Twist2GluonOperator[{p, mu, a}, {nu, b}]
or
Twist2GluonOperator[p, {mu, a}, {nu, b}]
or
Twist2GluonOperator[p, mu,a, nu,b]
yields the 2-gluon
operator (p
is ingoing momentum corresponding to Lorentz
index mu
).
Twist2GluonOperator[{p,mu,a}, {q,nu,b}, {k,la,c}]
or
Twist2GluonOperator[ p,mu,a , q,nu,b , k,la,c]
gives the
3-gluon operator.
Twist2GluonOperator[{p,mu,a}, {q,nu,b}, {k,la,c}, {s,si,d}]
or Twist2GluonOperator[p,mu,a , q,nu,b , k,la,c , s,si,d]
yields the 4-Gluon operator.
The dimension is determined by the option Dimension
. The
setting of the option Polarization
(unpolarized:
0
; polarized: 1
) determines whether the
unpolarized or polarized Feynman rule is returned.
With the setting Explicit
set to False
the
color-structure and the (1+(-1)^OPEm
) (for polarized:
(1-(-1)^OPEm)
) is extracted and the color indices are
omitted in the arguments of Twist2GluonOperator
.
Overview, Twist2QuarkOperator.
The setting All for Explicit performs the sums.
[{p, \[Mu], a}, {q, \[Nu], b}, {r, \[Rho], c}, Polarization -> 1, Explicit -> All] Twist2GluonOperator
\left(1-(-1)^m\right) g_s f^{abc} \left(O_{\nu \, \rho \, \mu }^{\text{G3}}(q,r,p)\right)