. . "The Upsilon meson (\u03D2) is a quarkonium state (i.e. flavourless meson) formed from a bottom quark and its antiparticle. It was discovered by the E288 collaboration, headed by Leon Lederman, at Fermilab in 1977, and was the first particle containing a bottom quark to be discovered because it is the lightest that can be produced without additional massive particles. It has a lifetime of 6980120999999999999\u26601.21\u00D710\u221220 s and a mass about 7000946000000000000\u26609.46 GeV/c2 in the ground state."@en .