 | Boson+jet production in hadron collisions. Here $p_V$ and $p_J$ are the momenta of the color singlet boson and the jet, and $R$ is the jet radius. By definition $\vec{q}_T=\vec{p}^J_{T}+\vec{p}^{\,V}_{T}$. The modes relevant for the observable $q_T$ include the soft modes with momentum $p_s$, and the collinear modes along the two beam directions ($n_1$ and $n_2$) and the jet direction ($n_J$). Small-angle soft modes are taken as an independent degree of freedom from those emitted from the jet at wide angle, and its momentum is denoted as $p_t$. The $n_1$-collinear and $n_2$-collinear modes and soft modes all have a transverse momentum $\sim q_T$, while the $n_J$-collinear modes carry most of the jet momentum. |