Griffiths Introduction to Elementary Particles · Problem 6.11

Quantum Electrodynamics — David J. Griffiths

Physics — QFT · abc-theory-feynman-diagrams

Problem

(a) Is

A \to B + B

a possible process in the

ABC

theory? (b) Suppose a diagram has

n_A

external

A

lines,

n_B

external

B

lines, and

n_C

external

C

lines. Develop a simple criterion for determining whether it is an allowed reaction. (c) Assuming

A

is heavy enough, what are the next most likely decay modes, after

A \to B + C

? Draw a Feynman diagram for each decay.