Our Earth may have clues to study universe through neutrinos
Scientists have found the neutrinos that are far beyond the known energy of neutrinos expected to be produced in the Earth’s atmosphere.
Neutrinos are the elementary particles that are thought to be produced outside of our solar system. High-energy neutrinos have the ability to pass through normal matter and billions of them pass through Earth every second.
The IceCube neutrino observatory at the South Pole previously detected 28 high-energy neutrinos. Two of the discovered neutrinos — nicknamed Bert and Ernie – were of special interest due to their extremely high-energy of over 1,000,000,000,000,000 electron volts or 1 peta-electron volt (PeV).
In the new analysis, scientists have discovered 26 additional events beyond 30 teraelectronvolts that is more than the energy expected for neutrinos produced in the atmosphere of the Earth.
“While it is premature to speculate about the precise origin of these neutrinos, their energies are too high to be produced by cosmic rays interacting in the Earth’s atmosphere,” said Penn State Associate Professor of Physics Tyce DeYoung, deputy spokesman of the IceCube Collaboration, “strongly suggesting that they are produced by distant accelerators of subatomic particles elsewhere in our galaxy or even farther away.”
This finding has opened new era of astronomy by which we can observe the universe using high-energy neutrinos as these neutrinos are thought to be produced from distant cosmic accelerators and can help in study of highest-energy and most-distant phenomena in the Universe.
“Scientists have been searching high and low for these super-energetic neutrinos using detectors buried under mountains, submerged in deep lakes and ocean trenches, lofted into the stratosphere by special balloons, and in the deep clear Antarctic ice at the South Pole,” said Doug Cowen, also from Penn State, who has worked on IceCube for over a decade. “To have finally seen them after all these years is immensely gratifying.”
Coolest new astronomy tool tracks high-energy neutrinos on ice – Penn State News (http://news.psu.edu/story/296151/2013/11/21/research/coolest-new-astronomy-tool-tracks-high-energy-neutrinos-ice)
IceCube Collaboration (2013). Evidence for High-Energy Extraterrestrial Neutrinos at the IceCube Detector Science DOI: 10.1126/science.1242856