LHC and Tevatron scientists announce first joint result

Scientists working on experiments at CERN’s Large Hadron Collider (LHC) and Fermilab’s Tevatron colliders have joined forces to produce a more precise measurement of the mass of the top quark.

Scientists from the four experiments involved—ATLAS, CDF, CMS and DZero—announced their joint findings at the Rencontres de Moriond international physics conference in Italy. 

The four experiments pooled their data analysis power to arrive at a new world’s best value for the mass of the top quark of 173.34 plus/minus 0.76 GeV/c2.

Experiments at the LHC at the CERN laboratory in Geneva, Switzerland and the Tevatron collider at Fermilab near Chicago in Illinois, USA are the only ones that have ever seen top quarks—the heaviest elementary particles ever observed.  The top quark’s huge mass (more than 100 times that of the proton) makes it one of the most important tools in the physicists’ quest to understand the nature of the universe. 

The new precise value of the top-quark mass will allow scientists to test further the mathematical framework that describes the quantum connections between the top quark, the Higgs particle and the carrier of the electroweak force, the W boson. Theorists will explore how the new, more precise value will change predictions regarding the stability of the Higgs field and its effects on the evolution of the universe. It will also allow scientists to look for inconsistencies in the Standard Model of particle physics – searching for hints of new physics that will lead to a better understanding of the nature of the universe.

For more information read the press release

This graphic shows the four individual top quark mass measurements published by the ATLAS, CDF, CMS and DZero collaborations, together with the most precise measurement obtained in a joint analysis