UCL News


Particle behaviour analysed

27 September 2006

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A huge international collaboration of scientists has uncovered the strange behaviour of a particle called the B_s meson, which switches between matter and antimatter 3 trillion times a second.

The CDF collaboration at the US Department of Energy's Fermi National Accelerator Laboratory in Illinois, which involves scientists from UCL and 60 other universities from around the world, announced the discovery on Monday. The information could help scientists to understand more about how the early universe was formed.

The B_s meson does not exist in nature today, but is thought to have existed in the early universe. It can only be created using powerful particle accelerators. Scientists hope that by assembling a large number of particles such as the B_s meson and obtaining precise measurements of their behaviour, they can learn how the particles interacted to shape the universe.

These findings, which end a 20-year search for answers about the mysterious particle, could also open up new branches of physics beyond the 'standard model', which scientists believe is incomplete.

Data was acquired between February 2002 and January 2006, an operating period known as Tevatron Run 2, during which tens of trillions of proton-antiproton collisions were produced at the world's highest-energy particle accelerator. The results have been submitted in a paper to 'Physical Review Letters'.

To find out more, follow the links at the bottom of this article.

Image: Aerial view of the accelerators at the Fermilab, in Battavia, Illinois. (Fermilab)