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Ten things to know about being on co-op at the world’s largest particle physics laboratory

Meet Katie Larkin, Jameson O’Reilly, and Preston Epps. Three fourth year students who spent the last six months living and working abroad at one of the world’s largest centers for scientific research – the European Organization for Nuclear Research in Geneva, Switzerland, more commonly known as CERN. Home to the largest particle physics laboratory composed of gigantic particle accelerators and detectors and many other instruments, CERN focuses much of its research on understanding fundamental particles and the forces that hold them together. These are the tiniest pieces that make up all matter – everything in the universe. With over 10,000 scientists from more than 100 nationalities, CERN is a place of true collaboration and diversity with a common goal in mind to further human knowledge.  For Northeastern’s three spring 2017 co-ops, this was an opportunity of a lifetime, and a long-time dream for them.

Why did you want to work at CERN?

For physics and math combined majors O’Reilly and Epps, they’ve been dreaming of working at CERN since high school.

“In physics, it’s kind of like the mecca for us,” Epps said. “I remember being so excited the day they discovered the Higgs Boson particle at CERN. I ran around to tell everyone I knew. It’s always been the place in my mind for particle physics.”

O’Reilly agreed.

“It’s this incredible place where thousands of people are doing thousands of amazing things,” he said. “It’s just wild. Part of the reason I chose to come to Northeastern was because I knew this co-op existed.”

For Larkin, her experience was a little bit different. As a biomedical physics major hoping to delve into a career in science policy, she was excited to get excellent research experience but also the privilege to work at a science collaboration like CERN, in Geneva, a center for diplomacy and incredible science all at once.

What did you do while on co-op at CERN?

While it was unusual for Northeastern to send three co-op students to CERN all at once, all three of them had unique experiences and were able to work on different projects.

Epps focused on the data quality monitoring (DQM) software that monitored the live feed of data from the compact muon solenoid (CMS) detector. His work involved updating as well as identifying specific data anomalies that occurred.

Larkin’s work was also software based. She spent much of her time programming software for an adaptor to test prototype electronics, the final version of which will be used on the Electromagnetic Calorimeter (ECAL) sub-detector. She and her team built the adaptor to compare the existing and prototype electronics during test beam runs. This was important to work properly before all updates were established, as well as to help with quality control for the test beams being run with prototypes.

On the other side of things, O’Reilly’s work was much more hands-on. He built and tested prototype miniature cathode strip chambers, or miniCSCs. Cathode strip chambers, a type of muon detector with gas inside. The gas molecules in the chamber are ionized by passing particles, which causes the molecules to lose an electron and then gives coordinates for each particle. Some CSCs contain greenhouse gases which help chambers last longer during this process. However, since greenhouse gases are harmful, O’Reilly worked on creating and testing prototypes that utilize different gas mixtures to find something that could work as well or better than the greenhouse gases do.

O’Reilly cleaning cathode panels. Photo courtesy of Jameson O’Reilly.

What is happening to these projects now? 

O’Reilly’s work is continuing at CERN with the help of graduate students there that he helped to train at the end of his co-op. Additionally, he received an undergraduate research grant to work on an extension of the project remotely at Northeastern. He’s created virtual chambers which simulate different gases, testing their abilities before trying them on one of only six created prototypes.

Back at CERN, their current co-op Kelsey Yee has continued to work on a variation of Larkin’s project analyzing the data from the test beam runs.

The Northeastern collaborations at CERN are run by principle investigators and Northeastern physics professors Toyoko Orimoto, Darien Wood, and Emanuela Barberis.

What is it like to work at a such an international center for research in physics? 

In talking to all three students, they agreed that it took some adjusting to work at such a large, international collaboration, especially in terms of communication.

“In the global aspect, the official working languages of CERN are French and English, but most people seemed to speak English and not French,” O’Reilly explained. “My main boss was Italian, and I worked with a lot of Russian scientists, some Chinese technicians, and a Czech graduate student. When they’d see each other, they’d speak their shared languages, and I’d wait for them to finish. It was difficult to communicate sometimes but it forced you to be very clear and intentional because you can’t assume people understood.”

Aside from language, with CERN being such a large hub for science and research, they often hosted colloquiums and speakers on a variety of topics – everything from an astronaut’s experience on the space station to a physicist’s plan for a new linear collider. Larkin attended many talks during her time there and it became one of the most interesting parts of her job.

On a large campus with over 300 buildings, the co-ops also had to adjust to learn their way around and figure out where they were going.

“All the buildings were numbered but it took me about five months to learn my way around. It was only a ten-minute walk from the bus stop to our offices, but for the first week we took a different route every time on the way there and back,” Larkin recalled.

Epps commented on his surprise of the campus as well.

“I was expecting a futuristic, high-tech research center, but it’s mostly old, 1960’s style architecture complete with sheet metal shacks and countless random statues,” he said, laughing.

View outside the window of Larkin’s building at CERN. Photo courtesy of Katie Larkin.

What was life like outside of work?

The US CMS provided free housing for Epps, Larkin, and O’Reilly, less than 20 minutes away from the CERN campus. Epps and Larkin lived together in an apartment in Ferney-Voltaire, a small town just over the Swiss border, in France. O’Reilly lived a few towns over in the CERN US-CMS house with several graduate student colleagues, in Saint-Genis-Pouilly. Their daily route to work took them right past the Geneva airport, making it easy for weekend trips to countries all over Europe.

The three friends travelled to an endless list of cities and over 12 countries, with each other, on their own, and with other friends studying abroad around Europe.

What was your favorite place to travel to?

“I think my favorite cities were Rome and London,” O’Reilly recalled. “But my favorite trip was actually with two of my Boston roommates. We went up to a cabin in the Alps, right on the side of the mountain, and got to spend the whole day hiking through the Alps.”

Larkin enjoyed doing some travelling on her own.

“I went to Lucerne in Switzerland for a concert, and then went to Dublin for the rest of the weekend, and that was such a cool trip,” she said.

“My favorite place was all of Italy – all of the experiences were amazing, and I’ll always remember some really good times together,” Epps added.

How did this co-op play into your future career plans?

The experience of working at CERN alongside brilliant scientists from around the world helped the co-ops to gain some insight in what they want to see in their futures. O’Reilly knew before he started that he wants to be a research scientist/physicist, and this co-op helped to confirm it.

“It really increased my confidence to be an independent researcher,” he said. “The project wasn’t my idea, but I had a lot of responsibility and ownership of it, and now I feel more gung-ho about things like that.”

How has this co-op helped you now that you’re back in classes?

Larkin was able to connect her future career path in science and health policy to the co-op with the many colloquiums she attended at CERN. She learned about medical applications of the electronic calorimeter that she worked on, whose applications for radiology equipment is being discussed in one of her classes now.

She and O’Reilly also reflected on the skills this co-op helped them develop, which will help them in the rest of their Northeastern career and beyond.

“It’s a collaboration, you really can’t do any part of this on your own, and so I do think it’s helped my ability to set up meetings, work well on homework or projects with a group of people,” O’Reilly said. “These soft scientific skills are so essential.”

View from the top of mountain in Alps. Photo courtesy of Jameson O’Reilly.

What advice would you give to someone working at CERN?

O’Reilly learned a lot from this experience, and continues to work for CERN remotely with Northeastern professors. His time there helped to drive his future in physics research, and he strongly recommends this co-op to anyone at all curious.

“It’s most important to fully engage with what’s given to you,” he said. “Go to as many seminars as you can, go to as many countries as you can, and do as much work as you can while still enjoying yourself. There is a huge amount to do and digest, but that only matters if you make use of it all.”


This work was largely funded by the National Science Foundation grants PHY-1120138, PHY-1624356, and PHY-1343486.

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