They have had to sort through 100 billion subatomic particles to perfect their craft, but physicists using the IceCube Observatory in Antarctica now believe they are on course to create a new science: neutrino astronomy.
Neutrinos emanate from many sources, including black holes and energetic galactic cores and are known to come in three interchangeable forms, or flavours — a discovery that has won Takaaki Kajita and Arthur McDonald the 2015 Nobel prize for Physics. By learning how to channel neutrinos inside their instruments, physicists can look at distant, explosive events in a new way.
IceCube is made out of thousands of optical sensors buried deep below the surface at the south pole. They point downwards, towards the northern hemisphere, using the Earth to filter out other particles created by cosmic rays. This year, the observatory run by a consortium based at the University of Wisconsin-Madison, announced it had detected neutrinos that have come from outside our galaxy. If they can differentiate the sources of neutrinos, scientists say they will be able to link their arrival on Earth with specific astronomical events such as gamma-ray bursts or neutron star collisions and so gain new insights.
“Our next step is to develop ways to detect neutrinos very quickly and spot their source, preferably in minutes,” said Professor Albrecht Karle, an IceCube scientist. “Then we can let other astronomers know neutrinos from a particular region of space have reached Earth. They can then turn their telescopes and satellite observatories to pinpoint those sources. Neutrinos will therefore give us tip-offs about cosmic events and help us understand the physics that is going on inside them.”
