학술논문

Measurement of dijet azimuthal decorrelation in pp collisions at s=8TeV
Document Type
article
Source
European Physical Journal C. 76(10)
Subject
Nuclear and Plasma Physics
Particle and High Energy Physics
Physical Sciences
hep-ex
Atomic
Molecular
Nuclear
Particle and Plasma Physics
Quantum Physics
Nuclear & Particles Physics
Astronomical sciences
Atomic
molecular and optical physics
Particle and high energy physics
Language
Abstract
A measurement of the decorrelation of azimuthal angles between the two jets with the largest transverse momenta is presented for seven regions of leading jet transverse momentum up to 2.2[Formula: see text]. The analysis is based on the proton-proton collision data collected with the CMS experiment at a centre-of-mass energy of 8[Formula: see text] corresponding to an integrated luminosity of 19.7[Formula: see text]. The dijet azimuthal decorrelation is caused by the radiation of additional jets and probes the dynamics of multijet production. The results are compared to fixed-order predictions of perturbative quantum chromodynamics (QCD), and to simulations using Monte Carlo event generators that include parton showers, hadronization, and multiparton interactions. Event generators with only two outgoing high transverse momentum partons fail to describe the measurement, even when supplemented with next-to-leading-order QCD corrections and parton showers. Much better agreement is achieved when at least three outgoing partons are complemented through either next-to-leading-order predictions or parton showers. This observation emphasizes the need to improve predictions for multijet production.