Francis Halzen wins 2026 Nobel Prize in Physics for neutrino research

Belgian-American physicist Francis Halzen won the 2026 Nobel Prize in Physics on Tuesday for his contributions to the IceCube Neutrino Observatory and the discovery of high-energy neutrinos originating beyond the solar system.

Halzen, 82, is a professor at the University of Wisconsin–Madison, the lead institution for IceCube. He proposed in 1988 that clear glacial ice at the South Pole could be used to detect neutrinos, elusive subatomic particles that rarely interact with matter. His idea led to the construction of IceCube, an observatory completed in 2011 that uses thousands of light sensors embedded across a cubic kilometre of Antarctic ice.

When a neutrino occasionally collides with an atomic nucleus, the resulting charged particles produce a flash of light. IceCube’s sensors record the light’s pattern and timing, allowing researchers to estimate the neutrino’s direction and investigate the distant, high-energy cosmic processes that produced it.

“His tenacity and scientific vision has paved the way for a new kind of astronomy,” Nobel Committee for Physics chair Mark Pearce said. The Royal Swedish Academy of Sciences said Halzen’s vision and scientific leadership were fundamental to the observatory.

Halzen, who spoke with the committee by phone from Italy, said the award was a surprise and emphasized that few researchers initially believed the project would work. He will receive 12 million Swedish kronor, approximately $1.2 million.