Peking University, Beijing. 25th Feb, 2009: Recently, Professor Li Chongsheng of the Dept. of Physics, Peking University published an article “Next-to-leading order QCD corrections to the top quark decay via model-independent FCNC couplings” in Phys. Rev. Lett. (the United States), making research on the loop effect of QCD via model-independent FCNC couplings and its influence upon the decay branching ratio.

It’s said that, thanks to this article and other relevant articles Prof. Li previously published in Phys. Rev. D, the CDF team of Fermi National Laboratory of America was able to find out the upper limit in the experiment of top quark QCD anomalous coupling and the correspondent upper limit in the experiment of the decay branching ratio, which has been made public in ICHEP in 2008 and special thanks were given to Prof. Li.

Since 14 years ago when the top quark was discovered for the first time in Tevatron accelerator at Fermi National Laboratory, it has been one of the hottest topics in particle physics. What does the top quark weigh much more heavier than other basic particles discovered? What kind of clues will it provide to the most-concerned issues in physics such as the origin of the weight, the symmetry breaking and the new physics beyond the standard model and so on? Now, the Tevatron accelerator at Fermi National Lab is able to “produce” thousands of top quarks every year. From the later half of this year, the Large Hadron Collider (LHC) at European Organization for Nuclear Research will produce millions of top quarks every year. It’s hoped that with such a large number of top quarks produced, the answers to these questions will be solved.

Prof. Li and his team have conducted a systematic research for a long time on the questions raised above and made special contribution to the model-independent production and decay of top quark.

Edited By : Cai Ying
Translated By : Lin Jingxian
Source : Beida news (Chinese)