compute_spin_colour_correlation_rcl

compute_spin_colour_correlation_rcl(npr, p, i1, i2, v, order='LO')

Computes the spin-colour-correlated summed squared amplitude, between particle with leg number i1 and particle with leg number i2, for the process with process number npr. The spin-correlation is achieved by a user-defined polarization vector v for the particle with leg number i1, which substitutes the usual one.

Parameters:
  • npr (int) – process number
  • p (float[l][4]) – external momenta of the process with l legs
  • i1 (int) – quark/anti-quark at leg i1
  • i2 (int) – quark/anti-quark at leg i2
  • v (complex[4]) – polarization vector
  • order (str) – either ‘LO’ (default) or ‘NLO’
Returns:

(A2scc, momcheck)

Return type:

(float, bool)