6 views of working in particle physics without a PhD

How long have you been at Fermilab?

I’m still very new actually; I started my position in early July of 2021, so it’s just over a year. I’ve had a lot of colleagues at Fermilab with whom I had collaborated or interacted scientifically going back for quite a while. I was accustomed to visiting the lab, but as a formal employee, I’m still pretty new.

Can you describe what you do and what you work on at Fermilab?

I’m a staff physicist. I wear a number of different hats. I’m a theoretical physicist, and I do a lot of computation as well. The main bread and butter of what I do at Fermilab is related to the neutrino program; doing theory calculations that are relevant for neutrino nuclear cross sections and understanding aspects of those calculations in greater detail and in preparation for the DUNE program. Much of this work depends on my core efforts to understand the strong interaction—one of the four known fundamental forces in nature—with greater accuracy at both high and low energies.

Another aspect of it is computational, as I was hired in part to provide guidance to the GENIE event generator framework, which is a necessary tool that experimentalists use to make predictions for experiments and calibration and that sort of thing. A lot of what I do stems from my background in quantum chromodynamics. The idea is to try and control the neutrino nuclear scattering cross section to better accuracy and precision.

I also have some activity in the Fermi Quantum Institute. The idea there is to perform simulations of nuclear systems in service of the neutrino program. A lot of the work is still very new, so it’s very exploratory to try and identify what you can even do in principle with machines like this. There’s a lot of just trying to formulate things with simple models or simple theoretical setups. My home is in the scientific computing division, but I’m also a presence in the theory division and then in FQI; I bring together a number of different threads at the lab in that respect.

How did you first get interested in pursuing physics?

I think some part of me was always drawn to things that seem deeper. I always wanted to have a more fundamental understanding of things, to tear the wallpaper down and see what’s underneath. I searched around for quite a while, especially when I was younger. It seemed like I kept coming back to physics and trying to understand matter and energy and time and these really fundamental things. I think I was in the fifth grade was when I learned what a physicist was, and I was like, “This is what I want to do.” I really feel an enormous amount of gratitude and good fortune just to be able to do this because it’s what I’ve wanted to do for so long.

What is the most rewarding part of your job?

People have thought about these sorts of things for thousands of years, but to get a sense that you can actually do something; you don’t get that in a lot of other areas of human thought. I also find really gratifying the fact that there’s a conclusion or some sense of progress. You learn more and you grow your knowledge. Cumulatively, we’re also learning more, and I think that’s really exciting and really cool.

Is there anything you find particularly challenging about your work?

One thing that’s challenging—really with any complicated undertaking—is getting a bunch of people on the same page intellectually. Different people have different expertise, and so we all have to coordinate collectively in some way. Some people are particularly good at developing a certain type of algorithm, and you need input from theorists. Then we need our experimental colleagues to have a lot of input. Part of my job is to bring many of these different people together, but the work of collaboration, which is its own reward, is something that requires a lot of effort to nurture.

What do you like best about working at Fermilab?

I think Fermilab really makes an effort on a number of different fronts to have an inclusive culture. I do get the sense that, of the number of different places I’ve been, it really cares [about] trying to do the right thing. I really get the sense that the lab tries to prioritize making employees feel cared for or taken care of. It feels like an open and generally welcoming place.

What do you like to do for fun?

My job consists of reading a lot of physics papers, so I like to read things that aren’t physics. I definitely enjoy cooking, and more importantly, eating. I also really like traveling internationally, which has been kind of hard during COVID. Eating new food, meeting new people and hearing different languages, that all really speaks to my heart.

Fermi National Accelerator Laboratory is supported by the Office of Science of the U.S. Department of Energy. The Office of Science is the single largest supporter of basic research in the physical sciences in the United States and is working to address some of the most pressing challenges of our time. For more information, please visit science.energy.gov.

 

Cryomodules are essential components for the U.S. Department of Energy’s Fermi National Accelerator Laboratory’s accelerator complex upgrade, known as the Proton Improvement Plan II, or PIP-II.

PIP-II features a brand-new, 800-million-electronvolt leading-edge superconducting radio-frequency linear accelerator, or linac for short, that will enable Fermilab to produce more than 1 megawatt of beam power, 60% higher than current capabilities. To achieve this groundbreaking feat, the linac will be made up of cryomodules, which are vessels containing niobium cavities.

The first particle accelerator on U.S. soil built with significant contributions from international partners, PIP-II will receive three assembled cryomodules from partners at the Science and Technology Facilities Council in the United Kingdom and nine assembled cryomodules from Commissariat à l’Énergie Atomique et aux Énergies Alternatives, or CEA, in France.

Safely transporting these delicate and expensive assembled components to Fermilab will be a major challenge for the PIP-II team. Based on a recent experience where a cryomodule for another experiment was damaged in transit, the team is taking extra precautions to ensure the safe transportation of PIP-II’s cryomodules, including extensive tests of the transportation system.

The first step was to design, build and test a transportation frame that will hold and protect the cryomodules. While PIP-II collaborators at STFC—and later, CEA—will eventually design and build their own frame, a prototype of the STFC frame was built at Fermilab where it will be used to ship a dummy load and prototype cryomodules. This design and validation are a team effort between the three labs, with the results and lessons learned influencing the design of the final shipping frames that will transport the production cryomodules from STFC and CEA to Fermilab.

“The whole project is working as one to [achieve] one approach for transport,” said Jeremiah Holzbauer, a Fermilab scientist in the PIP-II Technical Integration Office. “We’re all learning through this first process together.”

Mitchell Kane, a mechanical project engineer at STFC, designed the test frame in close collaboration with Fermilab, who then hired a U.S. company to build the frame.

The most difficult part of the process, Kane said, was that there isn’t yet a finalized design for the cryomodule that the frame will eventually hold. “You have to have some flexibility in the design. With flexibility, there’s uncertainty,” said Kane.

The Fermilab team fabricated a dummy load to be a replica of the cryomodule—essentially, concrete blocks with the dimensions, weight and mounting points of the cryomodule. They then demonstrated the complex installation of the dummy load into the test frame and prepared it for transportation tests.

For now, the test frame assembly is an example of the successful collaboration of an international team—hopefully, one of many triumphs to come for PIP-II.

“We were able to actually have a pretty flawless first-time around of setting this thing up,” said Ryan Thiede, technical specialist for cryomodule assembly. “It turned out pretty well. Everything lined up. We had very few problems, and it seemed like everybody was pretty impressed with the first go-around of the setup.”

Kane visited Fermilab in late April to oversee the frame assembly and dummy load test. “Because of COVID and everything, I hadn’t seen anything physically for two-and-a-half years. So actually going there and seeing my design in person and it actually [going] together without any problems was probably the best [part of this experience],” he said.

On April 25, the test frame endured a three-hour highway road test to check the performance of the isolation system, which is designed to cushion the ride of the cryomodule. “It went extremely smoothly. The design is quite good,” said Holzbauer.

This summer, the test frame holding the dummy load will be shipped to the UK where STFC technicians will disassemble it, put it back together and ship it back to Fermilab. This process will also check the transport logistics, such as customs inspections and airplane loading.

“If that goes successfully, the transport system is verified,” said Holzbauer.

Next, PIP-II will use the frame to ship a prototype cryomodule to the UK, which is currently planned for the end of this year. Once there, PIP-II partners at STFC will unload the prototype cryomodule and take it through instrumentation and vacuum checks before sending it back to Fermilab.

“Once it’s shipped back to us, we’ll test it again and make sure it really still performs as well as it did,” said Holzbauer. “That’s the ultimate proof that we can ship cryomodules. And that basically is the core demonstration [that] we can ship all of our cryomodules.”

Finally, in a few years’ time, the STFC will ship the production cryomodules in their own refined version of the shipping frame to Fermilab for the construction of PIP-II. Kane said they have already noted some small tweaks in the design that they’ll make to the UK frame.

Then, in 2025, it will be CEA’s turn to put their own transportation frame to use. Once production begins, the French collaborators plan to ship cryomodules to Fermilab at a pace of one per month.

Robin Cubizolles, an engineer at CEA and a PIP-II sub-project coordinator for cryomodules and transportation, observed the procedures for the assembly and design of this test frame and said he learned a lot that he will inform the CEA transportation system.

“I want to thank Fermilab for the good collaboration. [There is] a lot of transparency in every aspect,” said Cubizolles. “For me, it’s my first project with this kind of [collaborative working arrangement], and it’s really nice to see that.”

For now, the test frame assembly is an example of the successful collaboration of an international team—hopefully, one of many triumphs to come for PIP-II.

“Working between the technical team here like myself, the instrumentation people here and the partners both at CEA and STFC, I think we made a lot of very good design changes in the pre-planning stage,” said Holzbauer. “We got a lot of our procedures really in line, really vetted, and all the specifications were very clean. They helped us with vendor oversight. And so that all built up to today, when we all came together real smoothly, really clean, very safely, and it all went exactly like we wanted it.”

Fermi National Accelerator Laboratory is supported by the Office of Science of the U.S. Department of Energy. The Office of Science is the single largest supporter of basic research in the physical sciences in the United States and is working to address some of the most pressing challenges of our time. For more information, please visit science.energy.gov.