Griffiths Introduction to Elementary Particles · Problem 9.14
Weak Interactions — David J. Griffiths
Physics — QFT · gluon-gluon-scattering
Problem
(Gluon-gluon scattering)
(a) Draw the lowest-order diagrams (there are four of them) representing the interaction of two gluons.
(b) Write down the corresponding amplitudes.
(c) Put the incoming gluons into the color singlet state; do the same for the outgoing gluons. Compute the resulting amplitudes.
(d) Go to the CM frame, in which each gluon has energy E; express all the kinematic factors in terms of E and the scattering angle θ. Add the amplitudes to get the total, M.
(e) Find the differential scattering cross section.
(f) Determine whether the force is attractive or repulsive (if it is the former, this may be a likely glueball configuration).