DECEMBER 21, 2017
Each year Science's news staff announce their selection of the top 10 scientific achievements of the year and award the title "Breakthrough of the Year" to the achievement determined to be the most significant. For 2017 the title of "Breakthrough of the Year" was awarded to Cosmic convergence, the first observation of a neutron-star merger.
In the running for Breakthrough of the Year was A tiny detector for the shiest particles, the detection of coherent neutrino scattering by the COHERENT collaboration. “The one-of-a-kind particle physics experiment at Oak Ridge National Laboratory was the first to measure coherent scattering of low-energy neutrinos off nuclei,” said ORNL physicist Jason Newby, technical coordinator of the COHERENT collaboration. The research, performed at ORNL’s Spallation Neutron Source (SNS) and published in Science, provides compelling evidence of a neutrino interaction process theorized over four decades ago.
The neutrino–nucleus interactions observed by COHERENT are not just of interest to theorists, as they also have practical application to the study of neutrino dynamics which occur during neutron star formation and supernovae explosions.
“When a massive star collapses and then explodes, the neutrinos dump vast energy into the stellar envelope,” said physicist Kate Scholberg of Duke University, COHERENT’s spokesperson. “Understanding the process feeds into understanding of how these dramatic events occur.”
Coherent elastic scattering is also relevant for detecting the enormous neutrino burst from a supernova. “When such an event occurs in the Milky Way, neutrinos of all flavors will bump into nuclei, and sensitive dark matter detectors may observe a burst of tiny recoils,” she said.
“COHERENT’s data will help with interpretation of measurements of neutrino properties by experiments worldwide,” Scholberg concluded. “We may also be able to use coherent scattering to better understand the structure of the nucleus.”