MAPS Sep. 2023B Night 2: Chilly wind

Tonight is our first *official* night on the telescope schedule, as last night was originally scheduled as an MMTO M&E night (maintenance and engineering) that the telescope ended up not needing more than we did, so they let us have an extra night to focus on our alignment. Thank you MMTO!

Craig and Dan came back up to help out at the start of the night with PISCES and the Top Box, respectively. Craig trained ASU grad student Krishna and me on PISCES operations including filling the dewar to keep it at a chilly 77 Kelvin. Fun fact: PISCES has been on 4 professional telescopes on several mountains around southern Arizona!

[Image description: Three photos showing two astronomers adjusting the instrument PISCES mounted to the telescope, and filling it with liquid nitrogen.]

Unfortunately we had to close the dome because of high winds around midnight.

Luckily the software crew were able to continue debugging by our old MagAO trick of closing the loop with tiny gains on WFS noise!

So I thought I would take some time tonight to lay out all the different systems we are controlling on this run, and the operating stations. Our T.O. Ben took for this great pic at sunset: He is standing outside the dome on the ground and the telescope is tipped over looking at horizon and we are all standing on the dome floor near the dome slit. You can see some of the primary mirror (the big glass behind us) and the back of the ASM and its structure.

[Image description: 9 astro-engineers stand in a metal building that is seen from the outside. The building has a large opening and behind that can be seen a round mirror. Metal beams are in front of the mirror holding out another smaller round mirror. The faint blue twilight sky is seen in back. One of the astro-engineers is jumping for joy, the others are smiling and/or looking wind-blown.]

First we have the big picture of our AO system on the telescope. The ASM is at the top, suspended far above the primary mirror. The Top Box (labelled W-unit here) is mounted directly beneath the primary mirror, and PISCES (labelled ARIES/MMTPol here, because any of our science cameras will go in this spot) is mounted just below the Top Box. The ASM power supply and the AO reconstructor computers are off telescope in the equipment room.

[Image description: A line drawing of the MMT telescope, pointed at zenith. It is a Cassegrain alt-az telescope with a fast primary and a small, agile mount. Colored shapes and lines show how the MAPS components fit onto the MMT telescope.]

Let’s follow a wavefront as it enters the MMT. The first surface it encounters is the primary mirror which is controlled by the telescope operator (this week we have the pleasure of working with Ben):

[Image description: Several monitors at the Telescope Operator’s station showing the status of the telescope and guis for controlling its various components, web cams for viewing dome safety, star finding tools, thermal control, weather prediction and status, and astronomical and geometrical status.]

After the primary mirror it goes to the secondary mirror. The ASM is currently operated by Jess and/or Amali who use the original engineering gui written by Elwood to control the coil currents, monitor the temperatures, and apply their best lab flat:

[Image description: Jess sits in front of two monitors full of guis to control the ASM, view its actuators’ health and safety, and log his observations.]

Next let’s look at the Top Box. Here is its layout: After our wavefront encounters our secondary mirror, it goes through the primary’s central hole to the dichroic just above PISCES, and the bluer portion is passed by the dichroic in reflection onto the optical breadboard in the Top Box. Then it travels (in this picture starting from the left) through the periscope (Oli’s elegant design to give us nodding without the heavy Bayside Stages used for this purpose in LBTI and MagAO). Along this beampath we have the option to insert a calibration laser source used for pupil illumination tests. Next comes the input triplet lens and ADC (atmospheric dispersion compensator). Along this beampath some of the light is sent to the acquisition (ACQ) camera (a Basler) with a selectable beamsplitter wheel. Next are the fast-steering mirror (FSM) that we use to modulate the beam (modulator) and K-mirror (which adjusts for the parallactic angle), then we have a flip mirror which gives the option of either the visible-wavelength wavefront sensor (WFS) or the infrared WFS. Just before this flip mirror is a fairly new addition, a pupil imaging lens (with Lyot stop placed just before the FSM) can be inserted here and a pellicle to a ZWO camera to image the pupil. On this run we are primarily focusing on the visible WFS, the acquistion camera, and the pupil imager.

[Image description: An optical diagram of the Top Box shows optical beams and elements that pass and control the light in the wavefront sensor subsystems.]

Here is a pupil image Grant took last night with the ZWO camera in pupil imaging mode as the dome was closing, to help Oli size the Lyot stop correctly: The bright ring is the sky, the circular shadow is the secondary, supported by the spiders in black, and the white rectangle in the center is the last bit of the primary mirror that can see the dawn sky as the dome was closing.

[Image description: Blurry white ring on a black background. Inside the white ring are four dark diagonal lines making a cross, and a white elongated rectangle with a dark hole in the center.]

The Top Box is currently operated as follows. During initial alignment at the start of the run, a lot of optics must be adjusted manually (often by Oli; this run it was by Grant and Dan). Next we have the movement of remotely-adjustable motors, from filter wheels and the periscope to the modulator (FSM) speed and amplitude. While we have a gui design in progress, these are currently being operated using the original engineering guis of each of the individual COTS components, here is their control station:

[Image description: Photo of a computer screen with several guis for components by Thor Labs and Basler among others.]

The WFS in the Top Box and the ASM above the telescope work together in a closed feedback loop to flatten the wavefront. This is controlled by the AO software CACAO and CHAI currently being written and operated by Andrew, Amali, Eden, Jared, Olivier, Jacob, and Robin. Here are Amali and Andrew closing the loop on WFS noise when the dome is closed due to high winds:

[Image description: Amali sits in front of two monitors and a laptop. The monitors are full of guis, TMUX screens, and displays of the AO system and CACAO. The laptop has Andrew on Zoom.]

Now consider the redder portion of our wavefront. That passed through the dichroic in transmission and went into our science camera PISCES. The PISCES optical path inside the dewar has two cameras (narrow-field 26” f/23 and wide-field 100” f/5), a filter wheel (JHKs and narrow bands 1.113um, H2 2.122um, Br-g 2.166um, FeII 1.64u, and 1.2um), and a Hawaii-1 chip.

[Image description: On the left is a line drawing of the optical diagram of PISCES. On the right is a photo of PISCES mounted to the telescope, which is labeled with PISCES’ components.]

PISCES is operated from our fifth and final computer station in the control room:

[Image description: Photo of the computer screen for running PISCES control software, which consists of a ds9 display of a seeing-limited star at K-band, a terminal, the control gui, and the PDF operations manual.]

It’s 5am (about an hour before dawn) and looking at the weather, we don’t think the wind will clear up in the next hour, so we’re going to bed early. The song of the day is Chilly Winds by the Kingston Trio:

[Media description: Folk group “The Kingston Trio” sings “Chilly Winds” on a stage in the early 60s.]

MAPS Sep. 2023B Night 1: Field trip!

Hello Extreme Wavefront friends, I’m back! Tonight was the start of our first MAPS run after the summer shutdown and it’s the usual packed control room, multi-tasking team, full moon, and beautiful mountaintop observatory!

[Image description: Gallery of photos showing the MMT Observatory at the top of Mount Hopkins, the telescope overlooking the valley, and the moon and clouds through the dome slit.]

MAPS is the MMT AO exoPlanet characterization System and is an ASM-based third-generation AO system with two pyramid wavefront sensors and a suite of science cameras. Our primary focus is on exoplanet science, although the broader diffraction-limited/enhanced-seeing MMT community will also benefit from the return of AO.

On this run we are starting with general system checkout and alignment, then focusing on AO software tasks such as offloading and pupil real-time alignment, as well as on-sky calibration of our interaction matrices.

It was a fun first night with Grant announcing “Field trip!” everytime we asked him and Dan to go up to the dome and adjust something in the Top Box.

By the end of the night we had nicely aligned PISCES and the pyramid pupils.

[Image description: Gallery of photos showing astro-engineers in the control room operating AO software or looking at the sunset; line drawing of telescope and camera optics; and photos of various guis showing starlight manipulated in various ways to show PSFs, pupil images, and pyramid pupils.]

For the blog rules, we’ll stick with the classic/basics: One post per night, one song of the day.

Tonight’s song of the day is a cover of the Cranberries’ Zombie by Bad Wolves:

[Media description: High-production-value music video of the group “Bad Wolves” performing the song “Zombie” as a cover and tribute to the original by the Cranberries.]

MagAO-X 2020A Stay At Home Day 29: AO for Exoplanets

In the days of MagAO-Classic, I would write daily blog posts 3-5 times per week. By the time we got to Day 29 in the run I would be so exhausted I was grateful for anyone to write blog posts. Now the tables have turned and here I am, belatedly showing up on the blog after a month on the mountain at home!

Photo from today on Day 29 of the Classical MagAO run. Here I am at the Clay telescope at LCO on a brilliantly sunny day, supervising the ASM being driven up on the Isuzu truck. (Or maybe being driven down.) I have lured one of the local fuzzy fauna for some snuggles. Looks like I found an Andean Cat. Yes, all is fine here at MagAO-Classic. [Image Description: A woman in glasses holds a cute cat, both lit up by interior light. The background shows a sunlit Chilean mountain scene. Magic of Zoom backgrounds.]

OK so what have I actually been working on? Well, the above picture is actually relevant.

Adaptive Optics (AO) for Exoplanets can be done in various different ways. One difference is the type of Deformable Mirror (DM) you use to control the wavefront. You can use an Adaptive Secondary Mirror (ASM) for better sensitivity to planets that are brighter in infrared (heat) wavelengths. Or you can use a Micro-Electro-Mechanical Systems (MEMS) for better sensitivity to planets that are reflecting the light of their stars (like our Moon reflects our Sun).

MagAO-Classic uses an ASM, and while it has been successful with both infrared planets with Clio and visible-light planets with VisAO, its sensitivity was limited in the visible. Therefore MagAO-eXtreme uses a MEMS, for more precise wavefront control that allows for better sensitivity to reflected-light planets.

I have worked with both MEMS and ASM DMs. In ancient times (pre-Classical) I characterized many iterations of MEMS DMs for the Gemini Planet Imager (GPI), including holding the positions and monitoring what they do over time:

Stability plot of the displacement (measured with a 100-pm-accuracy interferometer) of all the actuators on MEMS device number W10#X in the Laboratory for Adaptive Optics at UCSC. Perfect actuators would be a flat horizontal line in this plot. [Image description: A line plot of actuator displacement in nanometers phase (aka. nm wavefront, rather than nm surface) vs time step since beginning the experiment. Each actuator has its own line, although only a few are called out in color. Most of the actuators were around 0 displacement. A few actuators started out too low. Over several minutes, a few actuators drifted to lower positions, which they are not supposed to do.]

MagAO-X has a similar but more modern MEMS, and my expertise has come in handy. Now in the post-classical world I’m PI of the “MAPS” instrument (MMT AO exoPlanet characterization System). MAPS is using an ASM that we are building ourselves at Arizona. We are in the lab-testing phase and Amali Vaz (click to read her award-winning blog posts) is running similar tests of actuator stability on the MAPS ASM:

Stability plot of the counts measured at the capacitive sensors vs time. The initial jump is a command by the AO operator. A perfect actuator in this plot would be exactly horizontal after that point. [Image description: A line plot of actuator position measurememnt from the capacitive sensor (capsens) vs. time in seconds. Amali has added a small offset to each actuator to shift them vertically on the plot so that they can be distinguished. Most of the actuators are fairly flat, but a few drift slightly lower over time. This is preliminary work and was done with almost no gap and with the thicker test shell, so this is not concerning at this point. Just interesting to start to do these kinds of tests, and to compare to the MEMS.]

The MAPS ASM project was initially led by the original MagAO-C/Clio PI, Phil Hinz. He has moved to a new job to lead the Laboratory for Adaptive Optics (where the above MEMS work was done) and I am now PI of both MAPS and Clio. So this project has been a way back into DM and actuator characterization. Let’s look at some more pictures.

At the start of stay-at-home, we were still able to go into the lab with a whole group of people. Here are 4 people mounting the thin shell on the reference body of the MAPS ASM. From left to right: Grant West, Oli Durney, Manny Montoya, Emily Mailhot. Oli and Manny are eyeballing the gap, and checking whether the clocking is correct. Grant is keeping an eye on the scale, to detect when the magnets start to lift the shell. Emily is controlling the actuator coil currents, and keeping an eye on the shell. [Image description: In a clean room, 4 people are wearing lab coats, gloves, hair nets, and face masks. An optomechanical structure in the center is the MAPS ASM, looking down as if the telescope is parked at zenith and the primary mirror is below. The thin shell of glass rests on a cart with a scale on a lift, and is being slowly raised until contact with the reference body. The reference body is a clear-ish thick glass circle. Above it is the cold plate, similar thickness and copper-colored but aluminum. The actuators are clamped to the cold plate and their cables are black and run up above the cold plate. The electronics consist of 6 daughterboards and 1 motherboard and are at the top of the unit. The four people are focused intently on the work they are doing to mount the thin shell onto the reference body. Once mounted, the thin shell + reference body + cold plate + actuators + actuator cables + electronics = ASM.]
Now that we have come under more strict stay-at-home orders, we are operating the ASM remotely. Here is a Zoom grab from today when Amali was filling Phil in on what she had been measuring and learning. [Image description: A screen grab of a Zoom meeting where the main focus is the web gui being run on Manny’s computer. The web gui has two ASM maps, the one on the left shows the position as measured by the capsens, while the one on the right shows the coil currents as commanded by the AO operator.]

The song of the day is a Classic (that can be pushed to the eXtreme) that I first learned in high school band, Malagueña. I present a study of some of my favorite versions. First the Drum & Bugle Core version, representing ancient history:

Then the classical guitar version, a Classic:

Finally, a special treat, Fuego Malagueña by Esteban featuring Teresa Joy, is the eXtreme version:

MagAO-C 2019B Day 13: TUS home

MagAO-Classic has landed in TUS. This is the last MagAO-C 2019B post.

Here we are at the baggage claim in Tucson. We all made it and so did our bags! [Image description: Katie, Amali, Emily, and Laird are all smiling at the camera, we look happy to be reunited with Tucson and our luggage.]

And I am currently surrounded by cats, who are much better snugglers than vizcachas.

Spot the vizcacha.

Spot the vizcacha. [Image description a brown bunny-looking thing hidden on a brown hillside with some brown rocks and brown grasses and brown scraggly bushes in the reddish glow of sunset on my last night.]

On the day we left I checked that everything was safely stowed.

Clio and the NAS safely stored in the Aux. [Image description: A round black metal circle covers the NAS with its electronic boxes sticking out above like Mickey Mouse ears. Clio sits on its cart, with its electronics rack beside. Very important MagAO tools are also stored here.]

Amali said goodbye to her rock garden.

Amali with the rocks. [Image description: Amali is crouched down to put the finishing touches on an orderly arrangement of ~inch-sized rocks varying in color from black to orangey-red, next to the sidewalk by her room.]

We headed down the hill at 8:30am Chile time and got home to Tucson around 11am MST for a total of about 31 hours travel time.

Roadside shrine [Image description: A tiny house with a saint inside, and a cross and 2 Chilean flags outside. Along the road, with desert-y-looking brown/dry landscape and some hills in the background.]

The flowers were blooming at El Pino and the new dorms for our mid-day rest were really very lovely and extremely comfortable:

We saw Tyson in LSC and heard he had a nice stay at Hotel Enjoy. He was on the same SCL-DFW flight and was nice enough to get me into the club in SCL and Laird in DFW. It was nice seeing you Tyson, hope you made it home safely too!

Overall this was a good run, I think Emily did a great job learning MagAO and Amali did great working with her and refreshing her memory on the LBTI compare/contrast differences.

Jared, Amali, and Emily work to set up for the last night in the Clay control room. (Amali is there, you can find her.) [Image description: Clay control room, with walls of monitors, and AOistas sitting at desks and computers, working away.]
Jared giving Amali and Emily a tour of MagAO-X. [Image description: Everyone is wearing clean-room coats and hairnets; Jared is also wearing a face and beard mask. Jared is pointing at the back of the optics doll house while Amali and Emily look on.]
Good bye Clay and LCO, you did a great job! [Image description: The Izuzu that takes the ASM down the hill to the clean room is parked at the Clay telescope awaiting its cargo.]

The song of the day: Taylor Swift’s Perfect Fight Song by Andy Wu Musicland featuring Pink, Ellie Goulding, and Rachel Platten:

MagAO-C Day 11: Clay to clean room

Last night went great. Now today MagAO-Classic has been removed from Clay to the Aux and the clean room. Night schedules are switching to day schedules. It was a 3-viscacha day at the clean room and many NSF proposals have been worked on, and SPIE abstracts have been drafted and submitted to the extend possible.

Sunset called for some frisbee. [Image description: In the pink glow of sunset, a pink PI throws a flying disk towards the photographer. The Baade dome is basked in a warm sunsetting glow, and the mountains are shown in high relief]
Vizzy and a local bird at sunset, one basking up the sun, one sheltering in shadow. [Image description: A vizcacha in the light, a bird in a shadow, sitting on some rocks and masonry structure.]
Here’s a fox from last week. No reason. [Image description: A fox on the road by the dining hall.]

Now it’s time for more proposaling and some packing too, so I leave you with the MagAO-Classic song of the day: Ylvis – The Fox (What Does The Fox Say?)