This preview shows pages 1–2. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
Unformatted text preview: Homework Set No. 5, Physics 880.02 Deadline – Friday, March 13, 2009 1. (15 pts) In the SU (2) L ⊗ U (1) Y Electroweak theory the Lagrangian for the gauge fields is L gauge = 1 4 f μν f μν 1 4 ~ F μν · ~ F μν . It involves an Abelian gauge field B μ with the field strength tensor f μν = ∂ μ B ν ∂ ν B μ and a nonAbelian field ~ W μ = ( W 1 μ , W 2 μ , W 3 μ ) with the field strength tensor F a μν = ∂ μ W a ν ∂ ν W a μ + g abc W b μ W c ν . Rewrite the Lagrangian L gauge in terms of the W ± , Z , and photon fields W μ = 1 √ 2 ( W 1 μ i W 2 μ ) W † μ = 1 √ 2 ( W 1 μ + i W 2 μ ) Z μ = B μ sin θ W + W 3 μ cos θ W A μ = B μ cos θ W + W 3 μ sin θ W . Simplify L gauge and separate the kinetic terms of the fields W μ , Z μ , A μ from the interaction terms. List all the possible interaction vertices for W ± , Z , and the photon. (You do not have to spell out the Feynman rules for the vertices.) 2. A dedicated effort is underway by experimentalists at the B factories (BABAR collab...
View
Full
Document
This note was uploaded on 07/28/2011 for the course PHYSICS 880.02 taught by Professor Kovchegov during the Winter '09 term at Ohio State.
 Winter '09
 Kovchegov
 Physics, Work

Click to edit the document details