Neutrino emissions behind Suns energy generation observed in lab

A team of US and European researchers have observed the tell-tale signals of neutrinos emitted by thermonuclear fusion reactions that power the Sun deep in its interior.

Washington, Aug 28 : A team of US and European researchers have observed the tell-tale signals of neutrinos emitted by thermonuclear fusion reactions that power the Sun deep in its interior.

At approximately 15 million degrees, protons - the nuclei of hydrogen atoms - and light elements fuse to form new nuclei. Several such steps eventually convert the hydrogen in the Sun into helium, releasing about 25 million times more energy per gram than TNT, oil, or coal.

"While the neutrinos, which are uncharged elementary particles, only take about eight minutes to reach the earth, the thermal energy produced at the centre of the Sun only appears as sunlight some 50 thousand years later, after diffusing to the Sun's surface," said Bruce Vogelaar professor of physics and leader of Virginia Tech's research team for the project.

"The only way to prove the validity of this model of solar energy generation is to observe these neutrinos which easily travel right through the sun because of their weak interaction with matter. Of special interest are those neutrinos from the decay of 7Be, a critical step in the energy chain of the Sun," said Prof. Vogelaar.

Prof. Vogelaar and his team observed these neutrinos directly for the first time in the Borexino detector, located under the Gran Sasso peak in the Apennine mountain range about 100 miles east of Rome.

The Borexino is a massive detector that contains some 350,000 gallons of organic liquid. Its central region detects neutrinos by seeing the light given off when a neutrino collides with an electron, using some 2,200 photosensors arrayed around the detector.

"The Sun emits copious amounts of neutrinos in a wide range of energies. About 10 billion pass through your thumbnail each second," said Prof. Vogelaar.

"The scientific and technological achievement of Borexino is a testament to the value of international collaboration and the ingenuity and tenacity of the Borexino collaboration over 20 years to achieve the present success," he said.

"We expect that information on the 7Be solar neutrinos will clarify the sun's energy cycle in great detail and throw light on the nature of the neutrino itself," he added.

ANI