A quark (from within a proton) and an antiquark
(from an antiproton) colliding at
high energy can annihilate to produce a top
quark and a top antiquark, which then decay into other particles.
- Frame 1: One of the proton's quarks and one of the
antiproton's antiquarks are heading toward a collision.
- Frame 2: The quark and antiquark collide and annihilate....
- Frame 3: ...into virtual gluons.
- Frame 4: A top and antitop quark emerge from the gluon cloud.
- Frame 5: These quarks begin moving apart, stretching the
color force field
(gluon field) between them.
- Frame 6: Before the top quark and
antiquark have moved very far, they decay into a bottom and antibottom
quark (respectively) with the emission of W force carrier particles.
- Frame 7: The new bottom quark and antibottom
quark rebound away from the emitted W force carrier particles.
- Frame 8: An electron and neutrino emerge from the
virtual W- boson, and an up quark
and down antiquark emerge from the
virtual W+ boson.
- Frame 9: The bottom quark and bottom antiquark,
electron, neutrino, up quark,
and down antiquark all move away from one another.
What is wrong with this picture? [ Answer ]
The intermediate stages of this
process occur in about a billionth of
a billionth of a billionth of a second, and are not observable.