Azimuthal angle decorrelations of jets widely separated in rapidity in pp collisions at sqrt{s} = 7 TeV

The azimuthal angle decorrelations of jets most forward and backward in rapidity (Mueller-Navelet jets) are measured with data collected in pp collisions with the CMS detector at the LHC at $\sqrt{s} = 7$ TeV. The azimutal angle distributions, average cosines of the difference in azimuthal angle between Mueller-Navelet jets, and ratios of the cosines are measured for jets with $p_{\mathrm{T}} > 35$ GeV and $\vert y \vert < 4.7$. The results are presented as a function of the rapidity separation $ \Delta y $ between jets, reaching a $ \Delta y $ up to 9.4 for the first time. The results are compared to predictions of various Monte-Carlo event generators and analytical predictions based on the DGLAP and BFKL parton evolution schemes. The measurements are also used to investigate effects of parton showering and multiparton interactions.