# Top-Quark Mass, March 2014

 One of the early quantitative successes of the electroweak theory was the successful anticipation of the top-quark mass. Quantum corrections involving virtual top quarks were the dominant contributions sensitive to parameters unknown in the early 1990s. I collected the top mass favored by simultaneous fits to many electroweak observables as a function of time in Figure 1 of Chris Quigg, "Top–ology," Phys. Today 50N5, 20 (1997) [extended version at hep-ph/9704332]. Here is an updated version of that plot, together with a masked version that shows the indirect determinations before the discovery of the top quark. Click on a thumbnail to retrieve a plot. Caption: Indirect determinations of the top-quark mass from fits to electroweak observables (green circles) and 95% confidence-level lower bounds on the top-quark mass inferred from direct searches in $$\bar{p}p$$ collisions, assuming that standard decay modes dominate (broken line). Direct measurements of $$m_{t}$$ by the CDF (blue triangles) and D0 (inverted red triangles) Collaborations are shown at the time of initial evidence, discovery claim, and thereafter. The Tevatron averages from direct observations are shown as magenta squares. The first LHC averages are shown as a crossed box. The March 2014 World Average is represented as a cyan diamond.