// BBC WORLD NEWS — MONDO
'Ghost particles' from space telescope wins physics Nobel
Prof Francis Halzen won for "decisive contribution" to developing the IceCube Neutrino Observatory
Belgian-born physicist Prof Francis Halzen has won the Nobel Prize in Physics for his pioneering work on an observatory that detects particles from space, shedding light on the distant universe.
Halzen led the development of IceCube at the South Pole, which uses a cubic kilometre of Antarctic ice fitted with light sensors to detect particles called neutrinos. These carry information about violent, high-energy processes in the cosmos.
The Royal Swedish Academy of Sciences said "his vision and scientific leadership have been fundamental for the IceCube Neutrino Observatory".
He first presented his vision for detecting neutrinos at the South Pole in 1988.
Halzen, who is now a US citizen at the University of Wisconsin–Madison, told a news conference that he was surprised his idea worked so well.
"I have to emphasise how lucky I was. Because when we started this project, everybody realised this was maybe a good idea, but very few thought it would work, including myself."
Scientists in a race to discover why our Universe exists
Neutrinos are elusive subatomic particles. The Sun produces vast numbers of them: every second, billions pass harmlessly through an area the size of your fingernail.
But IceCube is searching for much higher-energy neutrinos, those produced by violent processes far beyond our Solar System — in distant galaxies.