The study was recently published in the scientific journal Nature. Comparisons between antiatoms and normal atoms can provide clues as to why we only see normal matter in the universe. The results come from an international collaboration that includes researchers at Stockholm University.  

 
Svante Jonsell
Svante Jonsell
 

Our normal matter consists of atoms and molecules, which in turn are comprised of smaller particles. For each particle there is also a mirror image, an anti-particle.

 "As far as we know, antimatter is similar to normal matter except that the electrical charge is reversed. Nevertheless, there is an obvious difference – the entire world around us is comprised only of normal matter. We don't yet know why this is. Perhaps the mirror image is not entirely perfect?" says Svante Jonsell at Stockholm University, one of the researchers involved in achieving the results. Svante Jonsell is a member of the international ALPHA research group working at CERN, The European Organization for Nuclear Research.

To look for deviations in the mirror images the ALPHA researchers have generated antiatoms and then captured them in an atom trap. The researchers then succeeded in taking the next step and were able to hold the antiatoms in place for a whole 1000 seconds. This meant it was possible to at last begin to study their properties. The researchers have now achieved their next objective, by demonstrating that the atoms react to particular types of microwaves.

"Just as the irradiation in a microwave oven is set to the correct frequency to heat water, there is a certain frequency that causes hydrogen atoms to be expelled from a magnetic atom trap," says Svante Jonsell. "What we have shown is that antihydrogen atoms are expelled at the same frequency as normal hydrogen atoms. When we set the microwaves to another frequency, or if we have no microwaves at all, the antiatoms remain in the trap. This shows that atoms and antiatoms react in the same way to microwaves," Svante Jonsell explains.

The work of making more accurate measurements is now in progress, which demands more antiatoms than the few that can currently be trapped at any one time. Other properties of antiatoms will also be studied, such as how they react to laser-generated light and if gravity causes them to fall in the same way as normal atoms do. 

-Antihydrogen can help us understand the universe, says Svante Jonsell from Stockholm University.
 

Articels

Nature: http://www.nature.com/nature/index.html
ALPHAs webste: http://alpha.web.cern.ch/alpha/
CERNs press office : http://press.web.cern.ch/press/
Svante Jonsells website:  http://www.atom.physto.se/~jonsell/