Physicists charged over strange quarks (ABC Science Online)
A snapshot within a proton showing a strange quark (red) and its antistrange partner (yellow) together with two up quarks (blue) and a down quark (green) (Image: Derek Leinweber)
Physicists charged over strange quarks
By Stephen Pincock, ABC Science Online
September 6, 2006
Scientists say they've solved a decade-old puzzle about the enigmatic 'strange quark', one of the fundamental building blocks of matter.
Their findings, published recently in the journal Physical Review Letters, help put our understanding of the universe on a more solid footing.
Associate Professor Derek Leinweber from the University of Adelaide and colleagues used a combination of supercomputing and physics to study the oddly named particle.
Strange quarks are one of six different 'flavours' of quark that combine to form protons and neutrons, two of the main components of atoms.
The others are known as 'up', 'down', 'charm', 'top' and 'bottom' quarks.
The short-lived strange quark is the most mysterious of them all, Leinweber says.
It "boils up" inside the positively charged proton and then "simmers back out of existence", he says.
Scientists have long pondered exactly how the strange quark contributes to the distribution of charge in the proton, Leinweber says.
"People have been playing around with these problems for 10 years or more."
By combining results from real-life experiments with simulations, the Adelaide team, with collaborators at the University of Edinburgh and the Thomas Jefferson National Accelerator Facility in the US, says it has calculated the strange contribution with unprecedented accuracy.
Those calculations predict that the short-lived strange quarks display an unanticipated level of symmetry in their journey.
"It's a bit of a surprise," Leinweber says. "There was some idea that the strange quark would be distributed asymmetrically."
Effective Field Theory
The research brought together expertise in supercomputing with techniques in a branch of physics called Effective Field Theory, Leinweber says.
"These are two separate areas which have been used together in a way that no-one else has thought of."
For the physics world, the findings could have major implications, particularly as experimental results coming from labs around the world are already beginning to confirm the theories of the Australian researchers.
Now, scientists are considering how to incorporate the results into research at enormous particle accelerator facilities like the Large Hadron Collider buried underground at CERN in Switzerland.
"Our result presents a huge challenge to experimental physicists in planning the next generation of experiments," says Leinweber. "Billions of dollars are going to be spent based on this result."
Ultimately, the research is helping scientists understand the universe in greater detail than ever before, Leinweber says. "It's putting our current understanding of our world on a solid foundation."