On 14 October, the inaugural Werner Hofmann Scientific Award was presented at the CTAO Construction Meeting that is taking place this week at the CTAO Science Data Management Centre (SDMC) in Zeuthen, Germany. Following a rigorous nomination and review process by an international panel of experts, the award was given to Shotaro Abe, a researcher at the Institute for Cosmic Ray Research (ICRR) and University of Tokyo, for his groundbreaking work on dark matter and PeVatrons. Abe received the award from Prof. Werner Hofmann, which included a trophy, a monetary prize, and the opportunity to present his research to an audience of CTAO experts from around the world.
Abe’s doctoral studies, completed this past March, focused on two major mysteries in astrophysics: dark matter, the invisible form of matter that makes up around 25% of the Universe but whose nature remains unknown, and PeVatrons, cosmic accelerators capable of producing particles at petaelectronvolt (PeV) energies, far beyond the reach of human-made accelerators.
To tackle these challenges, Abe developed innovative large-zenith-angle observation techniques, which involve observing sources low on the horizon. These were long considered impractical because the atmosphere absorbs more gamma rays at such angles, and the telescope’s response strongly varies, creating complex uncertainties. As a member of the CTAO LST Collaboration, Abe led an international team working with the Large-Sized Telescope (LST) prototype, LST-1, located on CTAO-North, and through careful calibration and analysis, he was able to turn these challenges into an advantage, extending LST-1’s sensitivity above 20 TeV with just 40 hours of observation.
Alongside these technical achievements, Abe published influential scientific studies. For dark matter, he investigated the Galactic Centre to search for gamma rays from the annihilation of Higgsino, a dark matter candidate. Using telescope simulations, he showed that CTAO-North could detect this elusive particle by 2030, demonstrating that such searches are feasible from the northern hemisphere and not only from the south, as previously thought. In his PeVatron studies, Abe applied wide-field analyses methods, which examine a large region of the sky simultaneously, revealing subtle variations in the gamma-ray spectrum across the Galactic Centre and providing new insights into the origin and structure of extreme cosmic accelerators.
Launched in early 2025 by the CTAO Central Organisation, the Werner Hofmann Scientific Award recognises early-career researchers who make significant contributions to gamma-ray astronomy and the CTAO through innovative research, technical advances, or emerging scientific leadership. Named after Prof. Hofmann, a pioneering figure in the field, the award honours his lasting impact on the vision and design of the CTAO. The evaluation committee for the 2025 edition brought together experts from different countries and fields, including Hofmann, to select the winner: Catherine Boisson (Observatoire de Paris, France), Rubén López-Coto (Instituto de Astrofísica de Andalucía, IAA-CSIC, Spain), Alison Mitchell (Friedrich-Alexander-Universität Erlangen-Nürnberg, Germany), Masahiro Teshima (Max Planck Institut für Physik, MPI, and ICRR, Japan), and Roberta Zanin (CTAO Project Scientist).
Congratulations to Shotaro Abe on this well-deserved recognition!