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)