Subatomic rotations in a plane Abelian group

genloz
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Homework Statement


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.

Homework Equations


None given.


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