My experiences in 3 different nuclear laboratories across the world.

by David Godos Valencia

​In this post, I would like to tell you about my involvement in different Nuclear Physics Laboratories in the US and Europe during my Ph.D.. Even if an experimental path is not your focus, chances are high that you will visit at least one of these facilities during your career. These times can be extremely nurturing, as you can learn on the spot from all the people involved in the laboratory, such as technicians, researchers, and other students. Furthermore, while participating in an experiment during your visit, you will be granted a wide view of how Nuclear Physics research is conducted, the standards it must meet, and the challenges that could arise during the measurements. In that sense, I consider that it is also quite important for everyone, especially those working in theory, to understand the entire process of data acquisition. Particularly, in this post, I would like to share my experiences at the Nuclear Science Laboratory at the University of Notre Dame (Indiana, USA), ISOLDE at CERN (Geneva, Switzerland), and GANIL (Caen, France) [1-3].
Starting from 2022, just after the pandemic, I have had the opportunity to collaborate with researchers of the University of Notre Dame’s Nuclear Science Laboratory (NSL) at South Bend, Indiana, USA. The international collaboration I was in was quite diverse and consisted of people from Italy, Greece, Mexico, Portugal, and the US, among other countries. My participation was made possible through my advisor’s project funding. As a student, I was invited to gain experience with the detection setup, and the electronics that connect the detectors with the pre-amplifiers, amplifiers, and finally to the data acquisition system, for the TriSol separator.  I was quite excited because we were working with Double-Sided Silicon Strip Detectors (DSSSD), as in my Ph.D. project. 
That was my first time in a US laboratory, and I couldn’t help but spend as much time there as possible. While working with the setup, we arrived before the beam was delivered and spent days and nights optimizing the configuration of the electronic chain. I gained more practical skills during those weeks than in an entire semester! Before leaving, I also took part in a night shift. They are usually quite calm, but you never know what might happen in one shift. Some examples are: losing the beam, and then calling the operators back, or the target being damaged during a test.
I loved the University of Notre Dame campus, which is full of life even at night, with visits from rabbits and even deer. The following year, in 2023, I returned to participate in another measurement at NSL, and in 2024, I was awarded the IReNA Visiting Fellowship, which supported an 8-week internship at the laboratory. I made the most of that time by collaborating on experiments, gaining practical skills in the laboratory, and advancing the analysis of previous experiments carried out at TriSol.

​Picture 1. Selfie while working at Notre Dame’s Nuclear Science Laboratory (NSL) during the IReNA Visiting Fellowship program.

​Just last year, in 2024, I had the chance to participate in a measurement at the Isotope Separator On Line DEvice (ISOLDE) at CERN. Never in my life had I imagined visiting CERN under such circumstances. Just to be able to assist at the site, you must first affiliate yourself with CERN via a team leader of a partner institution and complete the required online security courses, which cover emergency procedures and safety protocols. In addition, some on-site courses are necessary if you wish to access the beamline. During my stay, alongside other students, I completed the electrical and radiation safety on-site courses, which gave us authorization to access the detection setup.
Once I arrived for the first time there, I had to present myself at the visitors’ office to get my badge so I could access all sites where I had authorization. In some cases, particularly if you need to work close to the beam line, it is mandatory to have a dosimeter for measuring the radiation exposure during your visit. Accommodation is available at the CERN hotel on the Swiss side of campus, though during busy experimental seasons, there may be no room availability. I remember having to switch to a shared room mid-stay. There is also a large restaurant near the hotel with a lot of delicious food, though one must be prepared to pay as in Switzerland; it’s not cheap. Nevertheless, you can also take the bus or a rental car to travel to nearby French restaurants. My experience there was spectacular, and I hope to get back soon.
During the run of the experiment, your team is assigned an office near the ISOLDE control room where data arrive in real time. Nearby, there is a kitchen to prepare meals while remaining close to the experiment. These offices are located above the laboratory, offering an incredible view of the different beamline devices (as shown in Picture 2). There must be at least 2 people present during every shift. Nevertheless, during the day, many members of the collaboration gather at the office, as a discussion can arise at any time to face challenges or review early results.

​Picture 2. Sight of ISOLDE from the meeting hall during an experimental measurement in 2024.

​Finally, in April of this year, I was invited to take part in a measurement at GANIL, located in the city of Caen in northern France. My first stay there, just a short 3-week visit, only allowed me to tour the laboratory. This time, however, I returned as a user, which was an entirely different and rewarding experience. I was so happy to meet almost all the collaborators in person and reconnect with old friends I had not seen in years. And this was possible thanks to the EUROLABS grant that supported the students' travel for this experiment.
Inside GANIL, as at CERN, there is a guesthouse where you can book a room, and a restaurant for breakfast and meals. Nearby, you can also find a mall and additional restaurants. These facilities make it easier to focus entirely on the experiment, without worrying about the daily logistics, especially for those starting the night shift at midnight. 
During this experiment, several challenges emerged, and a lot of discussions were held between the collaboration and the accelerator operators to find the best solutions. At that moment, it was inspiring to witness the resilience and ingenuity of both researchers and technicians, and I learned a lot from the solutions they employed to keep the experiment on track. It was clear that the main goal was to achieve a successful measurement. 
Apart from participating in experimental measurements, there are several other ways to visit and experience nuclear physics laboratories. One option is through a summer school, like the EURO-LABS Basic Training School, where students spend a week in the facilities, attend lectures, and gain hands-on experience with small experiments in the accelerators. I had the chance to participate in the 2023 edition of the school at IFIN-HH (Bucharest-Magurele, Romania), and it was an incredible experience. The best part is that you meet other students from different parts of the world, many of whom will eventually become your future colleagues. Another option is through an internship, as I did at the NSL at the University of Notre Dame. Laboratories also open their doors during conferences, often offering guided tours of their facilities. Depending on the scenario, there are funding opportunities that can help with travel and participation, making these experiences more accessible.
Have you already visited a Nuclear Laboratory? What are the stories about your first time in one? Are you eager to visit one in a different country? I would love to know!

Acknowledgments 
I am deeply thankful to IReNA’s blog editorial team for the space and opportunity to share my stories. I hope the readers have found them interesting and inspiring.
References

1. Institute for Structure and Nuclear Astrophysics, official webpage, https://isnap.nd.edu/ 
   
2. ISOLDE, official webpage, https://isolde.cern/  
   
3. GANIL, official webpage, https://www.ganil-spiral2.eu/