Resummed azimuthal decorrelation and transverse momentum imbalance of dijets at the LHC
Rong-Jun Fu, Rudi Rahn, Ding Yu Shao, Wouter J. Waalewijn, Bin Wu
A
bstract
We present a theoretical study of the azimuthal decorrelation
δϕ
and transverse momentum imbalance
q
T
in dijet production at the LHC, offering intriguing insights into the dynamics of quantum chromodynamics. We define the jet axes using the recoil-free winner-take-all (WTA) recombination scheme. For the azimuthal decorrelation
δϕ
, this axis choice eliminates non-global logarithms (NGLs) entirely. For the transverse momentum imbalance
q
T
, NGLs emerge specifically in the small jet radius limit (
R
≪ 1). In this regime, the WTA scheme simplifies the theoretical framework by restricting jet radius logarithms to the soft sector. We derive factorization formulae for both observables within soft-collinear effective theory. To address the small-
R
NGLs in the
q
T
distribution, we refactorize the soft function into global soft, collinear-soft, and ultra-collinear-soft modes. We perform the resummation of global large logarithms ln(
δϕ
) and ln(
q
T
/
Q
) up to next-to-next-to-leading logarithmic accuracy. For the
q
T
distribution, this is combined with a leading-logarithmic resummation of the non-global ln
R
terms. We match our predictions to leading fixed-order