MIRAC – Extreme Wavefront Control Lab

MAPS April 2025A Night 2: Toky(A)o Drift

Not a sunset picture. I took this earlier in the day (I actually went outside! It was not 100 degrees out, so I decided to enjoy the weather.)

For the first time, Bianca and I are the only AOistas at the AO station for the entirety of a run. After last night’s work, we felt motivated to close the loop. In fact, I would even say we felt confident in our abilities to do so. We began the start of the night CACAO processes while making constant WFS pupil adjustments. Normally our pupils don’t drift this much, so we decided to check the pupil imager. Sure enough, our pupil image was vignetted.

Flashback to last night:

After alignment, we worked on booting up CACAO and acquired an RM. While checking RM modes, we noticed modes were not looking AO ready. They should not have chunks taken out of them. This led us to check the pupil image. We saw the same vignetting we see today.

Not smooth RM modes. Notice the chunk taken out in the bottom right corner of each | Photo Creds: Bianca Payan.

Vignetting as a result of MIRAC being off the center of rotation.

Our solution was to adjust alignment in the periscopes and MIRAC dichroic. With the remaining time in the night, Bianca and I were able to get to the part of the CACAO process where we open up the gains gui that allows us to close the loop. At this point, we did not notice any extreme drifting. Unfortunately, we were receiving errors while trying to open the gui, and sunrise was just around the corner.

Back to present:

Just as last night, Oli and Maggie adjusted the MIRAC dichroic and top-box periscopes. Bianca and I proceed to CACAO, but continue to face the same drifting issue. We now realize this vignetting/drifting issue is very repeatable. Our suspicion is that this is due to MIRAC being off the center of rotation. To test this, we realign to the telescope chief ray to see how AO performs without MIRAC. By the end of the night we are able to close the loop on 20 modes with minimal drifting. This was a bit tricky, as we did not have a PSF to reference as we were closing the loop (MIRAC is very useful for PSF imaging). Unfortunately, we cannot easily determine how good the loop is working purely based on vibes and what we can see from the acquisition camera.

Bianca and I closing the loop on 20 modes without the MIRAC PSF.

We came to the conclusion that we do not want to proceed using MIRAC this run. Our plan is to hopefully get PISCES installed before tomorrow night so that we can continue with the optimal setup to perform AO. To be continued…

Stay tuned for the next chapter of the MAPS April 2025 run!

The song of the night is “Drift Away” by Uncle Kracker.

MAPS Feb. 2025 Night 4: Oh Connection, where art thou?

Hey everyone, I realized I didn’t introduce myself properly in my last blog post, sorry about that. I am Krishna, 3rd year PhD candidate at ASU. I am working with Jenny and Katie to characterize MAPS AO performance 🙂

It was a night like any other except we started on a little bit of rough patch. There was a brief connectivity issue with the WFS. So, the citizens of AO nation (Amali, Lauren, Bianca) worked hard with Andrew to get it back on track. It was not just this but also the WiFi that was being a troublemaker today. While this WFS issue was being worked on, Alyssa and I took organized exposures of darks and sky backgrounds at different bands.

A screenshot from Jarron showing that our ping speed of our WiFi connection was 200ms!

Eventually, after the WFS fix, it was realized that the pupil position was offset from yesterday, so we had to go to lower than 100 modes of AO correction like we did yesterday. Well, that’s a bummer.

Despite all the trouble, we were able to successfully observe 4 targets with varying R magnitudes at a constant(-ish) airmass. Hoping everything goes smoothly with the reduction, this would allows us to see Strehl as a function of magnitude (fingers crossed). We pushed as much as we can to the end of the night but clouds, once again, put a limit on our happiness.

As Sting would say – “He looked at the chart but he look in vain
Heavy cloud but no rain“

Song of the night:

MAPS Feb. 2025 Night 3: “Clear Skies”

Hello! I’m Alyssa, and I am new to this blog. I am a visiting grad student from the University of Michigan that joined the MAPS team on this 6-night run. This will be my second observing run ever!

The MAPS team headed up to the summit tonight! The skies looked more promising than previous nights.

We had some clouds here and there with periods of high winds. But that quickly died down from up to 35 mph down to 0 mph over a span of a few hours. When aligning the pupil for MIRAC5 and co-aligning with the AO WFS, we have initially found that the source position was barely on the field of view of the detector. Since there is a new dichroic lens in the optical system, Manny and I went up to adjust the actuators near the dichroic to see if we could center the source as much as possible. Luckily, this had solved the issue to a good degree, and after getting through the cloudy and windy moments in the night, we were fortunate enough to start taking some science data tonight with some targets.

With some progress tonight, I want to take a moment for some notable quotes given out from none other than Krishna:

“What is the name of the dog in Scooby-Doo?”

“Is the loop looping?”

“Also, Manny, you look like a Rapper.”
Krishna

Manny and Krishna strike a pose as your local MMT rappers — Manny and Krishna pose as your local MMT rappers

Song of the night featuring one of my favorite bands:

https://www.youtube.com/watch?v=yhWWlFme0dU

MAPS Feb. 2025A Night 2: The Fog

As much as I hate to report it, the MAPS crew is once again trapped in a cloud. For a few days now, the forecast has consistently predicted high cloud coverage for all of tonight. To be sure, we performed our own professional survey of the sky at sunset. Yep, those clouds look cloudy, and it seems like they want to stick around with us.

We decided it was best to make ourselves cozy in the dorm common building while waiting for any break in the clouds. Bianca and I took this time to practice AO/CACAO set up . ݁₊ ⊹ remotely. ݁˖ ⊹ ݁. We have ran through this process four times between the two of us so far this run without making any dire mistakes. Amali has trained us well! Additionally, we properly troubleshooted an issue with the visible wavefront sensor camera, which was reporting a frame rate of ~2000 instead of the expected 500.

Unfortunately, there is not a fireplace here. Instead, we turned on all of the “cozy” lights (minus the lamp that had exposed wires in place of prongs on its plug) and a space heater. For some ambient noise, we turned on the tv to the H&I channel. This was not by choice, but the remote wasn’t working. Walker, Texas Ranger (5.7 stars on imdb), featuring Chuck Norris, was playing. I think the cheesy acting and ’90s aesthetic of the show really helped set the vibes for the night.

Our cozy setup. Note the 94% humidity reading.

I made a few trips outside throughout the night. The fog that engulfed Mt. Hopkins was quite dense, and I could not see further than five feet in front of me. Around 2 AM, we declared the night to be unobservable.

The song of the night is “Clouds” by One Direction, which is featured on their best album (in my professional opinion): FOUR.

Bonus song because it is February 14th:

MAPS Dec. 2024B Night 5: The big W problem

Usually you would think, the big W problem for an observing run would be Wind. And usually you would correct… but not this time. When we went to sleep today morning, we were prepared for facing clouds at night but not Water shortage. There was no water at the bowl…would be a statement a thirsty dog would say (maybe, idk I don’t speak dog yet). But thankfully, after a brief 4 hours, we got water running. So, we started our climb to the summit, in our cars. For Jorge, however, it was indeed a climb because he chose to walk to the summit.

When someone mentioned yesterday that we might want to increase the AO modes to 100 for this run, I personally thought it would take some time (to dot every t’s and cross every i’s). But Amali had it working in ~20 mins! So, just for fun, Jorge and I started looking at bright exoplanet hosts. The plan was to observe a planet hosting faint-ish star (Vmag>5). But we stumbled on something better. Not only was it a faint star (Vmag = 8.14), but also the only exoplanet system (WASP-33) to have its high-resolution observations taken with ARIES back in 2016 A.D. But wait, there is more, the planet (WASP-33 b) would soon be in an orbital phase where it would “emit” radiation before going behind WASP-33. So, we thought we would try to hit two stones with one bird — close the loop with 100 modes on a faint target, and capture WASP-33 b’s planetary emission.

The first task was a success! We were able to close loop with 100 modes on the faintest target so far! But regarding the second task, MIRAC grew impatient during the course of today’s adventure and began heating up so most of the images we took of WASP-33 were overwhelmed with noise 🙁

It might not be the best looking PSF there is, but it was still a great news!

Manny quickly figured out what must be heating up (or not cooling down?) MIRAC — one of the cryo lines was not tight. After this fix, we decided to let MIRAC cool down for a while before we restart taking data. By that time, WASP-33 b had already been eclipsed behind the star so we switched to a slightly fainter target for the rest of the run. The rest of the night was just about maintaining the loop, observing the star at multiple altitudes in multiple bands. This night had all things W-centered — Water, WASP-33, Wemperature of the detector.

According to Jarron, only a 0.5K change would worsen MIRAC performance … and we were hitting a difference of 7K .

P.S. Shoutout to Jorge for helping me out with the text, both our brains were at 50% capacity by the end of the night so we needed to team up.

Song of the Day