, (Carnegie) Timothy Rodigas (Carnegie) Kate Follette (U. Arizona), Jared Males (U. Arizona), Subo Dong (PKU, China), Sebastian Perez (U. Chile), Francois Menard (U. Chile), Amanda Bosh (MIT), Stephen Levine (Lowell), Jennifer Yee (Harvard) and John Monnier (U. Michigan; remote) . Thanks to all for making this such a scientifically productive (and enjoyable) run!

Here is a summary of the run from the results of the Run reports that are filed at the end of each run. Overall I’m really happy with how well MagAO worked (especially after the first week) with very little “down-time”.

not bad — Here is the amount of down-time from MagAO/Clio/VisAO during the whole science run

The Reviews Are In

Here are the reviews of how users felt the support from the MagAO team was for AO operations (1 is the lowest and 5 is “well above acceptable” and the highest rating possible):

We are loved — Here is the nightly rating of the support provided for MagAO

Also here is the rating of how well users felt MagAO/VisAO/Clio performed:

"It worked better than I thought it would" — Rating for each night of the MagAO Performance

So it looks like MagAO/VisAO/Clio did very well this run. Of course, it was the nightly support from Jared and Katie that helped make all this really happen. So here is a photo of them finally getting off the mountain after a month!

Final Status of “Unpacking Run”

After 17 days here at LCO Jared and I are heading down today. Overall the “unpacking run” was a success.

1) Secondary Mirror (ASM)
with the leadership of Armando and Marco (Arcetri) with Mario and Frederico (Microgate), and Rich (Arizona) we unpacked, flipped, cleaned, clocked, and installed the shell on the ASM. Victor (Arizona) prepared a special wedged interface plate that exactly positioned the ASM on the mount in the correct X, Y, Z, and ThetaX, ThetaY to match the optical axis of Magellan (thanks to Tyson and Juan for help with the final adjustments to this complex interface plate). The TSS shell safety system was (for the first time) made fully operational. The ASM was fully characterized with the windscreen on. All ASM tests and calibrations were redone and the ASM is perfect working condition.

see

/uncategorized/asm-performancesverification/ for summary details and plots.

Victor (Arizona) “whipped up” a novel cooling system (and NAS bulkhead) for the ASM that worked well — but needed up to 10 bottles of ice each day — thanks to all the staff that helped us get ice each day…

2) Active Optics Guider
Also from Carnegie Tyson and Alan (with lots of help from Povilas, Juan, and the excellent technical support from the rest of the LCO and Magellan Staff) were able to install and successfully test the active optics guider on the ASM.

see

/uncategorized/guider-demo

for a movie of the guider moving from the center of the field to its “off” position as it hands off the guide star to AO.

3) Pyramid Wavefront Sensor (PWFS)
Jared (Arizona) and Laird worked hard at aligning the PWFS optics, testing, and final cabling of the PWFS. For the first time the whole system was tested with all the electronic racks (and their internal fans) mounted on the NAS with the PWFS. The vibration damping system of Tyson seemed to work well –as there were no vibrations from the fans seen by the PWFS (or VisAO CCD). This is a big relief. All the PWFS optics were aligned as well as they were during PSR in Italy (they were also given a much needed cleaning). Also we can now reach our goal 4.3 electrons of read noise in our most sensitive CCD39 mode (with all components powered). There doesn’t seem to be any addition noise from any of the other components or motors. This is also a big relief.

4) Visible light science camera (VisAO)
Jared worked hard on the VisAO camera and computer. The one disappointment of the run was that the motherboard of the VisAO computer was likely damaged while mounting it on the NAS (for the second time). Perhaps even more annoying was that Jared’s spare motherboard also failed! However, Magellan kindly let Jared borrow a spare computer and he was able (in a day) to have the whole system up and running again on a rebuilt computer! The VisAO camera had some work done it as well. We installed a new gimbal mirror, Derek’s new ND3.22 in the coronagraph wheel, and cleaned and tightened up the optics. Derek’s new baffle tubes were also installed. Also we installed a new “off-sky” fiber laser alignment system that works quite well. Overall, we made the sharpest images yet with the VisAO camera (0.02 arcsec) and we are ready for commissioning in November. Also the noise and sensitivity were nominal for the CCD47 as well.

See
/uncategorized/unpacking-day-15-all-wrapped-up/
for some final images of the ASM and VisAO in its coronographic mode

5) Communications with the Telescope
Jared and Glenn (Magellan) worked on making sure the AO system’s AOI software could talk to the Telescope’s M1, vane ends, and mount (for offloading Astigmatism, coma, focus, and Tip-tilt). Good progress was made on that front.

The success of this run required the help and cooperation of a great many people. Despite transporting 17 boxes halfway around the world not one item was damaged by the trip! This is testament to the excellent handling and packing of the items — many people helped in this, I’d like to especially thank Roberto, Dave, and Povilas (LCO), Edilia (CTIO), Earl (OCIW), Ganni (Fiorino shipping), and Runa, Carmelo, Armando, Marco (Arcetri) for a great (and surprisingly complex) shipping job! Also I’d to thank Dave, Miguel, Mark, Povilas and the whole LCO crew for being so incredibly helpful and responsive throughout this whole period.

Things are looking good for first light in November.

thanks Laird

PS — I’d also like to thank Jared and Marco for keeping this blog up to date and so interesting for the whole run!

Movie of the Loop closing

Here is a short film of the VisAO camera at i’ (765 nm) in 0.8″ seeing (33mph wind) with the loop open (0.3% SR, FWHM~0.6″) and closed (55% Strehl, FWHM=0.027″) at 800 Hz (400 modes) in the test tower.

This is a >180 increase in peak counts (and >20x gain resolution) obtained by turning on the loop!

Note that the PSF is saturated out to the first Airy ring in this (rather poor) stretch. The red dot is the focus light from the videocamera (ignore it).

A Better Closed Loop

On July 21 we closed the loop again (but without wind on the outside of the tower). In these calm conditions we were able to obtain 55% Strelh at i’ (765 nm) which is excellent correction in 0.8″ seeing and 33mph winds. I attach a log10 stretch image below to show the very high contrast PSFs that are obtained with the Magellan AO system. This is slightly better performance then was predicted for an R=8 mag guide star in a 33 mph wind with ro=14cm at 0.55um. Normally at Magellan the seeing should be better (and the wind lower) than what we simulated here, giving us some confidence that VisAO will be an excellent visible AO science camera in >75% of the weather seen at the Magellan telescope.(clockwise) perfect PSF, the MagAO PSF, The AO ON PSF, and the AO OFF PSF (Log Scale)

Note by Jared: due to the way turbulence is simulated in the tower using the mirror itself, there is some missing power in the modes higher than ~585 (the number of actuators on our mirror). This results in an optimistic fitting error during these tests. We can estimate how much lower Strehl at the telescope would be due to this unsimulated turbulence using some AO theory (see Noll 1976). Our most conservative estimate for this correction brings our telescope Strehl down to 37%, from the 55% measured in the tower. Compared to the correction calculated by a more empirical method for the LBT (see Esposito 2010) this correction is probably a little large (resulting in a low estimate for Strehl). Even with this conservative correction, our tower results are exceeding our performance predictions for an 8th magnitude guide star by more than 5% Strehl. This is very exciting!