UA1

After the discovery of the W and Z boson, the UA1 collaboration went on to search for the top quark. Physicists had anticipated its existence since 1977, when its partner — the bottom quark — was discovered. It was felt that the discovery of the top quark was imminent. In June 1984, Carlo Rubbia at the UA1 experiment expressed to the New York Times that evidence of the top quark "looks really good". Over the next months it became clear that UA1 had overlooked a significant source of background. The top quark was ultimately discovered in 1994–1995 by physicists at Fermilab with a mass near 175 GeV.