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unscientific
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Homework Statement
(a) Explain the results.
(b) Why is the cross section much higher? Suggest the dominant decay product pair.[/B]
Homework Equations
The Attempt at a Solution
[/B]
Part(a)
For a centre of mass energy of ##170GeV##, you produce pairs of oppositely charged ##W^{\pm},W^{\mp}## bosons. It is kinematically forbidden to produce ##Z,Z## pair and forbidden by charge to produce ##Z,W^{\pm}## pairs.
First group of 4 hadronic jets can be explained by production of 2 pairs of quark/anti-quark stream. Number of combinations = 3x4 = 12 because of 3 colours possible. ~45%
Second group can be explained by a quark/anti-quark stream and a lepton/neutrino stream. Number of possibilities = 3x2 + 2x3 = 12. (3 types of leptons, 2 charge types) ~45%
Third group can be explained by 2 pairs of lepton/neutrino stream. Number of possibilities = 3 (leptons must be oppositely charged) ~10%
Part (b)
This question stumbled me. Is there something special happening at 125 GeV? I suppose the heaviest quark-anti-quark pair it can decay to is the bottom/anti-bottom quark? Why is the cross section so much higher? Why is it that in part (a) only {u,d,c,s} quarks/anti-quarks are produced and not bottom (b) quarks??