Beamline for Schools (BL4S) is a physics competition that was initiated by CERN, the European Laboratory for Particle Physics, and is open to secondary school pupils from all around the world. Participants are invited to submit a proposal for a physics experiment to be undertaken at the beamline of a particle accelerator, either at CERN or at one of the partner institutes: Deutsches Elektronen-Synchrotron (DESY) in Hamburg, Germany, and Elektronen-Stretcher-Anlage (ELSA) of the University of Bonn, Germany. In 2025, a record number of five winning teams have been chosen, based on both the scientific merit of their proposals and the communication merit of their submission videos.
The Spallateam, a team from the Collège Cardinal Mercier in Belgium, and the team Physical, from Cağaloğlu Anadolu Lisesi in Turkey, will travel to CERN in September 2025 to perform their proposed experiments. The teams Dawson Technicolor from Dawson College in Canada and Pumas in Kollision from Escuela Nacional Preparatoria N° 6 Antonio Caso in Mexico will carry out their experiments at a DESY beamline, while Team XTReme from Centennial High School in the United States will be welcomed at the University of Bonn. It is the first time that teams from Belgium and Turkey have won the competition.
A beamline is a facility that provides high-energy fluxes of subatomic particles that can be used to conduct experiments in different fields, including fundamental physics, material science and medicine.
The participation rate has been rising consistently since the launch of Beamline for Schools in 2014, with a record number of 508 teams from 72 countries submitting an experiment proposal in 2025. More than 3,500 high-school students participated this year.
“Year after year, we keep being amazed by the quality of the students’ proposals,” said Charlotte Warakaulle, CERN director for international relations. “Education is at the core of our mission, and the consistent growth in the number of students taking part in the competition demonstrates the strong interest of students in science, technology, engineering and math. We want to nurture this interest and talent, and we are looking forward to welcoming the winners on site.”
The collaboration between CERN and DESY started in 2019 during a long shutdown period of the CERN accelerators. This is the sixth year that the German laboratory has hosted competition winners.
Beate Heinemann, chair of DESY’s board of directors, adds: “My heartfelt congratulations not only to this year’s winners, but also to all the other participants. You got together and worked as teams for your proposals. Such teamwork is the first step toward great science. I look forward to welcoming the Canadian and Mexican teams at DESY and hope they will find answers to their scientific questions using the DESY beamlines.”
For the first time this year, the University of Bonn will also be welcoming a team, who will use its electron accelerator ELSA.
“At the University of Bonn we are proud to contribute the ELSA beam for the first time and very much look forward to hosting a winning team. I am very impressed by the proposal of Team XTReme, and we will do our best to provide them with a good experimental environment. We know that the BL4S participants of today are the scientists of tomorrow,” said Professor Klaus Desch, who is in charge of the ELSA accelerator facility.
“Our team proposes to compare the numbers of neutrons emitted by two different spallation targets. The first, a homogeneous target, would be made of a heavy metal: tungsten. The second target would be composite: tungsten combined with elements of aluminium, a light metal. We are hoping for an increase in neutrons in the second case,” said the Spallateam from Belgium. “We cannot wait to conduct our experiment at CERN.”
The Turkish team’s experiment focuses on optimizing nuclear spallation by investigating how different target materials and their thicknesses affect neutron yield. “This research could inform future methods for radioactive waste reduction and sustainable neutron source design,” said ,” Defne Karaoğluol from the Turkish Physical team. “Being selected to conduct our experiment at CERN feels surreal; it was beyond our dreams. Getting to be at the heart of scientific discovery, not as observers but as contributors, is the most meaningful moment of our lives so far.”
“Our experiment aims to observe the trajectories of muons with a three-dimensional scintillator-based detector, the Scintillating Chamber,” said Danah Dézémé from the Canadian Dawson Technicolor team. “The opportunity that has been presented to us fills us with so much excitement and anticipation for the future of the Scintillating Chamber, as well as for the future of particle physics as a whole.”
“Our project explores the use of kidneywood pigment and fluorite as scintillating media, combining scientific inquiry with cultural heritage,” explained Pumas in Kollision, the team from Mexico. “We aim to demonstrate that it is possible to propose new alternatives to standard procedures, thereby making them more accessible and adaptable for laboratories with limited infrastructure. Winning meant to all of us that the effort we invested was completely worth it, and we're very excited to be able to work with world-class scientists.”
“Our project investigates the production of transition radiation as high-energy electrons pass through multilayer dielectric interfaces,” said Team XTReme from the United States. “It's almost surreal to think that we've made it to the point where we get to push the boundaries of particle physics through hands-on experimentation at ELSA. We're grateful to the whole BL4S organization for making this happen, and we're so excited for this opportunity.”
The winning proposals were selected by a committee of CERN, DESY and ELSA scientists from a shortlist of 50 particularly promising experiments. In addition, three teams will be recognized for the most creative video proposals and another 15 teams for the quality of their physics outreach activities in their local communities, taking advantage of the knowledge they have gained by participating in BL4S.
Beamline for Schools is an education and outreach project funded by the CERN and Society Foundation’s donors. This 12th edition is supported notably by Rolex through its Perpetual Planet Initiative and by the Wilhelm and Else Heraeus Foundation.
