Asymmetric di-jet production in polarized hadronic collisions

Using the collinear QCD factorization approach, we study the single-transverse-spin dependent cross section Δσ(S⊥) for the hadronic production of two jets of momenta P1=P+q/2 and P2=−P+q/2. We consider the kinematic region where the transverse components of the momentum vectors satisfy P⊥≫q⊥≫ΛQCD. For the case of initial-state gluon radiation, we show that at the leading power in q⊥/P⊥ and at the lowest non-trivial perturbative order, the dependence of Δσ(S⊥) on q⊥ decouples from that on P⊥, so that the cross section can be factorized into a hard part that is a function only of the single scale P⊥, and into perturbatively generated transverse-momentum dependent (TMD) parton distributions with transverse momenta k⊥=O(q⊥).