Precision boson-jet azimuthal decorrelation at hadron colliders

The azimuthal angular decorrelation of a vector boson and jet is sensitive toQCD radiation, and can be used to probe the quark-gluon plasma in heavy-ioncollisions. By using a recoil-free jet definition, the sensitivity tocontamination from soft radiation on the measurement is reduced, and thecomplication of non-global logarithms is eliminated from our theoreticalcalculation. Specifically we will consider the $p_T^n$ recombination scheme, aswell as the $n\to \infty$ limit, known as the winner-take-all scheme. These jetdefinitions also significantly simplify the calculation for a track-basedmeasurement, which is preferred due to its superior angular resolution. Wepresent a detailed discussion of the factorization in Soft-Collinear EffectiveTheory, revealing why the transverse momentum $\vec q_T$ is more complicatedthan the azimuthal angle. We show that potential glauber contributions do notspoil our factorization formalism, at least up to and including order$\alpha_s^3$. The resummation is carried out using the renormalization group,and all necessary ingredients are collected or calculated. We conclude with adetailed phenomenological study, finding an enhanced matching correction forhigh jet $p_T$ due to the electroweak collinear enhancement of a boson emissionoff di-jets. We also compare with the Pythia event generator, finding that ourobservable is very robust to hadronization and the underlying event.