To Begin With

Our laboratory is a new group that started from April 2025.

High-energy physics is an experimental research field that aims to uncover new physics related to fundamental questions of the Universe—such as the nature of dark matter and the origin of matter in the Universe—by searching for physics beyond the Standard Model (BSM). This field is driven by a combination of high-energy collider experiments, exemplified by the CERN Large Hadron Collider (LHC) in Switzerland, which discovered the Higgs boson in 2013, and a wide variety of small- and medium-scale experiments that complement these collider programs.

In our group, we promote research on physics and detector technologies for future collider experiments, with the goal of realizing Higgs factories such as the International Linear Collider (ILC), a proposed successor to the LHC. We also lead the EBES experiment, a beam-dump search for axion-like particles (ALPs) conducted using the accelerator facilities at the High Energy Accelerator Research Organization (KEK) in Tsukuba, making full use of our detector technologies developed for collider experiments. In addition, we actively conduct research on deep learning in collaboration with other laboratories at ICEPP, the University of Tokyo, as well as domestic and international partner institutions, so that these methods can be effectively applied to our experiments.

A Higgs factory is a global project that can only be realized through close cooperation among researchers worldwide. Working together with colleagues from France, Germany, China, and other countries, we are engaged in international collaborative research toward this goal. If you are highly motivated to work with researchers around the world, contribute to the success of large-scale international projects, and explore the mysteries of the Universe, we warmly welcome you to join us. Please feel free to contact us—we would be happy to provide further details to anyone interested.

Research Topics

More details will be available soon. In the meanwhile, please refer to my personal page: Suehara's page
For ILC-related research at ICEPP, please visit the ICEPP ILC Group webpage: ICEPP ILC group page

Major Research Topics

Higgs Factory

A Higgs factory is a next-generation large-scale project: an electron–positron collider that uses a massive accelerator together with ultra-precise detectors to perform precision measurements of the Higgs boson with a sensitivity up to ten times greater than that of the current LHC experiments, thereby addressing fundamental mysteries of the Universe. Among the proposed Higgs factories, the International Linear Collider (ILC) is a collider based on a 20-km linear accelerator, and is being pursued as an international project with the goal of construction in Japan. In our laboratory, we work in collaboration with researchers worldwide on physics analyses and detector R.D, aiming for the early realization of a Higgs factory, with the start of experimental operation around 2040.
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Search for Unknown Particles

We are promoting a search for new particles—axion-like particles (ALPs)—through the EBES beam-dump experiment using a high-intensity beam. Taking advantage of the high-intensity electron/positron linear accelerator at KEK (Tsukuba), this experiment is a relatively small-scale project carried out by a team of about ten people. Nevertheless, EBES can achieve a sensitivity for ALP searches that in some regions partially surpasses that of much larger experiments involving on the order of one hundred collaborators worldwide.
Unlike large-scale experiments, in EBES you can directly control many aspects of the experiment yourself. The opportunity to search for unknown particles with your own hands is one of the most attractive features of this project.
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Our group members are also taking parts in the MEG experiment and its future program (PIONEER)and the J-PARC muon g-2/EDM experiment.

Technical Development for our Major Research Topics

Deep Learning

Deep learning technologies, exemplified by ChatGPT, have undergone remarkable advances in recent years and we are now entering an era in which they are transforming the world. In our group, we develop methods to reconstruct physical events with higher accuracy from detector data by leveraging state-of-the-art deep learning approaches, such as Transformers—the core technology behind GPT—and graph neural networks.
Next-generation detectors will incorporate far more detector elements than conventional systems, producing extremely rich information. Research on deep learning methods that can fully exploit this information has therefore become a top priority.

Calorimeter development

A calorimeter is one of the key components in particle-physics detectors—it measures the total energy of particles. For Higgs factories, however, the calorimeter design is quite different from traditional ones. Instead of using coarse detector blocks, we use a highly segmented imaging calorimeter, where the detector is finely divided in 3D. This allows us to “see” particle showers in much greater detail, which is especially important for measuring jets (collimated sprays of particles such as hadrons) with high precision. Accurate jet measurements play a crucial role in both Higgs studies and searches for new physics. In our laboratory, we are working on several advanced calorimeter technologies. These include calorimeters using silicon pad sensors, as well as highly granular calorimeters based on dual-readout techniques, which combine scintillation and Cherenkov detectors.