# Subatomic rotations in a plane Abelian group

1. Nov 14, 2007

### genloz

1. The problem statement, all variables and given/known data
5. The Z boson has a width of 2.4952 GeV:
a. The Z decays 3.363% of the time in e+e-calculate the partial width of
$$Z \rightarrow e+e-$$.
b. The
$$J/ \psi$$ (A cc bar state) has a width of 93.4 KeV. Is its lifetime is longer or shorter than the Z lifetime? Explain.
c. Calculate the
$$J/ \psi$$ lifetimes.

2. Relevant equations
None given.

3. The attempt at a solution

(a) I think: 2.4952/100*3.363=0.084GeV is correct but I'm not sure why?

(b) I figure a bigger E means a smaller t, so it would be longer, but again I'm not sure of the physics...

(c) I have no idea how to start... does
$$J/ \psi$$ lifetimes have another more google friendly search name?

Thanks!

2. Nov 14, 2007

### genloz

Whoops, I typed in the wrong title and now can't work out how to change it...sorry!