Indian origin scientist plays key role in single top quark discovery

Washington, March 10 (ANI): A scientist of Indian origin has played a key role in discovering particle collisions that produce a single top quark, one of the fundamental constituents of matter.

The scientist in question is Meenakshi Narain, professor of physics at Brown University, who has been involved with the CDF and DZero collaborations at the Department of Energy's Fermi National Accelerator Laboratory.

In 1995, Narain was a member of the DZero group at Fermi that discovered the top quark and the anti-top quark. She called the finding of a single top quark "kind of a dream come true".

"For me, this is like a 14-year journey that has come to a close," said Narain, who provided the analysis that helped scientists separate the single top quark from observational clutter.

"We have discovered the top quark in pairs. Now we can see it produced singly in a rare mode by the weak force, which means we can understand its properties better," she added.

The scientists found the single top quark through proton-antiproton collisions at Fermi, which operates the Tevatron, currently the world's highest-energy particle collider.

Previously, top quarks had only been observed when produced by the strong nuclear force. That interaction leads to the production of pairs of top quarks.

The latest discovery involves the weak nuclear force and is harder to identify experimentally.

The discovery of the single top confirms important parameters of particle physics, including the total number of quarks, and has significance for the ongoing search for the Higgs particle at Fermilab and at the Large Hadron Collider, the world's largest superparticle collider in Switzerland that is expected to begin operations anew this fall after suffering a malfunction last year.

Only one in every 20-billion proton-antiproton collisions produces a single top quark.

Even worse, the signal of these rare occurrences is easily mimicked by other background processes that occur at much higher rates.

"I am thrilled that CDF and DZero achieved this goal," said Fermilab Director Pier Oddone.

"The two collaborations have been searching for this rare process for the last 15 years, starting before the discovery of the top quark in 1995. Investigating these subatomic processes in more detail may open a window onto physics phenomena beyond the Standard Model," he added. (ANI)