Category: MagAO-X

Hello from Arizonans in California! I just got back from the UC Santa Cruz Center for Adaptive Optics (CfAO) Fall retreat, where members of the AO work through some of the pressing problems in the field. This year was focused on High Contrast imaging testbeds, lessons learned from Magellan’s MagAO-X and Subaru’s SCExAO and what might be in the cards for Keck, and a round up of adaptive Secondary progress – LBTO, MMT, and the future of IRTF, KECK, and beyond.

Some of the likely suspects were around, namely Jacob and Robin from UToronto representing MMT calibration work and Sam Ragland from LBTO operations. Thanks to a very generous student scholarship from the workshop organizers, I was able to attend and represent MagAO-X’s progress.

Sam’s update on the LBT’s progress was some of the most concrete work concerning a long-term Facility adaptive secondary, in this case using adOptica technology. Sam discussed the re-coating of the secondary, and future plans, including adopting an ASM from CHile, close to this group’s heart.

Jacob got the longest student talk of the conference, and got to spend an hour discussing his method for calibrating on sky. A key difference between the LBTO and other telescopes discussed being that LBTO is a Gregorian design with an intermediate focus that allows for daytime calibrations of their secondary. MAPS and systems like IRTF and Keck are Cassegrain design with no focuses before the primary, and can only take calibration matrices on a bright star on sky. Making the operating software and calibration procedure robust in the meantime is a huge step towards making these systems reliable and facility class.

We also got one last GMT talk from Antonin, who has recently moved from his role on GMT to the AO scientist for the Keck twin 10ms. He gave an update on the current design of the GMT adaptive secondaries, which will be using a similar technology to what’s currently on LBT. In fact, we learned that the rigorous modeling and testing on the GMT prototypes solved a resonance issue that LBT had unexplained.

I cannot express how grateful I am to have a community that shares and collaborates as this one does. Even though MagAO-X is already built, there’s a lot to learn from the discussions that Keck is having about their own testbed. As in, what areas of interest are already met by our technology? What new avenues are being pursued? And where do all fit in the the US high contrast family?

Thank you to everyone who made this conference so fruitful! And to the organizing committee for the student scholarship.

Song of the Day

I suspect all of our readers will be aware that last Saturday there was an eclipse event over the US. At 9:30 am Tucson Time was the peak of the annular eclipse, an eclipse where the moon is at the furthest point on its orbit, called apogee, so the disk of the moon is a smaller angular size on the sky than the sun (where normally they are essentially the same size) so it doesn’t block the whole disk and you can’t see the corona. Instead you get a “ring of fire” caused by the moon’s antumbra on the Earth’s surface.

Tucson was not in the area of max shadow, it only got about 80% coverage. So some XWCL members traveled to regions getting the full antumbra effect.

I met up with XWCL alum Lauren Schatz and UA OpSci grad Silvana Ovaitt. When Lauren was at XWCL she was my hiking and camping buddy, so we reunited for more L&L adventures by camping in Monument Valley Navajo Tribal Park!

We also went on a backcountry guided tour off the public access road and led by a local named Larry

Song of the day is Black Hole Sun by Soundgarden.

Back in Tucson the XWCL team has been very busy hosting some exciting visitors! Teams from the Giant Magellan Telescope Organization and the Arcetri Astrophysical Observatory made their way down south to integrate a natural guide star wavefront sensor prototype (NGWS-P) with HCAT and MagAO-X. To put it simply:

“The Giant Magellan Telescope (GMT) Adaptive Optics (AO) systems feature a single conjugate natural guide star based AO system using the 7 deformable secondaries and a post focal wavefront sensor named NGWS (Natural Guide star Wavefront Sensor). The NGWS has two different channels: one featuring a high spatial sampling pyramid sensor dedicated to the fast frame rate correction of atmospheric turbulence and a second dedicated to the correct phasing of the 7 segments of the GMT telescope.”

Plantet, et al., SPIE Montréal 2022

Essentially, they want to use our GMT simulator (HCAT), and functioning ExAO system (MagAO-X) to validate their prototype wavefront sensing channel (PyWFS) and prototype phasing channel (HDFS).

I want to impress on everyone reading this blog what a complicated setup this actually is. We are simulating the GMT on the HCAT testbed, feeding the GMT pupil into MagAO-X through a hole in a wall, and feeding the NGWS-P testbed through the MagAO-X eyepiece. That is not easy to do…but we did it!

The team started by using the HCAT lab as a staging area where the teams could integrate the two channels onto the NGWS-P bench. Laird and I were busy inventing new novel optomechanical mounting strategies (AKA zip tying a camera to a ladder) so we could view the focal plane the NGWS-P will be receiving.

Once the dress rehearsal was over, we rolled the NGWS-P into the MagAO-X lab and the team went quickly into alignment.

As the life-long learners we are, when plugging in the NGWS-P cryocooler we unfortunately tripped a circuit breaker and MagAO-X went dark. Duh, duh, duh…Luckily we called our most recent alum Dr. Joseph Long to the rescue!

Don’t worry, it’s all fine. We learned the lesson: if you ever want to force-quit MagAO-X, simply plug in a cryocooler on the same circuit.

The software gurus started to make some quick progress once the whole system was finally in place. Alfio (Arcetri) and William (GMT) were poking away at the MagAO-X DMs using their own wavefront sensor.

Ultimately they were able to close the loop using the NGWS-P modulated PyWFS and the MagAO-X Woofer DM with 30 modes! This was a fantastic first run and there is much more exciting work to be done in our subsequent two runs coming this fall. Looking at you parallel DM.

Sharing this musical experience that the GMT, Arcetri, and Arizona teams got to enjoy at Hotel Congress last Friday evening.