Physics Nobel for probing neutrino mystery

By showing neutrinos change identity and gain mass, Arthur McDold and Takaaki Kajita revolutionized scientists’ understanding of matter

STOCKHOLM, Oct 6: The 2015 Nobel Prize for physics has been jointly awarded to two scientists, Japan’s Takaaki Kajita and Cada’s Arthur B McDold, the Royal Academy of Sciences in Stockholm announced on Tuesday.

According to an official statement issued by the academy, Takaaki, 56, and McDold, 72, were awarded for their key contributions to the experiments which demonstrated that neutrinos change identities.

This metamorphosis requires that neutrinos have mass. The discovery has changed our understanding of the innermost workings of matter and can prove crucial to our view of the universe, the statement said.

The two physicists, conducting their experiments in two laboratories built inside disused mines lying deep underground in Japan and Cada, worked on two types of subatomic particles — solar neutrinos and atmospheric neutrinos.

Takaaki had presented the discovery that neutrinos from the atmosphere switch between two identities on their way to the Super-Kamiokande detector in Japan.

Meanwhile, the research group in Cada led by McDold could demonstrate that the neutrinos from the Sun were not disappearing on their way to Earth. Instead they were captured with a different identity when arriving to the Sudbury Neutrino Observatory in Ontario, Cada.

The discovery rewarded with this year’s Nobel Prize in Physics have yielded crucial insights into the all but hidden world of neutrinos, the statement added.

Neutrinos, the second most common subatomic particle in the entire cosmos after photons, were poorly understood by particle physicists. They are among the few fundamental particles that make up matter and have no electric charge.

It is the global quest of scientists to understand more properties of neutrinos which are created in reactions between cosmic radiation and the Earth’s atmosphere, and by nuclear reactions in the Sun. They are the inhabitants of “a hidden world,” and yet constantly bombard the Earth. (IANS)