- Number 297 |
- October 12, 2009
CDF achieves most precise measurement of the top quark mass
The cross marks the spot as the
likely value of the top quark mass,
based on the evaluation of 630 top
The CDF collaboration at DOE’s Fermi National Accelerator Laboratory has achieved the world’s most precise measurement of the mass of the top quark, the heaviest elementary particle ever observed. Using the Collider Detector at Fermilab, a 6,000-ton instrument that records particles emerging from proton-antiproton collisions, scientists determined the top quark mass to be 172.64 GeV/c2, almost as heavy as a gold atom. Yet the top quark would fit easily inside a single proton and has no substructure. The uncertainty of CDF’s mass measurement is less than one percent (+/- 1.58 GeV/c2). For the analysis, CDF scientists sifted through collision data recorded in the last eight years with the Tevatron collider at Fermilab, identified 630 top quark pairs and used them to determine the mass.
[Kurt Riesselmann, 630.840.5681,