Experimental Particle Physicist | Deutsches Elektronen Synchrotron (DESY)
Can you describe your role as an Experimental Particle Physicist?
I work in a German laboratory called Deutsches Elektronen-Synchrotron (DESY), and I am a member of the ATLAS Collaboration, which is a big experiment at the Large Hadron Collider, a complex accelerator built by the European Organization for Nuclear Research (CERN). The ATLAS experiment is a giant particle detector located 100 meters underground near Geneva in which accelerated particles collide at its center. Currently, I am involved in data analysis of the information collected by the detector.
I am also working on the detector development for a new sub-detector, which will be installed in 2026. In the future, the particle collisions will be more violent (more energetic), so we need to increase the potential of the machine and some parts of the detector need to be rebuilt. The research and development (R&D) and soon-to-be production of a sub-detector are performed at DESY.
Can you further explain CERNand the ATLAS Collaboration to our readers?
The ATLAS Collaboration is one of the biggest collaborations in the world. We are about 3000 scientists working together on detector operation, data analysis and writing papers. In our day-to-day life we are divided into sub-groups that have several different missions. I am working on data analysis in which we try to see patterns in the data using algorithms in order to validate or invalidate models. Ultimately, we are building the textbooks of tomorrow.
When it comes to hardware, we are building a new part of the particle detector by upgrading the tracking detector that records all the traces when the particles come through in a collision. During the R&D phase, we make sure the new technology of particle tracking detectors is able to detect all particles, so it has to cover all directions ( it requires thus a large surface of silicon sensors) while ensuring the detector is not damaged, nor overheats by the higher collision rates. There are many groups working on this, and DESY is strongly involved in this project. I try to switch between software and hardware which isn’t easy, but both are very interesting.
What made you choose this field of work?
I am very enthusiastic and that is part of my personality. This is emphasized by how I found a field that is feeding me.
It started from my enhanced curiosity. When I was in high school I didn’t know what I wanted to do later on (at one point I wanted to be a car designer). I worked hard to have good grades, but I also had intrinsic questions for my science teachers, and I was never happy with their answers. My mom learned about scientific work camps, so I ended up at a summer camp in France where I talked about mathematics and science until 3 AM with people of my age who were also fascinated by these questions. I realized it was possible to be interested by what we learn at school the way some are interested in soccer, or horseback riding. I could have easily missed this by being uncomfortable and not knowing that some people were passionate about topics taught at school such as physics, math, biology.
Can you tell us about your STEM career so far?
I went to the Engineering school of Applied Physics in Toulouse (INSA). My parents also pushed me in the direction of becoming an Engineer so that I could earn a degree that can ensure a living. I was fascinated by the leading-edge technology of particle detectors but wanted to know more of the fundamental science. As my engineering school had no particle physics courses, I negotiated to study particle physics in Germany, where I did an exchange program during one semester at Humboldt University in Berlin and with DESY at their campus nearby in Zeuthen.
I adored this work and it enlightened me; I really like the equations and working on challenges that are fascinatingly precise and yet not resolved yet. There are some caveats of being on the cliff of knowledge; at times it is not so comfortable. Yet it is exciting to work toward learning something that no one else knows yet.
One day I saw a plot of a cascade of particles on a scientist’s screen and asked him a lot of questions. He was busy, so he said that if I wanted to understand the plots I would have to get a PhD. I don’t think he realized that I took him literally. I finished my degree with a Master’s in Engineering with an Instrumentation specialty, which is very technical, but I knew that after graduating I would do another degree in fundamental science.
My engineering program required students to complete an internship during the last semester. I wanted to discover North America, and that’s how I found TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, where I started working on a side project for the ATLAS detector. The internship was meant to last five months in Canada, but my supervisor offered me a PhD position at the University of Victoria, so I stayed in Canada for another five years. In the middle of my graduate studies, I went to CERN to do my qualification task (overseeing a sub detector to make sure it ran smoothly). I finished my PhD in 2016 and started applying for jobs and was offered a fellowship at DESY where I could choose what to work on. I voted to stay in the ATLAS Collaboration and joined the detector development effort and an analysis team.
What keeps you motivated?
I like the adventurous part of academics, but it’s not like this every day. There are moments when you don’t know what you’re doing, but with research you have to be comfortable with not knowing all the answers. It’s a field that is high-paced and there are lots of expectations. Perhaps, the expectations are high due to the competition and also because of your own self, as curious and enthusiastic. One has to find a balance. I always ask myself: what would be good for me as a scientist? and as a human being?
How does your field of work intersect with foreign policy?
CERN is one of Europe's first joint ventures and now has 22 member states. Particle physics, in a sense, has nothing to do with foreign policy. Particle physics studies how matter’s most basics components interact, and the nature of them does not depend on humans or our moods. The laws of physics are the laws of physics. However, for making scientific advances the field brings many very diverse human beings, who gather despite ongoing political issues to do science, and that’s where international cooperation exists.
How do you collaborate with people from different countries?
The physics we do is independent and not biased by who we are; however, when we calculate some entities like the rate of particle decay, for example, different scientists from several countries come together. Some are upper-class and some lower-class, some religious and some not, but these features do not play a role. We discuss for instance how to calibrate the energy of an electron. It’s amazing to see how physics unites and builds upon diversity. I get to meet interesting people from different backgrounds and we build knowledge together. Working in a diverse collaboration helps each member be more open minded.
Sometimes cultural differences are present, and we learn more about them after spending some time in the field. For example, Germans tend to be more organized, Americans exhibit more confidence in meetings. But the collaboration is centered on science. In the end, we are people coming together from different backgrounds and countries to contribute to scientific advancement.This puts us in a horizontal level in which we are all equal as collaborators. The differences that we bring are a nice mixture, but they are not obstacles to doing science.
There’s evidence that there aren’t as many women in STEM. Can you tell us about your experience as a woman in this field?
The fact that there aren’t many women in STEM isn’t where the problem lies; the problem is when women are prevented or discouraged from doing what they are interested in because of bad cultural templates or biases. Even if there are lower numbers of women, I have never felt degraded or diminished. I feel a lot of support.
Within my collaboration, there are several subgroups. Some have 40% women and others with different scientific activity have much less women, so representation in subgroups varies. At the moment, there are also quotas for job openings, which means that if male and female candidates are both qualifying for the job the women will be favored to correct for previous discrimination. This is incredibly influential, but some people say it’s unfair. It’s a bit controversial and I have mixed feelings about it, but it’s good that people are trying to address this problem and that an effort is being made.
What advice would you give to young women hoping to work in STEM?
I do worry that some remarks based on gender will discourage children in this field, either women fearing to take jobs in STEM or men fearing to take jobs they see as a woman’s job. I ask myself: How much brilliance are we losing along the way due to gender conventions? Sometimes we can kill a career by words and that’s a pity. We need to constantly be alert to such remarks and be ready to react.
My advice to all is to follow your interests. If you are uncomfortable with not knowing, it’s a good start because following your curiosity and interest is what you should do. If I had known all the difficulties ahead when I started in academics I probably would not have started at all. Do not worry about how competitive a field is, just focus on what is fun and cool to investigate.