Getting to Higgs

Finding Evidence for W: Some Z Decays

Remember, Z is so short-lived that we have to study its particle decay products. Zs are produced by colliding protons and antiprotons.

Zs can decay in several ways including:

Z e⁺ + e^- or
Z m⁺ + m^-

1. If the Z is produced at rest, the pairs of particles will be back-to-back (their tracks form a line that is slightly curved but looks straight to our eye).

2. Often collision events contain jets in addition to the Z. Jets are cluster of particles that originated from a quark or a gluon. Because of the momentum of the jets, the Z is often moving instead of at rest.

Z e⁺ + e^- or
Z m⁺ + m^-

Because the Z is moving, the muons or electrons will not necessarily be back-to-back. But if the Z is moving slowly, the leptons will have a large angle between them. Why?

References

Assignments: Correcting W Mass