Season’s greetings from the XmasWCL

There’s one upside to an atrocious windowless office in Steward: it makes your Christmas lights look nicer.

The Principal Investigators in place of pride at the top: Katie, Laird, and… Jay. Wait, that doesn’t sound right.

The Xmas Wavefront Control Lab celebrates in style, with only the finest Dollar Tree Christmas decor. They weren’t selling stockings this year, so it’s good that Jhen Lumbres bought a bunch back in 2019.

I would also like to announce the mission patch sticker for 2021 (really putting the miss in mission):

I haven’t named this guy or gal yet. Maybe Robert Bobcat? (Bobby Bobcat to friends.)

As the saying goes: if you’re not queasy, you must not be paying attention!

If you’re lucky enough to have a 2020 mission sticker, you can make them do this:

It’s not much, but it’s something.

Note: Anyone spreading rumors that this will require a 2022 swing-and-a-miss-ion sticker design to complete the ‘ronamoon should be kicked in the knees.

Song of the Day

Today’s S.o.t.D. was chosen by Logan Pearce, nine time winner of the official Star Trek fan club “dankest memes” competition.

“Let it Snow” by, uh, Star Trek?

Happy Thsmksgiving!

If you haven’t learned by now, here in XWCL we like to get festive with decoration. We’ve posted our past Christmas decorations, but it doesn’t end there. We’ve also decorated for Thanksgiving, but it somehow never made it to the blog… until now.

Flashback to November 1st, 2017: Lauren and I decided that the office was in need of seasonal decor update. We put up a small Christmas tree and a door wreath. It was very lovely and festive. It didn’t last long, as we were immediately commanded to remedy the situation.

Back to the drawing board, I guess.

But, in this group, we do not easily give up. The next year, we came back with full Thanksgiving decor using contributions from members of XWCL and CAAO. I present to you, lovers of the blog, our beloved paper hand turkey decorations:

The 2018 paper hand turkey decoration wall, showcased on the bulletin board in front of Jared’s former office at N434. This is the same location we put up the Christmas stockings.

Paper hand turkeys are the epitome of Thanksgiving decor. For any person who attended elementary school in the United States, paper hand turkeys are the most probable fall craft on the agenda. In making our paper hand turkeys, we wanted to embody that same enjoyment from our childhood. I highly encouraged people to sign their name with their non-dominant hand and in crayon.

MagAO-X PI approves of the paper hand turkey crafting agenda.

Unfortunately, we never had the opportunity to redo the paper hand turkey wall. In October 2019, Steward Observatory was undergoing its first renovation and relocated the entire 4th floor north side personnel to temporary office space on the 3rd floor. Additionally, the MagAO-X team was busy in Chile with their first light run. We didn’t get our offices back until December 2019. We had no paper hand turkey wall in 2020 due to the pandemic. In summer 2021, we experienced an office shuffle. We moved to the conference rooms and offices at the other side of the hallway, with no bulletin board easily accessible to post our creations up.

Despite these lost opportunities, the paper hand turkeys continue to live on. Jared likes to keep his paper hand turkey on the bulletin board inside his office, so he can look at it year round in the few moments he sits in there. We currently have a few old and new ones posted up in the XWCL graduate student office space:

Paper hand turkeys in N412. The creativity is boundless!
Photo credit: Logan Pearce

Happy Thanksgiving, from XWCL. If there’s anything I’m thankful for, it’s this research group – I’m making it to the finish line of graduate school strongly due to the assistance of everyone in XWCL and CAAO. I hope you, dear reader, get the opportunity to celebrate with who and what you’re thankful for.

Song of the Day

One of my staples growing up was the Charlie Brown holiday specials. My brother and I would watch them on VHS. I think at one point we accidentally had 2 copies of the Charlie Brown Christmas? I probably should watch this again, maybe today (if I don’t fall asleep halfway through from a food coma or writing my dissertation, whichever one comes first).

Vince Guaraldi Trio – Charlie Brown Thanksgiving Theme

Pyramid Schemes & Piston Dreams

For about a year, Laird, Alex H., and I have been putting together the protoype-High Contrast Adaptive Optics Testbed (P-HCAT). P-HCAT sent half of the simulated GMT pupil to the “Holey Mirror” which, as the name suggests, is a mirror with a hole in it.

Holey Mirror

The holey mirror is able to simulate a piston differential with a piezo-controlled mirror sticking through the hole. This light was sent into MagAO-X and the PyWFS was used to sense piston. The next phase of the project was adding post-doc Sebastiaan Haffert’s Holographic Dispersed Fringe Sensor into MagAO-X. This 1″ optic is able to interfere each segment of the GMT pupil with another then disperse them so we can back out the piston differentials. We got some very interesting results we plan on sharing in some upcoming papers!

P-HCAT aligned, not sending light into MagAO-X through the hole in the wall, but rather to a Basler science camera via a fold mirror

The next step is to convert P-HCAT into simply HCAT. This new and improved version will have a concept known as the “parallel DM.” This involves sending the entire GMT pupil onto a reflective 6-sided pyramid, a hexpyramid, which will send the light to 6 separate deformable mirrors. The central segment will pass through a hole in the center of the pyramid.


Manufacturing a hexpyramid with a central hole is no small feat. We are super excited to finally have our hexpyramid in the lab and ready to play with. This week we put it in front of an interferometer to check surface quality. To mount an optic this complex you need to be creative to say the least. See our makeshift mount below. We are happy to note the pyramid is very photogenic – it doesn’t have a bad side!

Hexpyramid mounted in front of interferometer

Piston Control is a fantastic mode of risk reduction for the Giant Magellan Telescope and we are so happy we get to be a part of this effort!

Orbital Mechanics Trivia

As a viscacha, integral and differential calculus are beyond me. However, it does seem to be spring again here in the southern hemisphere, and my calendar indicates it has been one full year since the last October 14th we saw.

(I’d double-check my facts with some of the cientificos, but I haven’t seen them in a couple years. I hope they’re doing okay.)

This means that the Earth has completed one more turn about the Sun, and the P.I. is a year older and wiser. In celebration of his wisdom, please enjoy P.I. utterances, available where-ever fine quotes are sold.

Song of the day

“Hard to Kill” by Bleached

Happy 5 Year Anniversary, CACTI!

Today is the Autumnal Equinox, the official end of summer and the start of autumn in the northern hemisphere. Autumn doesn’t really mean much here in Tucson, except our days of constant 100+F heat is waning down. (This does not barricade me from getting a PSL.) A more important date is 8 days away on September 30, which is the end of monsoon season in Tucson. Currently, we are at the 3rd wettest monsoon season this summer, a welcome break from last year’s missing monsoons.

Accumulated precipitation record for Tucson 2021. According to National Weather Service, this is the 3rd wettest monsoon summer in Tucson history! (Plot: National Weather Service)

While the Autumnal Equinox is a pretty neat phenomena that can be explained by any Astronomy graduate student at Steward Observatory, we have an additional event deserving a celebration: today is the 5th year anniversary of the arrival of the CACTI testbed in the XWCL!

For the uninitiated, CACTI stands for Comprehensive Adaptive optics and Coronagraph Test Instrument. CACTI is XWCL’s AO simulator testbed where we can tack on and swap components for testing and developing projects (particularly for many of XWCL’s optics graduate students’ PhD dissertations).The initial incarnation of CACTI was used to develop Kelsey’s dissertation on Linear Dark Field Control. The current version of CACTI began as the AO simulator of Lauren’s 3PyWFS dissertation project. At the moment, CACTI is serving several projects such as my laboratory demonstration for a cubesat laser guide star, Alex R’s demo of the differential Optical Transfer Function WFS, Sebastiaan and Meghan’s optical differential wavefront sensor, and Avalon’s Basler camera characterization. CACTI has endless capabilities, with only physical space and laboratory time as the limits.

To celebrate CACTI’s 5 year anniversary, let’s take a walk down memory lane to see CACTI’s evolution.

The CACTI table was moved from room N431 to the XWCL space in room 265. It was this instance where we learned we could not use regular movers for relocating an optical table. Instead, we required riggers who have access to a crane to lift and move the optical table. Though Jared was absent for much of the moving process picking up a pallet with Alex R, Dr. Kelsey Miller was able to record some of the process.

Sept 22, 2016: CACTI now in 265, horray! (Photo: Dr. Kelsey Miller)

To prepare CACTI’s table placement, we used masking tape to set up locations where the table legs would be positioned such that the table would be balanced when craned down. However, no matter how well we measured and allocated tolerance regions, some table legs needed to go elsewhere.

Sept 22, 2016: A legend in the making, never to be forgotten.

These days, when you walk into XWCL, it’s packed to the brim. Some walking areas are only wide enough for a computer rack to pass through. It’s hard to believe that once upon a time, the XWCL consisted of the CACTI optical table, a few desks, and a bunch of shelves. It was also a time when Beast still did stuff.

Over the course of a year, the XWCL room started filling up more and more. This includes CACTI’s journey of upgrades. The first major CACTI facelift was the BMC 1K’s new air pressure chamber. Justin worked diligently through many different designs. The first prototype was a tupperware with a hole cut out for a window chamber. It eventually converged to the current chamber, custom built with holes for cable routing and an entrance for pumping in dry air.

In summer 2017, CACTI was graced with a new addition: the Zygo Verifire Fizeau interferometer. It was promptly parked onto CACTI, along with the first and only Windows machine in XWCL.

June 27, 2017: The Zygo Verifire is free for use for all CAAO-related projects.

The Zygo Verifire has been an interesting learning experience. Beyond measuring and characterizing deformable mirrors, flat mirrors, and various LBTI hardware, it has bricked twice. Alex R and I tried to hook up the Zygo computer to the internet, only to brick the software because the ethernet port was for communicating between the interferometer and computer. We spent 2 hours on the phone with a Zygo engineer, who eventually stepped us through fixing the settings so we could connect the Zygo computer to the internet. Kyle, Kelsey, and I discovered together one afternoon that the Zygo uses Basler cameras. We installed our Basler cameras’ software on the Zygo machine, only for the software to stop working because the installation overwrote the required Zygo version. Luckily, we were able to revert to a recent, old Windows version state and undo our errors. Despite these unexpected inconveniences, the Zygo Verifire has been the backbone to very important work.

Sept 20, 2017: How to fix the Zygo. (Photo: Alex Rodack)

Soon enough, a new neighbor moved in next to CACTI: MagAO-X! After passing PDR in May 2017, MagAO-X began building in XWCL. The first thing assembled was the portable clean room, which arrived in July 2017.

July 26, 2017: Alex R (left) and Dr. Kelsey Miller (right) showcasing the newly built portable clean room. (Photo: Dr. Jared Males)

The arrival of the clean room meant moving furniture around in the lab.

July 14, 2017: Dr. Justin Knight shows us there is plenty of space behind the shelves for storage. (Photo: Alex Rodack)

From the get-go, the MagAO-X cleanroom was designed for portability that could fit above CACTI with minimal fuss. Early on, we identified the air ducts and lights needed to be moved and replaced so the clean room can properly fit above CACTI. That was something that got fixed.

The next major CACTI upgrade was installing blackout curtains around the table. This helps considerably when an experiment is light sensitive. The curtains have allowed simultaneous non-CACTI laboratory work with the ceiling lights on while minimizing external source disturbance during data collection. Along the way, we learned that a top curtain was essential for an occasional ceiling pipe leak. We store all the DM drivers at the top shelf that a water leak on these electronics will destroy them. These electronics are not easily replaceable, particularly the IrisAO driver!

Oct 20, 2017: MagAO-X cleanroom with legs in foreground, CACTI with full blackout curtains in background.
Nov 14, 2019: Two years later, the air duct construction has its moment to shine. The adjusted ducts and lights, and the cleanroom moved over CACTI while MagAO-X and the team are in Chile. (Photo: Alex Rodack)

In 2019, Lauren and I designed an upgraded CACTI with custom lambda/10 OAP mirrors. In December 2019, we received the new OAPs and dismantled the original CACTI. We began building the new CACTI in January 2020. However, the pandemic hit halfway through our build process. Nevertheless, Lauren heroically trucked on and completed building CACTI in summer 2020 just in time to integrate the 3PyWFS from HartSci. In May 2021, Dr. Lauren Schatz finished her PhD using CACTI and the 3PyWFS was shipped out a month later.

Sept. 22, 2021: CACTI in its current form

CACTI continues to get lots of action in the lab. Open spaces on the testbed get used for small testing experiments. I’ve since added a secondary source to CACTI for my laboratory demonstration of LGS. Alex R and I have worked out a procedure for swapping the IrisAO segmented DM in and out of a pupil plane that can be done solo in less than 1 hour. Joseph, Lauren, and I wrote CACTI’s testbed operation entry in the MagAO-X handbook as a localized resource for users, to which I update regularly. Since CACTI utilizes a customized version of the MagAO-X control code, it also has the capability of being operated remotely. There are a few limitations though, such as the IrisAO DM driver power button requiring a physical button push.

Despite XWCL and CACTI’s evolution through the years, there remains one constant: the masking tape continues to hang out underneath the table leg.

Sept. 22, 2021: Masking tape under CACTI table leg. The excess has been cut off since the fateful placement 5 years ago, but it’s still there if you look closely.

Happy 5th anniversary, CACTI! Here’s to many more years of new development, more dissertations to feed into, and everlasting masking tape under the table legs.

With lots of love,

Jhen and Alex R

Song of the day

Given the focus on the desert (CACTI,  rain, and Tucson), and our love for a connection to space/astronomy, we pick a song by Tucson’s own Calexico, who have been making their unique brand of “desert noir” rock since the mid 90’s. This particular song was picked by Rep. Gabby Giffords to be played in space on June 13, 2008, on the Space Shuttle Discovery as the wake up call for the crew including her husband (and current AZ Senator) Mark Kelly.

Calexico, “Crystal Frontier”

And let us never forget, at XWCL,

The XWCL motto