Francis Halzen wins 2026 Physics Nobel for discovery of cosmic high-energy neutrinos

The 2026 Nobel Prize in Physics has been awarded to Francis Halzen “for decisive contributions to the IceCube Neutrino Observatory and the discovery of high-energy neutrinos of astrophysical origin”, the Royal Swedish Academy of Sciences said.

Halzen, a professor at the University of Wisconsin–Madison, laid the foundation for the IceCube Neutrino Observatory, which uses glacial ice at the South Pole to detect neutrinos originating from the distant cosmos.

Neutrinos are extremely elusive particles that rarely interact with matter. Because high-energy cosmic neutrinos are also very rare, IceCube uses an enormous volume of ice to capture enough interactions for researchers to study them.

The observatory covers about one cubic kilometre of Antarctic ice and was completed in 2011. Researchers soon detected the first high-energy neutrinos and, a few years later, published the discovery of neutrinos that could be traced to sources far beyond the Solar System.

The discovery opened the search for the sources of these high-energy particles and established a new way of studying the universe.

The neutrino interactions continuously recorded by IceCube can provide information about the violent environments in which high-energy neutrinos are produced and could help reveal previously unknown cosmic phenomena.

Halzen, who was born in Tienen, Belgium, in 1944, said it was a “great pleasure” to hear about the prize when the Nobel committee contacted him after the announcement.

The 2026 Physics Nobel is part of Nobel announcement week. The Chemistry Nobel will be announced on 7 October, followed by the Literature Nobel on 8 October and the Peace Nobel on 9 October. The Sveriges Riksbank Prize in Economic Sciences will be announced on 12 October.

The laureate will receive 12 million Swedish kronor, about $1.2 million. The award will be presented on 10 December, Nobel Prize Day and the death anniversary of Swedish inventor Alfred Nobel.