On 6 October the Royal Swedish Academy of Sciences awarded Halzen of the University of Wisconsin-Madison for IceCube and the discovery of high-energy neutrinos of astrophysical origin. The idea is from 1988, the instrument was finished in 2011. There is one laureate, with a 1/1 share of the 12 million Swedish kronor prize.
- The Nobel Prize in Physics 2026 goes to Francis Halzen “for decisive contributions to the IceCube Neutrino Observatory and the discovery of high-energy neutrinos of astrophysical origin”. One laureate, prize share 1/1.
- IceCube is a cubic kilometre of ice at the South Pole fitted with light sensors. The idea was presented in 1988, the instrument finished in 2011.
- The prize is 12 million Swedish kronor. Halzen was born in 1944 in Tienen, Belgium.
The idea is from 1988. The instrument was ready in 2011. The first high-energy neutrinos came soon after.
A neutrino passes through the Earth and through our bodies without us noticing. Very rarely one hits an atomic nucleus, and then there is a flash. Sensors set into something clear and still can catch the flash.
The Academy explains it this way: the South Pole ice is free from interference and the area is geologically stable, with no earthquakes. High-energy neutrinos are very rare, so you need an enormous volume of ice to observe enough collisions; IceCube covers a full cubic kilometre. Unlike other particles, a neutrino reaches us without changing direction or losing energy, and so it carries information nothing else does.
Much about the sources of high-energy neutrinos is still a mystery: what they are, where they are and what happens inside them, the Academy writes. The instrument from 2011 is still collecting data.