Parametrization of the Transverse Momentum Dependent Light-Front Correlator for Gluons

We study the transverse momentum dependent light-front correlator for gluons. At the operator level this is expressed as a matrix element containing nonlocal field strength operators and gauge links bridging the nonlocality. We parametrize the leading (twist-2) gluon–gluon correlator in terms of transverse momentum dependent distribution functions for unpolarized, vector and tensor polarized targets (the latter being relevant for spin-1 targets). For a tensor polarized target there are eleven functions among which two are time reversal odd. We discuss bounds on some functions which might become useful for future applications. (author)