Hi,
DoPolarizationSums and FermionSpinSum do not implement polarized
calculations. But this is not really an issue, since one can do it by hand
with some extra code.
For what concerns the spinors, I would do something along the lines of
Chapter 7.10 in Bjorken, i.e. put the spin projection operator by hand
in the right places and then use FermionSpinSum as usual.
If you have left- and right-handed particles, it is even simpler, since your
polarization operator is just GA[6] or GA[7], as in
https://feyncalc.github.io/FeynCalcExamplesMD/QED/Tree/ElAel-MuAmu
In the case of vector particles, I would try to express the polarization
vectors
in terms of the kinematic invariants already present in the calculation,
e.g. as
in Section 5.3 of arXiv:0709.1075.
Cheers,
Vladyslav
Am 24.04.20 um 19:03 schrieb Timur:
> Dear FeynCalc author. I am trying to calculate single and double compton scattering cross section for specified polarization of ingoing and outgoing photons. I know how to perform summation over polzariations with the use of DoPolarizationSums and FermionSpinSum commands. But how I can calculate squared amplitude for specified fermion spin and photon polarizations?
>
This archive was generated by hypermail 2b29 : 09/04/20-12:55:05 AM Z CEST